Sample records for weeds

  1. Weed ManagementWeed ManagementWeed ManagementWeed ManagementWeed Management Purdue Extension

    E-print Network

    WS-28-W Weed ManagementWeed ManagementWeed ManagementWeed ManagementWeed Management Purdue Educator Glenn R. W. Nice Purdue Extension Weed Professional Thomas Bauman Purdue Extension Weed Specialist Case R. Medlin Former Purdue Extension Weed Specialist In recent years, applications of herbi

  2. Weed ManagementWeed ManagementWeed ManagementWeed ManagementWeed Management Purdue Extension

    E-print Network

    Holland, Jeffrey

    Weed ManagementWeed ManagementWeed ManagementWeed ManagementWeed Management Purdue Extension WS-11-W Weed Management in Alfalfa Stands Dr. Case R. Medlin Assistant Professor of Weed Science Purdue University Steven D. Siegelin Adams County Extension Educator Purdue Extension Weed infestations can reduce

  3. WEED RESEARCH

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Weeds present in mint reduce oil yield and quality of mint oil. Several weed species have developed resistance to, or are poorly controlled by herbicides labeled for mint production. Low rates of mesotrione and sulfentrazone were tested for weed control and mint tolerance in field trials. Low rates...

  4. Alligator weed

    NSDL National Science Digital Library

    Robert H. Mohlenbrock (USDA-NRCS; )

    2006-11-12

    Alligator weed is a non-native species of plant in the United States that can damage waterways by clogging them and reducing water flow. Also, it grows in a way that reduces light penetration into the water. Alligator weed is being reduced by a few different insects that were released as biological control agents, such as the alligator weed flea beetle.

  5. Weed control

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Uncontrolled weeds in pepper can result in the total loss of the crop, or make harvest not economically feasible. Weed control is a major challenge in conventional and organic production systems. Agricultural weed control costs the U.S. economy more than the cost of insect and disease control comb...

  6. Flowers & Weeds.

    ERIC Educational Resources Information Center

    Flannery, Maura C.

    1996-01-01

    Describes the topics and teaching strategies employed in an Issues in Biology course. Discusses flowers, plant breeding, potatoes and tomatoes, the chocolate tree, weeds, Arabidopis, gene transfers, and plant genes/human genes. Contains 22 references. (JRH)

  7. Weed Biotypes Weed Management in Grain

    E-print Network

    Behmer, Spencer T.

    Weed Biotypes Weed Management in Grain Sorghum--New for 2012 Huskie Herbicide #12;2012 Sorghum, Extension weed scientist, Lubbock, (806) 746-6101, pdotray@ag.tamu.edu Central Texas Paul Baumann, Extension weed scientist, College Station, (9797) 845-3041, pbaumann@ag.tamu.edu #12;Huskie Herbicide for GS

  8. Green Weeding

    ERIC Educational Resources Information Center

    Penniman, Sarah; McColl, Lisa

    2008-01-01

    Gone are the days of tiptoeing to the dumpsters with boxes of weeded books in tow. Lots of libraries are now taking advantage of the many low-cost services and solutions that promise to help extend the lives of collection discards. Some of these options can be very profitable. Some create goodwill within the local community. Some may seem more…

  9. Modelling weed emergence patterns

    Microsoft Academic Search

    L. M. Vleeshouwers

    1997-01-01

    Anticipating weed pressure may be important in selecting and timing weed control measures in order to optimize their effectiveness, and thus reduce herbicide use. Therefore, a predictive model of the time of emergence and the numbers of seedling emerging (the weed emergence pattern) after soil cultivation may be a useful tool in integrated weed management. In this study, a simulation

  10. Weed Management -The Basics

    E-print Network

    Minnesota, University of

    Weed Management - The Basics Anthony Cortilet Minnesota Department of Agriculture Roger Becker University of Minnesota #12;Over-arching Weed Science Principles · Weed ecology and biology basic to all systems · Weed species cross over cropping boundaries · Perennial, biennial, or annual - disturbed

  11. Weed Identification Websites University of Florida Weed Science: http://weedext.ifas.ufl.edu/

    E-print Network

    Jawitz, James W.

    Weed Identification Websites · University of Florida Weed Science: http University Weed Science: http://www.weeds.iastate.edu/weedid/weedid.htm · Rutgers University New Jersey Weed Gallery: http://njaes.rutgers.edu/weeds · Virginia Tech Weed Identification Guide: http

  12. Weed Management Costs, Weed Best Management Practices, and The Roundup Ready Weed Management Program

    E-print Network

    Mitchell, Paul D.

    Weed Management Costs, Weed Best Management Practices, and The Roundup Ready® Weed Management-commercial purposes by any means, provide that this copyright notice appears on all such copies. #12;1 Weed Management Costs, Weed Best Management Practices, and The Roundup Ready® Weed Management Program T.M. Hurley

  13. Eradication of Major Weeds

    ERIC Educational Resources Information Center

    Indian Journal of Adult Education, 1975

    1975-01-01

    Strategies for weed control in cropped and non-cropped areas are presented together with an operational plan for implementing a program for weed control at the national level. The program includes training personnel and community education procedures. (EC)

  14. Introduction to Weeds and Herbicides.

    ERIC Educational Resources Information Center

    Hartwig, Nathan L.

    This agriculture extension service publication from Pennsylvania State University is an introduction to weed control and herbicide use. An initial discussion of the characteristics of weeds includes scientific naming, weed competition with crops, weed dispersal and dormancy, and conditions affecting weed seed germination. The main body of the…

  15. Introduction to Weeds and Herbicides

    E-print Network

    Kaye, Jason P.

    Introduction to Weeds and Herbicides #12;2 There are numerous definitions of a weed. Some common, weeds are plants whose undesirable qualities outweigh their good points, at least according to humans. Human activities create weed problems since no plant is a weed in nature. Though we may try

  16. Invasive Weed Outreach in Earl Creech

    E-print Network

    Nowak, Robert S.

    1 Invasive Weed Outreach in Nevada Earl Creech Extension Weed Specialist Cache Valley, Utah at Purdue What does the Extension Weed Specialist do? Control Nevada's weeds What does the Extension Weed Specialist do? Control Nevada's weeds Enforce weed control laws What does the Extension Weed Specialist do

  17. DEVELOPING WEED MANAGEMENT STRATEGIES THAT ADDRESS WEED SPECIES SHIFTS AND HERBICIDE RESISTANT WEEDS

    E-print Network

    Minnesota, University of

    DEVELOPING WEED MANAGEMENT STRATEGIES THAT ADDRESS WEED SPECIES SHIFTS AND HERBICIDE RESISTANT WEEDS Beverly R. Durgan and Jeffrey L. Gunsolus Extension Weed Scientists Department of Agronomy noticeable changes in the weed species that are difficult for them to control. In the past, problems

  18. WEED RESEARCH IN MINT

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Uncontrolled weeds in peppermint and spearmint reduce mint oil yield and quality. Several weed species have developed resistance to, or are poorly controlled by herbicides labeled for mint production. Flucarbazone, and propoxycarbazone applied to dormant native spearmint caused little or no crop inj...

  19. Mustard meal weed control

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Weed control in organic production systems can be a labor intensive and expensive process. Mustard meal (MM) is phytotoxic and a potential pre-emergent and preplant-incorporated organic herbicide for controlling germinating and emerging weed seedlings. Unfortunately, MM may also adversely impact s...

  20. WeedControl WEED CONTROL IN FLUE-CUREDTOBACCO

    E-print Network

    Liskiewicz, Maciej

    37 WeedControl WEED CONTROL IN FLUE-CUREDTOBACCO Charles S. Johnson, Extension Plant Pathologist, Tobacco Good weed control uses crop rotation, early root and stalk destruction, cultivation-the-top at transplanting (OT) will reduce reliance on the first cultivation for early-season weed control. The number

  1. Weeds on the Web

    NSDL National Science Digital Library

    The Wildland Invasive Species Program of The Nature Conservancy (TNC) hosts this interesting and light-hearted page on the invasive plants currently threatening the biodiversity of wild lands in the US. Appropriate for undergraduates, educators will find much here on weeds (what they are, which ones are worst), weed control methods, and suggestions for including action in lesson plans. For starters, click on any state in the US map to find out about the worst invasive plants in that state. Those seeking detailed information should consult the Element Stewardship Abstracts, which describe over 100 species in terms of Scientific and Common Name, Description of Characteristics, Biology/ Ecology, Global Range, Stewardship Profile, Threats Posed by this Species, Biological Control, Research Needs, and more. Also at the site are lists of effective weed tools, weeds in the news, and links to weed-related events.

  2. AQUATIC WEED CONTROL SPRING 2013

    E-print Network

    Watson, Craig A.

    PLS 4613 AQUATIC WEED CONTROL SPRING 2013 CREDITS: 3.0 DESCRIPTION: Identification of Florida's aquatic weed problems and methods of chemical, biological, mechanical and physical weed control. Specific, insect biocontrol, grass carp, and current laws regulating aquatic weed control. INSTRUCTOR: William T

  3. SUGGESTIONS FOR WEED CONTROL IN

    E-print Network

    Mukhtar, Saqib

    B-5038 10-98 SUGGESTIONS FOR WEED CONTROL IN PASTURES AND FORAGES Texas Agricultural Extension;4 Suggestions for Weed Control in Pastures and Forages Dr. Paul A. Baumann, Extension Weed Specialist Dr. David as a guide for controlling weeds in pasture and forages. Labeled rates and restrictions change constantly

  4. Tolerance of Crops and Susceptibility of Weeds

    E-print Network

    Guide to Tolerance of Crops and Susceptibility of Weeds to Herbicides Bernard Zandstra and Michael . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 List of Weeds . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 Weed Control Ratings for each Herbicide

  5. Modelling weed emergence patterns in arable weeds

    Microsoft Academic Search

    L. M. Vleeshouwers; M. J. Kropff

    2000-01-01

    A model was developed to simulate weed emergence patterns after soil cultivation. In the model, the consecutive processes of dormancy release, germination and pre-emergence growth were modelled in separate modules. Input variables of the model were: date of soil cultivation, soil temperature and soil penetration resistance. Output variables of the model were: seedling density and timing of seedling emergence. The

  6. Genomics for Weed Science

    PubMed Central

    Horvath, David

    2010-01-01

    Numerous genomic-based studies have provided insight to the physiological and evolutionary processes involved in developmental and environmental processes of model plants such as arabidopsis and rice. However, far fewer efforts have been attempted to use genomic resources to study physiological and evolutionary processes of weedy plants. Genomics-based tools such as extensive EST databases and microarrays have been developed for a limited number of weedy species, although application of information and resources developed for model plants and crops are possible and have been exploited. These tools have just begun to provide insights into the response of these weeds to herbivore and pathogen attack, survival of extreme environmental conditions, and interaction with crops. The potential of these tools to illuminate mechanisms controlling the traits that allow weeds to invade novel habitats, survive extreme environments, and that make weeds difficult to eradicate have potential for both improving crops and developing novel methods to control weeds. PMID:20808523

  7. Controlling Weeds in Nursery and Landscape Plantings

    E-print Network

    Guiltinan, Mark

    Controlling Weeds in Nursery and Landscape Plantings #12;2 To the user of this publication ..................................................................... 3 Weed Control Program .................................................... 3 Weed Control Methods....................................................................23 Fumigants .........................................................................27 Weed Control

  8. Grass and weed killer poisoning

    MedlinePLUS

    ... by swallowing weed killers containing a chemical called glyphosate. This is for information only and not for ... Glyphosate ... Glyphosate is found in various weed killers, including the brands listed below: Roundup Bronco Glifonox Kleen-up ...

  9. Assistant Professor Agronomy (Weed Science)

    E-print Network

    Watson, Craig A.

    Ramon Leon Assistant Professor Agronomy (Weed Science) Research Focus Dr. Leon has a 60% research research and extension program is to develop and implement integrated approaches for weed management that promote crop health and growers' profitability in row crops and turf. His research emphasizes weed

  10. WeedControl Recommendations

    E-print Network

    Mukhtar, Saqib

    Figure 1.Feekes scale for the growth and development of cereals ........7 Table 1.Preplant herbicides.Herbicide restrictions and mode of action .........................16 Table 7.Herbicide efficacy for grasses plowing perennial weeds, take care to prevent the transport and spread of plant parts to other areas

  11. Weed-It: a new selective weed control system

    NASA Astrophysics Data System (ADS)

    Visser, R.; Timmermans, A. J. M.

    1996-12-01

    An automatic selective herbicide spraying system for weed control has been developed. When driving at 10 km/h, the system can spray weeds with a spatial resolution of about 10 cm2. Weed plants as small as 10 mm2 can be detected. Thus, weed plants are sprayed upon, whereas parts of the treated surface where no weed is present are left free of herbicide. In comparison to full-field treatments, a considerable amount of herbicide is saved in this way, with positive effects on treatment cost and environmental friendliness. The system consists of a series of parallel opto-electronic weed sensors scanning the surface, velocity sensors, an industrial PC for data processing, and herbicide sprayers mounted behind the weed sensors. Unlike in other selective spraying systems, the weed sensors do not employ the reflectance properties of weed, but the fluorescence properties. Although the sensor have been originally developed for weed detection, modification of the optics makes them suitable for the detection of a wide variety of objects and chemicals in agriculture and industry.

  12. Why herbicides fail Extension Weed Specialist

    E-print Network

    Watson, Craig A.

    Why herbicides fail J. Ferrell Extension Weed Specialist and Greg MacDonald Weed Scientist #12 problems, or forgetting to add the herbicide to the sprayer. #12;Proper Weed ID #12;Johnsongrass Guinea grass #12;Don't assume your herbicide will kill every weed · Milestone VM controls many weeds

  13. Seasonal Weed Control for Northeast Florida

    E-print Network

    Jawitz, James W.

    1 Seasonal Weed Control for Northeast Florida #12;2 Introduction Weed control is a constant battle things you can do to reduce the economic impact of weeds. A healthy pasture has fewer weed problems. Soil to maintain a weed free pasture. Always use certi- fied seed to establish pastures and hay fields. Clean

  14. Mapping Weed Presence in Dryland Crops

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Weed maps are useful to monitor the effectiveness of weed control, detect new invasions, plan preventative weed management for following crops and use site-specific weed management to reduce herbicide use. Sophisticated methods to map weed populations are being developed with slow progress. We devel...

  15. EXOTIC AND INVASIVE HERBACEOUS RANGE WEEDS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Resource managers are often discouraged when it comes to the identification of herbaceous rangeland weeds, terminology associated with these weeds, control of these weeds, and the succession of these weeds. The terminology often used in describing herbaceous rangeland weeds (i. e. invasive) often m...

  16. 296 Weed Science 53, MayJune 2005 Weed Science, 53:296306. 2005

    E-print Network

    Sims, Gerald K.

    296 · Weed Science 53, May­June 2005 Weed Science, 53:296­306. 2005 Weed seedbank and community of Agriculture­Agricultural Research Services, Invasive Weeds Management Unit, N-319 Turner Hall, 1102 South-term effect of agricultural management systems on weed communities will aid in developing sustainable weed

  17. 558 Weed Science 54, MayJune 2006 Weed Science, 54:558565. 2006

    E-print Network

    Sims, Gerald K.

    558 · Weed Science 54, May­June 2006 Weed Science, 54:558­565. 2006 Symposium When does it make sense to target the weed seed bank? Adam S. Davis Corresponding author: USDA-ARS Invasive Weeds Management Unit, Urbana, IL 61801; asdavis1@uiuc.edu Weed seeds initiate most weed invasions of arable fields

  18. PRINCIPLES OF WEED SCIENCE -PLS 4601c INTEGRATED WEED MANAGEMENT PLS 5632c

    E-print Network

    Watson, Craig A.

    1 PRINCIPLES OF WEED SCIENCE - PLS 4601c INTEGRATED WEED MANAGEMENT ­ PLS 5632c Department Description: An introduction to the principles of weed science. Lecture topics will include: weed biology and ecology, an introduction to weed management techniques and methodologies, factors affecting weed control

  19. Weed Management in Alfalfa Stands Dr. Case R. Medlin

    E-print Network

    Weed Management in Alfalfa Stands Dr. Case R. Medlin Assistant Professor of Weed Science Purdue Weed ManagementWeed ManagementWeed ManagementWeed ManagementWeed Management Purdue Extension WS-11-W Weed infestations can reduce the yield, quality, and longevity of alfalfa stands. Low soil p

  20. 7 CFR 201.15 - Weed seeds.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 3 2011-01-01 2011-01-01 false Weed seeds. 201.15 Section 201.15 Agriculture...REGULATIONS Labeling Agricultural Seeds § 201.15 Weed seeds. The percentage of weed seeds shall include seeds of plants...

  1. 7 CFR 201.15 - Weed seeds.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 3 2013-01-01 2013-01-01 false Weed seeds. 201.15 Section 201.15 Agriculture...REGULATIONS Labeling Agricultural Seeds § 201.15 Weed seeds. The percentage of weed seeds shall include seeds of plants...

  2. 7 CFR 201.15 - Weed seeds.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 3 2010-01-01 2010-01-01 false Weed seeds. 201.15 Section 201.15 Agriculture...REGULATIONS Labeling Agricultural Seeds § 201.15 Weed seeds. The percentage of weed seeds shall include seeds of plants...

  3. 7 CFR 201.15 - Weed seeds.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 3 2012-01-01 2012-01-01 false Weed seeds. 201.15 Section 201.15 Agriculture...REGULATIONS Labeling Agricultural Seeds § 201.15 Weed seeds. The percentage of weed seeds shall include seeds of plants...

  4. 7 CFR 201.15 - Weed seeds.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 3 2014-01-01 2014-01-01 false Weed seeds. 201.15 Section 201.15 Agriculture...REGULATIONS Labeling Agricultural Seeds § 201.15 Weed seeds. The percentage of weed seeds shall include seeds of plants...

  5. Soil, Weeds, and Computers

    NSDL National Science Digital Library

    Nate McClennen

    2004-05-01

    After a 2001 wildfire in the state of Wyoming, scientists were interested in learning what hydrophobic layers existed in the heavily burned areas and at what depth. In a collaborative, inquiry-based project, high school students collected soil chemistry data that helped biologists learn more about controlling noxious weed invasion. As a result of this collaboration, students became part of the process of science and members of the scientific community.

  6. Weed flora and weed management of field peas in Finland

    Microsoft Academic Search

    Jukka Salonen; Terho Hyvönen; Heikki Jalli

    2005-01-01

    The composition of the weed flora of dry pea (Pisum sativum L.) fields and cropping practices were inves- tigated in southwestern Finland. Surveys were done in 2002-2003 in 119 conventionally cropped fields and 64 fields under organic cropping. Herbicides were applied to 92% of conventionally cropped fields where they provided relatively good control but were costly. Weeds were controlled mechanically

  7. Invasive Weed Management Is Site-Specific Weed Management.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Site-specific weed management in crops and invasive weed management in natural lands and rangelands appear to be unrelated research areas but there are many connections in the research problems, approaches and solutions. An obvious link is technology. The technology of precision agriculture - GPS, ...

  8. Weed Identification Field Training Demonstrations.

    ERIC Educational Resources Information Center

    Murdock, Edward C.; And Others

    1986-01-01

    Reviews efforts undertaken in weed identification field training sessions for agriprofessionals in South Carolina. Data over a four year period (1980-1983) revealed that participants showed significant improvement in their ability to identify weeds. Reaffirms the value of the field demonstration technique. (ML)

  9. Davis et al.: Weed seed mortality 291 Weed Science, 54:291297. 2006

    E-print Network

    Sims, Gerald K.

    Davis et al.: Weed seed mortality · 291 Weed Science, 54:291­297. 2006 Weed seed mortality in soils Sciences, Michigan State University, East Lansing, MI 48824. Current address: USDA-ARS Invasive Weeds the devel- opment of soil microbial communities that accelerate weed seed mortality. We ex- amined soil

  10. 62 Weed Science 53, JanuaryFebruary 2005 Weed Science, 53:6268. 2005

    E-print Network

    Sims, Gerald K.

    62 · Weed Science 53, January­February 2005 Weed Science, 53:62­68. 2005 Duration of volunteer States Department of Agriculture­Agricultural Research Service, Invasive Weed Management Research research with annual weed species indicates that critical timing of weed removal begins primarily after

  11. 248 Weed Science 50, MarchApril 2002 Weed Science, 50:248260. 2002

    E-print Network

    Bradford, Kent

    248 · Weed Science 50, March­April 2002 Weed Science, 50:248­260. 2002 Applications of hydrothermal@ucdavis.edu Knowledge and prediction of seasonal weed seedling emergence patterns is useful in weed management programs and nutrients to support plant growth. Seed dormancy is a characteristic feature of many weed species, allowing

  12. Microbial weed control and microbial herbicides

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Microbes can be used in weed control. There have been many investigations of potential products for weed management. Some have been successful at suppressing weeds in the field and a select few are marketed products that now reduce weed infestations. Further studies are needed to continue to searc...

  13. 7 CFR 201.50 - Weed seed.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ...2011-01-01 2011-01-01 false Weed seed. 201.50 Section 201.50 ...Administration of the Act § 201.50 Weed seed. Seeds (including bulblets or tubers) of plants shall be considered weed seeds when recognized as weed...

  14. Weeding the School Library Media Collection.

    ERIC Educational Resources Information Center

    School Library Media Quarterly, 1984

    1984-01-01

    This document prepared by Calgary Board of Education, Calgary, Alberta, Canada, discusses a systematic approach to strengthening the library media collection. A statement of principle, what to weed, specific guides to weeding (by Dewey Decimal classification and type of material), what not to weed, procedures, and weeding follow-up are…

  15. 7 CFR 201.50 - Weed seed.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ...2013-01-01 2013-01-01 false Weed seed. 201.50 Section 201.50 ...Administration of the Act § 201.50 Weed seed. Seeds (including bulblets or tubers) of plants shall be considered weed seeds when recognized as weed...

  16. 7 CFR 201.50 - Weed seed.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ...2014-01-01 2014-01-01 false Weed seed. 201.50 Section 201.50 ...Administration of the Act § 201.50 Weed seed. Seeds (including bulblets or tubers) of plants shall be considered weed seeds when recognized as weed...

  17. Home Orchard Weed Control By Paul Vossen

    E-print Network

    California at Davis, University of

    Home Orchard Weed Control By Paul Vossen As I visit home orchardist's back yard trees one of the most frequent problems I see is excessive weed competition. I see many trees that do not have adequate weed control to a point where the weeds have hindered the growth of the young trees. We have extensive

  18. 7 CFR 201.50 - Weed seed.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ...2012-01-01 2012-01-01 false Weed seed. 201.50 Section 201.50 ...Administration of the Act § 201.50 Weed seed. Seeds (including bulblets or tubers) of plants shall be considered weed seeds when recognized as weed...

  19. Weed Control Recommendations in Wheat 

    E-print Network

    Morgan, Gaylon; Baumann, Paul A.; Baughman, Todd; Bean, Brent W.

    2008-06-05

    rocket, wild radish. Annual weeds: small. Perennial weeds: at bud stage but before wheat boot stage. After 4-leaf stage up to boot stage; high rate after tiller to early boot stage. Late-season application for control of perennial weeds must.... Feekes scale for the growth and development of cereals 1 2 3 4 5 6 7 8 9 10 10.1 10.5 11 one tillering tillers leaf leaf first node second last leaf ligule in head flowering shoot begins formed sheaths sheaths of stem node just of last ?boot? visible...

  20. Weed Control in Texas Pastures. 

    E-print Network

    Long, John A.; Trew, E. M.

    1958-01-01

    .................................................................................. Chemicals Used 7 ...................................................... t Controls for Specific Situations 8 ............................... i Common Cultivated Pasture Weeds in Texas ......................................................... 11... and nozzles that permit coarse sprays to prevent fine, misty spray. 8. Keep the spray boom or nozzle as close to the ground as possible and still obtain goo, coverage. 9. Do not apply 2,4-D to weeds growing slowly because of drcuuth or that are approachi...

  1. 2010 Pulse Weed Control Studies Brian Jenks and Ed Davis

    E-print Network

    Maxwell, Bruce D.

    1 2010 Pulse Weed Control Studies Brian Jenks and Ed Davis NDSU and MSU Clearfield lentil weed......................................................... 15 Effect of Sharpen and Aim on weed control with Glyphosate............................................ 16 Effect of Sharpen and Aim on weed control with Glyphosate

  2. Molecular biology of weed control.

    PubMed

    Gressel, J

    2000-01-01

    The vast commercial effort to utilize chemical and molecular tools to solve weed control problems has had a major impact on the basic biological sciences as well as benefits to agriculture, and the first generation of transgenic products has been successful, while somewhat crude. More sophisticated products are envisaged and expected. Biotechnologically-derived herbicide-resistant crops have been a considerable benefit, yet in some cases there is a risk that the same useful transgenes may introgress into related weeds, specifically the weeds that are hardest to control without such transgenic crops. Biotechnology can also be used to mitigate the risks. Molecular tools should be considered for weed control without the use of, or with less chemicals, whether by enhancing crop competitiveness with weeds for light, nutrients and water, or via allelochemicals. Biocontrol agents may become more effective as well as more safe when rendered hypervirulent yet non-spreading by biotechnology. There might be ways to disperse deleterious transposons throughout weed populations, obviating the need to modify the crops. PMID:11131013

  3. Cultural practices in cotton (Gossypium hirsutum) affect weed seed production

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Billions of dollars are lost annually due to weeds or weed control, but weeds persist. Successful weed management systems must reduce weed populations. The objectives of this research were to 1) determine if cotton row spacing has an impact on weed growth and seed production and 2) evaluate the infl...

  4. Using Stochastic Effciency Analysis To Factor Distribution Of Weed Escapes Into Weed Management Decisions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Weeds in patches may be more easily managed than the same number of weeds spread throughout the field. We explored choosing weed management strategies based on both net return and the distribution of weed escapes within a field. Expected net returns with several different postemergence herbicides of...

  5. 902 Weed Science 53, NovemberDecember 2005 Weed Science, 53:902908. 2005

    E-print Network

    Landis, Doug

    902 · Weed Science 53, November­December 2005 Weed Science, 53:902­908. 2005 Symposium Manipulating habitats dominated by a few plant species where pesticides play a major role in managing weed and insect by manipulating plant species and communities to benefit natural enemies of insects and weeds. Such efforts aim

  6. 94 Weed Science 54, JanuaryFebruary 2006 Weed Science, 54:9499. 2006

    E-print Network

    Sims, Gerald K.

    94 · Weed Science 54, January­February 2006 Weed Science, 54:94­99. 2006 Volunteer potato­Agricultural Research Service, Invasive Weed Management Research, University of Illinois, 1102 S. Goodwin Ave., Urbana Research Service, Vegetable and Forage Crops Research, Prosser, WA 99350 Weed management systems in carrot

  7. 838 Weed Science 54, SeptemberOctober 2006 Weed Science, 54:838846. 2006

    E-print Network

    Zhang, Hao

    838 · Weed Science 54, September­October 2006 Weed Science, 54:838­846. 2006 Modeling site the landscape and may facilitate better timing of weed control where residue is present. Emergence of wild oat to improving prediction of weed seedling emergence. Nomenclature: Wild oat, Avena fatua L., AVEFA; winter wheat

  8. 930 Weed Science 51, NovemberDecember 2003 Weed Science, 51:930939. 2003

    E-print Network

    Sims, Gerald K.

    930 · Weed Science 51, November­December 2003 Weed Science, 51:930­939. 2003 Cropping system Department of Agronomy, Iowa State University, Ames, IA 50011 Cropping system characteristics affect weed management by altering key demograph- ic rates of weeds, including recruitment, seedling survival, fecundity

  9. 928 Weed Science 54, SeptemberOctober 2006 Weed Science, 54:928933. 2006

    E-print Network

    Sims, Gerald K.

    928 · Weed Science 54, September­October 2006 Weed Science, 54:928­933. 2006 Planting date influences critical period of weed control in sweet corn Martin M. Williams II Corresponding author. U.S. Department of Agriculture--Agricultural Research Service, Invasive Weed Management Research, University

  10. www.btny.purdue.edu/weedscience/ Noxious and Invasive Weeds and The Weed

    E-print Network

    www.btny.purdue.edu/weedscience/ Noxious and Invasive Weeds and The Weed Laws in Indiana Many of us have heard the terms `noxious' and `invasive' weeds or plants. However, I would suspect weeds in these groups. If you would like to read the Indiana Code yourself or you have trouble sleeping

  11. 368 Weed Science 53, MayJune 2005 Weed Science, 53:368. 2005

    E-print Network

    Sims, Gerald K.

    368 · Weed Science 53, May­June 2005 Weed Science, 53:368. 2005 Symposium Introduction to the symposium Beyond thresholds: applying multiple tactics within integrated weed management systems More than specialists, integrated weed management (IWM) remains elusive in practice. Most definitions of IWM have two

  12. Weed Emergence Patterns and the Effect of Time of Weed Removal, with

    E-print Network

    Minnesota, University of

    Weed Emergence Patterns and the Effect of Time of Weed Removal, with Glyphosate, on Corn and Soybean Yield · In 2004 - 2006, research compared weed removal at 5 glyphosate timings (1", 3", 5", 7" and 9" weed heights), with and without a ½-rate of a PRE herbicide, on crop yield and economic returns

  13. 860 Weed Science 53, NovemberDecember 2005 Weed Science, 53:860868. 2005

    E-print Network

    Sims, Gerald K.

    860 · Weed Science 53, November­December 2005 Weed Science, 53:860­868. 2005 Environmental factors affecting seed persistence of annual weeds across the U.S. corn belt Adam S. Davis1 John Cardina2 Frank State University, East Lansing, MI 48824; Current address: USDA-ARS Invasive Weed Management Unit

  14. Sorghum Allelopathy for Weed Management in Wheat

    Microsoft Academic Search

    Zahid A. Cheema; Abdul Khaliq; Muhammad Farooq

    Weeds cause substantial decline in agricultural production. To overcome weed infestation modern agricultural practices adopted\\u000a heavy use of a large variety of herbicides. With rising human health and ecological concerns about the adverse effects of\\u000a indiscriminate use of farm chemicals research on alternative weed management methods is underway worldwide. Exploitation of\\u000a allelopathic potential of different crop\\/plant species for weed management

  15. Patchy weed distribution and site-specific weed control in winter cereals

    Microsoft Academic Search

    Henning Nordmeyer

    2006-01-01

    Site-specific weed control in winter cereals was performed on the same fields every year over a 5-year period (1999–2003). The most common weeds (Apera spica-venti, Galium aparine, Veronica hederifolia, Viola arvensis) were counted by species, at grid points which were georeferenced and the data were analysed spatially. For weed control, weeds were grouped into three classes: grass, broad-leaved weeds (without

  16. Control of Summer Annual Grass Weeds

    E-print Network

    Kaye, Jason P.

    Control of Summer Annual Grass Weeds in Turfgrasses Summer annual grasses continue to be pervasive weed problems in many turfgrass areas throughout Pennsylva nia. The most common summer annual grasses.), and barnyard grass (Echi- nochloa crusgalli). Satisfactory control of these weeds can be obtained by cultural

  17. Extension/Research Professor of Weed Science

    E-print Network

    Watson, Craig A.

    John Byrd Extension/Research Professor of Weed Science Box 9555 Mississippi State, MS 39762 662 excellent weed exterminators. Kerosene or waste oil from garages..." · "...oils of this kind should feet would seem a fair estimate." #12;Sulfuric Acid Spray: A practical means for the control of weeds

  18. Weed control efficacy with Racer (ammonium nonanoate)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Weed control is a major challenge in conventional and organic production systems. Agricultural weed control costs the U.S. economy more than the cost of insect and disease control combined. Organic vegetable producers have many challenges since their weed control tools are mostly limited to cultur...

  19. Weed control options for transplanted onions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    As interest in sweet onion production has grown in Oklahoma and Arkansas, so has the realization that uncontrolled weeds can result in a total loss of marketable onion production. Although mechanical weed control can successfully control weeds between rows, producers need reliable methods for contro...

  20. Using weeds to fight wastes

    SciTech Connect

    NONE

    1992-10-01

    Researchers at Los Alamos National Laboratory and New Mexico State University have discovered that jimson weed and wild tomato plants can remove the toxic wastes in wastewater associated with the production of trinitrotoluene (TNT). According to Wolfgang F. Mueller of New Mexico State, tissue-cultured cells of jimson weed rapidly absorb and break down toxic and carcinogenic elements in {open_quotes}pink water,{close_quotes} a by-product of the manufacture of TNT. Mueller and his colleagues have found similar results with the wild tomato plant.

  1. Weed Busters: Sprayer Calibration Guide 

    E-print Network

    McGinty, Allan; Hanselka, C. Wayne; Lyons, Robert K.; Hart, Charles R.; Cadenhead, J. F.

    2005-03-07

    to rangeland. ?Broadcast sprays can drift, especially when boom- less nozzles are used. ?Read and follow the herbicide label directions. L-5465 1/05 Sprayer Calibration Guide Safe and effective four-step method to calibrate herbicide sprays Weed Treatment... is important. If you apply too much herbicide, costs can become excessive; you may be in violation of the label; and you might cause environmental dam- age. If you apply too little herbicide, the weeds may not be controlled adequately. Many sprayer calibration...

  2. RHIZOBACTERIA INHIBITORY TO GRASS WEEDS.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Soil bacteria have been discovered that can be used as biological agents to suppress downy brome and certain other grass weeds in small grains. Our research on these organisms has shown that their use has the potential to reduce tillage, agrochemical usage and related ground and surface water conta...

  3. Genomics and Weeds: A Synthesis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Genomics can be used to solve many problems associated with the management of weeds. New target sites for herbicides have been discovered through functional genomic approaches to determine gene function. Modes of action of herbicides can be clarified or discovered by transcriptome analysis. Under...

  4. CLASSICAL BIOLOGICAL CONTROL OF WEEDS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Classical biological control of weeds is an important tool for managing invasive alien plants that have become too widespread to control by conventional methods. It involves the discovery and release of naturally occurring species of natural enemies (insects, mites or pathogens) to control a pest (...

  5. HOME GROUNDS & ANIMALS 2014 5-8 Lawn: Weeds

    E-print Network

    Liskiewicz, Maciej

    HOME GROUNDS & ANIMALS 2014 5-8 Lawn: Weeds Weeds Shawn D. Askew, Associate Professor, Virginia Tech Overview The first step in any lawn weed management program is to identify the problem. What grass kills seedling weeds and prevents large weed stands, which tend to decrease lawn aesthetics

  6. Increasing Crop Competitiveness to Weeds Through Crop Breeding

    Microsoft Academic Search

    Todd A. Pester; Orvin C. Burnside; James H. Orf

    1999-01-01

    Increasing the ability of crops to compete against weeds, through either enhancing crop tolerance or crop interference to weeds, provides an attractive addition to current weed control practices and could be an integral component of weed management systems. Research has shown that considerable variability exists among crop culti-vars with respect to their ability to compete with weeds. Despite this evidence,

  7. The future for weed control and technology.

    PubMed

    Shaner, Dale L; Beckie, Hugh J

    2014-09-01

    This review is both a retrospective (what have we missed?) and prospective (where are we going?) examination of weed control and technology, particularly as it applies to herbicide-resistant weed management (RWM). Major obstacles to RWM are discussed, including lack of diversity in weed management, unwillingness of many weed researchers to conduct real integrated weed management research or growers to accept recommendations, influence or role of agrichemical marketing and governmental policy and lack of multidisciplinary research. We then look ahead to new technologies that are needed for future weed control in general and RWM in particular, in areas such as non-chemical and chemical weed management, novel herbicides, site-specific weed management, drones for monitoring large areas, wider application of 'omics' and simulation model development. Finally, we discuss implementation strategies for integrated weed management to achieve RWM, development of RWM for developing countries, a new classification of herbicides based on mode of metabolism to facilitate greater stewardship and greater global exchange of information to focus efforts on areas that maximize progress in weed control and RWM. There is little doubt that new or emerging technologies will provide novel tools for RMW in the future, but will they arrive in time? PMID:24339388

  8. Review: The phenomenon of crop-weed competition; a problem or a key for sustainable weed management?

    Microsoft Academic Search

    Aspasia P. Efthimiadou; Anestis C. Karkanis; Dimitrios J. Bilalis; Panagiotis Efthimiadis

    2009-01-01

    Herbicide resistance in weeds is rapidly expanding phenomenon around the world resulting in higher costs of production and greater weed impact. With current pressures to reduce herbicide usage but maintain cost-effective weed control, the innate ability of crops or cultivars to suppress weed growth has become increasingly important. The increasing appearance of herbicide-resistant weeds in the fields may force breeders

  9. Revised 1/09 PLANT / WEED IDENTIFICATION AND CONTROL

    E-print Network

    Duchowski, Andrew T.

    Revised 1/09 PLANT / WEED IDENTIFICATION AND CONTROL Items with * must be completed for control ____________________ Date submitted ___________________ Mail report (No email) PLANT OR WEED INFORMATION. Items with * must ______________________________ rate ____________________________when__________________________ none used unknown 6. If weed

  10. Weed Identification: Using Plant Structures as a Key 

    E-print Network

    Baumann, Paul A.

    2002-04-15

    Weed identification is necessary to the success of any weed control program. Frequently, simple plant keys or "picture book identification guides are used to identify weeds. This handbook, which identifies and labels plant structures, can help one...

  11. Weed Identification: Using Plant Structures as a Key (Spanish) 

    E-print Network

    Baumann, Paul A.

    1999-08-30

    Weed identification is necessary to the success of any weed control program. Frequently, simple plant keys or "picture book identification guides are used to identify weeds. This handbook, which identifies and labels plant structures, is intended...

  12. Factors which facilitate waste water treatment by aquatic weeds – the mechanism of the weeds’ purifying action

    Microsoft Academic Search

    Tasneem Abbasi; S. A. Abbasi

    2010-01-01

    Aquatic weeds such as water hyacinth, salvinia, pistia, and lemna have proved to be powerful bioagents which significantly purify wastewater lying under them. Even the performance of conventional oxidation ponds can be greatly enhanced by the simple expedient of introducing one of these aquatic weeds. Weeds absorb certain pollutants. But the contribution of absorption to the overall treatment is only

  13. UC Davis Weed Science 1 Brad Hanson, Tom Lanini, and Lynn Sosnoskie, UC Davis Weed Science

    E-print Network

    Hanson, Brad

    2/21/2012 2012 CWSS UC Davis Weed Science 1 Brad Hanson, Tom Lanini, and Lynn Sosnoskie, UC Davis Weed Science bhanson@ucdavis.edu Cuttings first brought to North America from France in 1856 floors are managed for a number of reasons Facilitate crop production and harvest practices Weed

  14. WEED COMMUNITY COMPOSTION IN RESPONSE TO ORGANIC AND CONVENTIONAL WEED CONTROL PRACTICES IN A CALIFORNIA VINEYARD

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Integrated weed management (IWM) employs multiple tactics to control weed infestations, and can be useful in reducing problematic weeds. IWM in California vineyards typically involves the integration of post-emergence herbicides and pre-emergence herbicides, with less emphasis on incorporation of no...

  15. N-Q Weed killer

    NSDL National Science Digital Library

    This is a task from the Illustrative Mathematics website that is one part of a complete illustration of the standard to which it is aligned. Each task has at least one solution and some commentary that addresses important asects of the task and its potential use. Here are the first few lines of the commentary for this task: A liquid weed-killer comes in four different bottles, all with the same active ingredient. The accompanying table gives information about the concentra...

  16. Dominant species of dicot-weeds and weed biodiversity in spring barley in Latvia.

    PubMed

    Vanaga, I; Mintale, Z; Smirnova, O

    2010-01-01

    The composition of weed species in spring barley and weed biodiversity was evaluated in experiments in different growing seasons and with different previous crops. The aim of the experiments was to evaluate the composition of weed species in spring barley during a four year period in weather conditions of different growing seasons and with different previous crop as well as to assess the biodiversity in the experiments where the different groups of herbicides were applied. Over years and previous crops, the dicotyledonous weed community was dominated by Chenopodium album, followed by Viola arvensis. The herbicides from different groups had significant influences on the biodiversity of weeds. PMID:21542476

  17. PRECISION FARMING TECHNIQUES FOR WEED MANAGEMENT

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Preliminary studies were conducted to investigate methods of geo- referencing weed locations in fields for site-specific application of herbicides. Ground-based and aerial methods were examined. Ground-based methods included scouting fields with a backpack GPS and marking areas where weeds were pr...

  18. Control of grassy weeds in annual canarygrass

    Microsoft Academic Search

    M. Cogliatti; V. F. Juan; F. Bongiorno; H. Dalla Valle; W. J. Rogers

    2011-01-01

    There are currently no herbicides registered in Argentina for the selective control of grassy weeds in annual canarygrass (Phalaris canariensis L.). The principal grassy weeds are darnel ryegrass (Lolium temulentum L.) and wild oats (Avena fatua L.), which cause grain yield and quality losses. The potential of diclofop-methyl and clordinafop-propargyl for their control was assessed through greenhouse and field trials,

  19. WEED MANAGEMENT IN CONSERVATION CROP PRODUCTION SYSTEMS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Information on weed management in conservation crop production systems is needed as adoption of practices such as reduced tillage and cover crops become more widespread. This review summarizes recent research on weed management aspects in these systems. Changes in soil environment and patterns of t...

  20. Molecular biology approaches to weed management

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Global climate change appears to be favorable for invasive weed development and spread because invasive species in general are proficient at succeeding in new environments. To worsen matters, herbicide-resistant weeds have become a severe threat in modern agricultural systems due to the extensive us...

  1. Weeding the Library Media Center Collections.

    ERIC Educational Resources Information Center

    Buckingham, Betty Jo

    These guidelines for weeding library media collections are addressed to elementary and secondary school library media centers and to community college and vocational school library resource centers in Iowa. The publication includes some philosophy about weeding, and specific guidelines are summarized in bold-faced type for ease of use. The…

  2. Yield advances in peanut - weed control effects

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Improvements in weed management are a contributing factor to advancements in peanut yield. Widespread use of vacuum planters and increased acceptance of narrow row patterns enhance weed control by lessening bareground caused by skips and promoting quick canopy closure. Cultivation was traditionall...

  3. Post-directed weed control in squash

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Organic squash (Cucurbita pepo L.) producers need appropriate herbicides that can effectively provide season- long weed control. Research was conducted in southeast Oklahoma (Atoka County, Lane, OK) to determine the impact of a potential organic herbicide on weed control efficacy, crop injury, and ...

  4. Weed interference in soybean (Glycine max)

    Microsoft Academic Search

    Irawati Chaniago; Acram Taji; Robin Jessop

    The interactions of 3 cultivars of soybean (Banjalong, Melrose and Valiant) with Powell's amaranth (Amaranthus powellii), paspalum (Paspalum dilatatum) and nutgrass (Cyperus rotundus) was studied using different systems. A glasshouse experiment was conducted to determine soybean response towards weeds at different density levels. Hydroponic culture was included to study the allelopathic effects of the weed extracts on soybean root growth

  5. Suggestions For Weed Control In Cotton

    E-print Network

    Baumann, Paul A.; Lemon, Robert G.

    2007-07-03

    - nearsonate) Helena and others 30?40 gal water with surfactant. 5?10 gal aerial. Before planting. Apply once to emerged weeds and grass before planting. Cotton may be planted immediately. Emerged annual broad- leaf weeds and grasses and topkill...

  6. Weed competition and dry bean yield components

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Weed competition can significantly reduce dry bean (Phaseolus vulgaris L.) yields and therefore the profitability for the producer. Depending on the dry bean variety produced, the yield components may be affected differently by the stress produced by weed competition. This research was conducted to ...

  7. Integrating management of soil nitrogen and weeds

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Crop-weed interference often depends on soil nitrogen (N) supply and the N mineralization potential of the soil. Knowledge of these soil properties combined with an understanding of weed-crop competition dynamics in response to soil nutrient levels can be used to optimize N fertilizer rates to shift...

  8. ECOLOGICAL WEED MANAGEMENT FOR ORGANIC FARMING SYSTEMS

    Microsoft Academic Search

    Derek M. Law

    2006-01-01

    Two field studies examining direct ecological weed control practices were conducted in Lexington, Kentucky. The first evaluated weed control efficacy and influence on yields of several mulches in two organically-managed bell pepper (Capsicum annum) production systems for two years. Peppers were planted in double rows in flat, bare ground or on black polyethylene-covered raised beds with drip irrigation, and four

  9. Integrating Residual Herbicides into Corn and Soybean Weed Management

    E-print Network

    Minnesota, University of

    Integrating Residual Herbicides into Corn and Soybean Weed Management Plans Jeffrey L. Gunsolus gunso001@umn.edu #12;Harvest Time Reveals Weed Issues Giant Ragweed #12;Harvest Time Reveals Weed Issues Common Waterhemp #12;Harvest Time Reveals Weed Issues Common Waterhemp What can be done to prevent this

  10. Jill Schroeder Professor, Entomology, Plant Pathology, and Weed Science,

    E-print Network

    Johnson, Eric E.

    Jill Schroeder Professor, Entomology, Plant Pathology, and Weed Science, New Mexico State@nmsu.edu Education 1985 Ph.D. Department of Agronomy (Weed Science), University of Georgia, Athens, GA 1981 M, and Professor of Weed Science Department of Entomology, Plant Pathology, and Weed Science, NMSU Primary Research

  11. WEED CONTROL BPG NOTE 11 Best Practice Guidance

    E-print Network

    WEED CONTROL BPG NOTE 11 Best Practice Guidance for Land Regeneration Introduction Weed control to five years. Weeds compete for nutrients, water and light, and can severely threaten the survival and early growth of newly planted trees. Failure to control weeds represents one of the single most

  12. Weed control and desiccation strategies in chickpea Executive Summary

    E-print Network

    Lawrence, Rick L.

    1 Weed control and desiccation strategies in chickpea Executive Summary Broadleaf weed control is the number one priority for chickpea growers according to surveys from 2000 to 2005. Broadleaf weeds production. The loss of pyridate in 2003 for postemergence weed control limits current herbicide options

  13. Weed Biology and Management 5, 6976 (2005) RESEARCH PAPER

    E-print Network

    Lehmann, Johannes

    2005-01-01

    Weed Biology and Management 5, 69­76 (2005) RESEARCH PAPER Weed composition and cover after three, could lead to increased weed problems for agricultural production. This experiment was conducted to assess weed pressure and species composition on plots receiving various inorganic and organic soil

  14. Nevada's Noxious Weed Program Nevada Department of Agriculture

    E-print Network

    Nowak, Robert S.

    Nevada's Noxious Weed Program Nevada Department of Agriculture Dawn Rafferty, State Weed Program Coordinator #12;NEVADA'S NOXIOUS WEED LAW "...I didn't know yellow starthistle was illegal...." #12;What is a noxious weed? Legal definition (NRS 555.005) "any species of plant which is, or is likely to be

  15. RESEARCH ARTICLE Evidence for weed quantity as the major information

    E-print Network

    Paris-Sud XI, Université de

    RESEARCH ARTICLE Evidence for weed quantity as the major information gathered by organic farmers for weed management Marion Casagrande & Nathalie Joly & Marie-Hélène Jeuffroy & Christine Bouchard has several drawbacks such as difficult weed management. Indeed weeds can reduce crop yields

  16. "Digital Sampling": Mapping Weed Presence in Fallow Fields

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Growers need maps of the distribution of weeds in their fields to reduce herbicide use with site-specific weed management (SSWM). Remote sensing is key to successful weed mapping and sophisticated hyper- and multi-spectral image-based systems appear promising for detecting weed patches and identifyi...

  17. CONTROL OF HAIRY FLEABANE AND OTHER PROBLEM WEEDS IN

    E-print Network

    Hanson, Brad

    2/21/2012 1 CONTROL OF HAIRY FLEABANE AND OTHER PROBLEM WEEDS IN PEACH ORCHARDS Brad Hanson Cooperative Extension Weed Specialist December 13, 2011 NSJV Cling Peach Day Modesto, CA What do we spend on weed control? 2009 cost study ­ Day et al. (fresh mkt peach) Annual costs for weed mgt $74 ­ winter

  18. [Effects of weeding methods on weed community and its diversity in a citrus orchard in southwest Zhejiang].

    PubMed

    Yao, He-Jin; Jin, Zong-Lai; Yang, Wei-Bin; Zhao, Jian-Hua; Zhang, Fan

    2010-01-01

    By using the research methods of ecological community, the effects of different weed management strategies including chemical weeding, manual weeding, and their combination on the weed community and its diversity in a citrus chard of main orange producing region in Quzhou City, Zhejiang Province were studied from June 2005 to May 2008. In control plots, there were 75 species and 25 families of weeds; after chemical weeding, manual weeding, and their combination, there were 46 species and 17 families, 59 species and 20 families, and 51 species and 18 families of weeds, respectively. The Margalef's species richness index, Shannon's diversity index, and Shannon's evenness index were the lowest after chemical weeding, but the highest after manual weeding, suggesting that chemical weeding had the greatest effects on the weed diversity in the citrus orchard. It was suggested that to sufficiently control the weeds while to maintain the weed diversity in the orchard weeds in southwest Zhejiang, the combination of chemical and manual weeding would be the best management strategy. PMID:20387418

  19. 237-Response of a weed community to nitrogen fertilization -Response of a weed community to nitrogen fertilization

    E-print Network

    Leps, Jan "Suspa"

    237- Response of a weed community to nitrogen fertilization - Response of a weed community-mail KRIVAN%CSEARN@SEARN; Abstract. The effect of nitrogen fertilizers on the composition of a weed community effect on the composition of the weed community. The results suggest that both the direct effect

  20. Noxious Weed Survey of Peterson Air Force Base October 31, 2003

    E-print Network

    Noxious Weed Survey of Peterson Air Force Base October 31, 2003 Prepared For: Peterson Air Force WEED STATUS BY SPECIES .................................................................................................. 17 APPENDIX 1: NOXIOUS WEED MAPS

  1. Suggestions for Weed Control in Sorghum

    E-print Network

    Baumann, Paul A.; Coffman, Cloyce G.

    2001-05-04

    to 12 inches tall, and sorghum is 5 to 30 inches tall and before head emergence. Application timing is very weed-specific so CONSULT THE LABEL for weed size limitations per application rate. Use drop nozzles for applications in sorghum over 20 inches... for specific weeds controlled) Banvel ? 4 (dicamba) BASF 0.5 pt. Postemergence to sorghum from spike to 15 inches tall. To minimize potential for injury, treat when sorghum is 3 to 5 inches tall. Use drop nozzles on sorghum over 8 inches tall to keep spray out...

  2. Control of Weeds in Rice Fields.

    E-print Network

    Laude, H. H. (Hilmer Henry)

    1918-01-01

    for the production of the crop. Weeds, as a serious pest, were not known on this new land. After a fetv yeaas of continuous cropping, however, they became -abundant. The common practice of moving to new land every two to four pears mas effective in distributing... numerous noxious weeds; throughout the rice belt, particularly the older producing districts. The usual farming practices were not plsinned to destroy or control weeds. When one field became too foul another mas secured. Rice groTiring coon developed...

  3. EBIPM 2013 planner for preventing weed invasion

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Using a calendar format, this publication is designed for land managers to make management decisions for preventing weed invasions in a timely manner. For each month there are recommendations for wee prevention management actions....

  4. Using Weeds and Wildflowers to Study Plants.

    ERIC Educational Resources Information Center

    Nowak, Nancy

    1984-01-01

    Offers suggestions for activities in which local weeds and wildflowers are used to study a variety of topics. These topics include classification, ecological succession, and mapping. Also lists the types of experiments students can perform with these plants. (JN)

  5. WEED MANAGEMENT IN POTATOES WITH SPARTAN HERBICIDE

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Spartan (sulfentrazone) is a new herbicide for weed management in potatoes. Sulfentrazone applied preemergence controls hairy and black nightshade, redroot pigweed, common lambsquarters, and kochia in potatoes. Spartan may be tank mixed with metribuzin, s-metolachlor, rimsulfuron, pendimethalin, o...

  6. Weed Control Research in Sugar Beets. 

    E-print Network

    Wiese, A. F.; Scott, P. R.; Lavake, D. E.; Winter, S. R.; Owen, D. F.

    1975-01-01

    BULLETIN ' THE TEXAS AGRICULTURAL EXPERIMENT STATION1 J. E. Miller, Director1 Texas A&M University1 College Station, Texas r B-1158 November 1975 WEED CONTROL RESEARCH IN SUGAR BEETS A. F. Wiese, P. R. Scott, D. E. Lavake, S. R. Winter and D... in 1964. the Panhandle. : Ineffective weed control methods and high hoeing ' costs, excessive nitrogen fertilization, and leaf spot Preplant Incorporation I disease have created problems for sugar beet The effectiveness of preplant herbicides...

  7. Weed control using allelopathic crop plants.

    PubMed

    Leather, G R

    1983-08-01

    The concept that some crop plants may be allelopathic to common weeds of agricultural lands is receiving greater attention as an alternative weed control strategy. Several crops showing promise are: grain and forage species such as barley (Hordeum), oat (A vena), fescue (Festuca), and sorghum (Sorghum), and the agronomic species of corn (Zea) and sunflower (Helianthus). Among the problems that hinder the conclusive demonstration of allelopathic effects of crop plants are the loss of that capacity through selection and the variability among cultivars. Recent studies to evaluate the allelopathic potential of crop plants have shown that several sunflower varieties inhibit the germination and growth of associated weeds and to a greater extent than found in several biotypes of native sunflower. Aqueous extracts of dried sunflower and rape tissue inhibited or stimulated germination and growth of weeds, and the response depended upon the source of extract, the extract concentration, and the weed species tested. The validity of bioassay results was tested in a 5-year field study with sunflower and oat grown in rotation. Weed density increased in all plots but the extent of increase was significantly less in plots of sunflower than in control plots. The use of crop plants with increased allelochemical production could limit the need for conventional herbicides to early season application with late season control provided by the crop. PMID:24407794

  8. Weed escapes and delayed weed emergence in glyphosate-resistant soybean

    Technology Transfer Automated Retrieval System (TEKTRAN)

    During 2001 and 2002, field experiments were conducted in soybean crops at four Minnesota locations with the aim of studying the effects of different glyphosate treatments (one-pass glyphosate, two-pass glyphosate) on weed control and weed community composition by focusing on the identity and abunda...

  9. Weed seed production, crop planting pattern, and mechanical weeding in wheat

    Microsoft Academic Search

    Shana K. Mertens

    2002-01-01

    Experiments were carried out to investigate weed seed production in widely spaced spring wheat crops that received aggressive mechanical weed control (hoeing and harrowing) compared with that in narrowly spaced crops receiving less aggressive mechanical control (harrowing only). Three species (wild buckwheat [Polygonum convolvulus], ladysthumb [Polygonum persicaria], and common chickweed [Stellaria media]) were studied in three row-spacing treatments (10, 20,

  10. SHIFTS IN VINEYARD WEED SEED BANK COMPOSITION IN REPONSE TO ORGANIC AND CONVENTIONAL WEED CONTROL PRACTICES

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The aim of this research was to compare the organic weed control practice, soil cultivation, to the conventional practice, applications of the herbicide, glyphosate, in terms of their effects on weed seed bank in a vineyard system. The experiment was conducted in a commercial winegrape vineyard in t...

  11. The Role of Seed Ecology in Improving Weed Management Strategies in the Tropics

    Microsoft Academic Search

    Bhagirath S. Chauhan; David E. Johnson

    2010-01-01

    Weed seed banks reflect past weed populations and management practices and are the source of weed infestations to come. The factors affecting weed seed germination, however, are often poorly understood. Depleting the soil seed bank and influencing germination patterns are common goals of enduring cultural weed management practices. Greater understanding of the factors influencing the germination of weed seeds could

  12. Horticultural & Forest crops 2014 Floral Crops: Weed Control in Greenhouses 5-37

    E-print Network

    Liskiewicz, Maciej

    Horticultural & Forest crops 2014 Floral Crops: Weed Control in Greenhouses 5-37 Weed Control in Greenhouses Jeffrey F. Derr, Extension Weed Scientist, Hampton Roads AREC Nonchemical Control Hand-weeding and good sanitation are the safest ways to control weeds in greenhouses. remove weeds from plugs or liners

  13. Weed control in rose-scented geranium (Pelargonium spp).

    PubMed

    Kothari, Sushil K; Singh, Chandra P; Singh, Kamla

    2002-12-01

    Abstract: Field investigations were carried out during 1999 and 2000 to identify effective chemical/ cultural methods of weed control in rose-scented geranium (Pelargonium spp). The treatments comprised pre-emergence applications of oxyfluorfen (0.15, 0.20 and 0.25 kg AI ha(-1)) and pendimethalin (0.50, 0.75 and 1.00kg AI ha(-1)), successive hand weeding, hoeing and mulching using spent of lemon grass (at 5 tonnes ha(-1)) 45 days after planting (DAP), three hand-weedings 30, 60 and 90 DAP, weed-free (frequent manual weeding) and weedy control. Broad-leaf weeds were more predominant than grass and sedge weeds, accounting for 85.8% weed density and 93.0% weed dry weight in 1999 and 77.2% weed density and 93.9% weed dry weight in 2000. Unrestricted weed growth significantly reduced geranium oil yield, by 61.6% and 70.6% in 1999 and 2000, respectively. Pre-emergence application of pendimethalin (0.75-1.00 kgAI ha(-1)) or oxyfluorfen (0.25 kg AI ha(-1)), successive hand-weeding, hoeing and mulching and three hand-weedings were highly effective in reducing weed density and dry weight and gave oil yield comparable to the weed-free check. Application of oxyfluorfen (0.15 or 0.20 kg AI ha(-1)) and pendimethalin (0.50 kg AI ha(-1)) were less effective in controlling the weed species in geranium. None of the herbicides impaired the quality of rose-scented geranium oil measured in terms of citronellol and geraniol content. PMID:12477000

  14. LESS KNOWN USES OF WEEDS AS MEDICINAL PLANTS

    PubMed Central

    Sahu, T. R.

    1984-01-01

    In this paper the author presents medicinal or otherwise useful weed species with details of family, vernacular name and its medicinal utility. Information on other general economic importance of medicinal weeds is also described here. PMID:22557414

  15. An ultrasonic system for weed detection in cereal crops.

    PubMed

    Andújar, Dionisio; Weis, Martin; Gerhards, Roland

    2012-01-01

    Site-specific weed management requires sensing of the actual weed infestation levels in agricultural fields to adapt the management accordingly. However, sophisticated sensor systems are not yet in wider practical use, since they are not easily available for the farmers and their handling as well as the management practice requires additional efforts. A new sensor-based weed detection method is presented in this paper and its applicability to cereal crops is evaluated. An ultrasonic distance sensor for the determination of plant heights was used for weed detection. It was hypothesised that the weed infested zones have a higher amount of biomass than non-infested areas and that this can be determined by plant height measurements. Ultrasonic distance measurements were taken in a winter wheat field infested by grass weeds and broad-leaved weeds. A total of 80 and 40 circular-shaped samples of different weed densities and compositions were assessed at two different dates. The sensor was pointed directly to the ground for height determination. In the following, weeds were counted and then removed from the sample locations. Grass weeds and broad-leaved weeds were separately removed. Differences between weed infested and weed-free measurements were determined. Dry-matter of weeds and crop was assessed and evaluated together with the sensor measurements. RGB images were taken prior and after weed removal to determine the coverage percentages of weeds and crop per sampling point. Image processing steps included EGI (excess green index) computation and thresholding to separate plants and background. The relationship between ultrasonic readings and the corresponding coverage of the crop and weeds were assessed using multiple regression analysis. Results revealed a height difference between infested and non-infested sample locations. Density and biomass of weeds present in the sample influenced the ultrasonic readings. The possibilities of weed group discrimination were assessed by discriminant analysis. The ultrasonic readings permitted the separation between weed infested zones and non-infested areas with up to 92.8% of success. This system will potentially reduce the cost of weed detection and offers an opportunity to its use in non-selective methods for weed control. PMID:23443401

  16. Table 1. Summary of weed seedbank distribution, diversity (number of species per field) and density across all farms Unit Total Weeds Average Highest Lowest

    E-print Network

    Hayden, Nancy J.

    Table 1. Summary of weed seedbank distribution, diversity (number of species per field) and density across all farms Unit Total Weeds Average Highest Lowest Total Identified Weed Species number 67 13 21 5 Total Identified Weed Species Densityb no./ft 2 274 1081 30 Total Identified Broadleaf Weed Species

  17. Weed Management in Rice?Based Cropping Systems in Africa

    Microsoft Academic Search

    J. Rodenburg; D. E. Johnson

    2009-01-01

    Weed competition is a major constraint in all the rice production systems in Africa. In addition to the costs of weed control, weeds account for yield losses estimated to be at least 2.2 million tons per year in sub?Saharan Africa, valued at $1.45 billion, and equating to approximately half the current total imports of rice to this region. Important weeds

  18. Terbacil and Oryzalin Herbicides Effectively Control Weeds in Lingonberry

    Microsoft Academic Search

    Mark D. Anderson; Elden J. Stang

    1994-01-01

    Terbacil 157 g\\/ha (5 oz\\/acre) or 314 g\\/ha (10 oz\\/acre) and oryzalin 4.7 liteis\\/ha (2 qt\\/acre) provided satisfactory weed control in lingonberry plantings. Lingonberry plantings were nearly weed free 6 weeks after initial application. Untreated and napropa-mide treated plots with inadequate weed control had weeds large enough 6 weeks after application to cause substantial shading of young lingonberry transplants, resulting

  19. Guidelines for management of noxious weeds at Hanford

    SciTech Connect

    Roos, R.C.; Malady, M.B.

    1995-10-27

    Integrated Pest Management Services is responsible for management and control of noxious weeds on the Hanford Site. Weed species and populations are prioritized and objective defined, according to potential site and regional impact. Population controls are implemented according to priority. An integrated approach is planned for noxious weed control in which several management options are considered and implemented separately or in coordination to best meet management objectives. Noxious weeds are inventories and monitored to provide information for planning and program review.

  20. Hard to Control Weeds Are you battling smutgrass?

    E-print Network

    Watson, Craig A.

    Hard to Control Weeds Are you battling smutgrass? What new herbicides are available for pasture weed control? Do you really have Johnsongrass? How do you control bracken fern? Can I really calibrate. Every year we are challenged with new questions, problems, and sometimes, new weeds. It is our goal

  1. REVIEW ARTICLE Innovations in parasitic weeds management in legume crops.

    E-print Network

    Paris-Sud XI, Université de

    REVIEW ARTICLE Innovations in parasitic weeds management in legume crops. A review Diego Rubiales Science+Business Media B.V. 2011 Abstract Parasitic weeds decrease severely the production of major grain and forage legumes. The most economically damaging weeds for temperate legumes are broomrapes, in particular

  2. WEED MANAGEMENT AND HERBICIDE PERFORMANCE DURING DROUGHT CONDITIONS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Low soil moisture increases the competition for water between weeds and the crop making weed control even more important when water is scarce. Drought tolerant weeds develop extensive root systems early and take advantage of limited water making them more competitive and difficult to control then w...

  3. Weed control through seedling abrasion with an organic fertilizer

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Many tools exist to control weeds in organic crops, and each has utility in specific situations. Nevertheless, surveys of organic farmers indicate that weed management often is second only to labor supply as their main bottleneck for success. Consequently, new tactics for managing weeds are desirabl...

  4. Weeds of Central, Southern and Eastern Arabian Peninsula

    Microsoft Academic Search

    S. A. Chaudhary; C. Parker; L. Kasasian

    1981-01-01

    A list of weeds of agricultural areas in the central, southern and eastern Arabian Peninsula is presented along with the maximum intensities of weed infestation resulting from these plants. Although each country studied or a region within a country has a particular set of weeds causing severe infestation, in general the species of greatest importance common to the whole of

  5. Weed Community Response to No-Till in North America

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Scientists and producers in Ukraine are interested in no-till crop production, but are concerned about weed management. In North America, producers have used no-till systems for several decades without increasing weed community density in croplands. Initially, weed density escalated with no-till, ...

  6. 7 CFR 201.52 - Noxious-weed seeds.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ...2012-01-01 2012-01-01 false Noxious-weed seeds. 201.52 Section 201.52...Administration of the Act § 201.52 Noxious-weed seeds. (a) The determination of...bulblets, or tubers of individual noxious weeds present per unit weight should be...

  7. Weed Control in Field Crops Table of Contents

    E-print Network

    Liskiewicz, Maciej

    Weed Control in Field Crops Table of Contents Chemical.........................................................................5-8 Herbicide site of action for reducing the risk of developing herbicide-resistant weeds...................................................................................5-43 Table 5.15 - Susceptibility of Pasture Weeds to Recommended Herbicide Treatments

  8. 7 CFR 201.16 - Noxious-weed seeds.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ...2010-01-01 2010-01-01 false Noxious-weed seeds. 201.16 Section 201.16 Agriculture...Agricultural Seeds § 201.16 Noxious-weed seeds. (a) Except for those kinds of noxious-weed seeds shown in paragraph (b) of this...

  9. 7 CFR 201.52 - Noxious-weed seeds.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ...2011-01-01 2011-01-01 false Noxious-weed seeds. 201.52 Section 201.52...Administration of the Act § 201.52 Noxious-weed seeds. (a) The determination of...bulblets, or tubers of individual noxious weeds present per unit weight should be...

  10. 7 CFR 201.52 - Noxious-weed seeds.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ...2010-01-01 2010-01-01 false Noxious-weed seeds. 201.52 Section 201.52...Administration of the Act § 201.52 Noxious-weed seeds. (a) The determination of...bulblets, or tubers of individual noxious weeds present per unit weight should be...

  11. 7 CFR 201.52 - Noxious-weed seeds.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ...2013-01-01 2013-01-01 false Noxious-weed seeds. 201.52 Section 201.52...Administration of the Act § 201.52 Noxious-weed seeds. (a) The determination of...bulblets, or tubers of individual noxious weeds present per unit weight should be...

  12. 7 CFR 201.52 - Noxious-weed seeds.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ...2014-01-01 2014-01-01 false Noxious-weed seeds. 201.52 Section 201.52...Administration of the Act § 201.52 Noxious-weed seeds. (a) The determination of...bulblets, or tubers of individual noxious weeds present per unit weight should be...

  13. 7 CFR 201.16 - Noxious-weed seeds.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ...2014-01-01 2014-01-01 false Noxious-weed seeds. 201.16 Section 201.16 Agriculture...Agricultural Seeds § 201.16 Noxious-weed seeds. (a) Except for those kinds of noxious-weed seeds shown in paragraph (b) of this...

  14. Texas High Plains Vegetable & Weed Control Research Program

    E-print Network

    Mukhtar, Saqib

    Texas High Plains Vegetable & Weed Control Research Program Research Summary Reports 2004 - 2005 of Herbicides on Crop Injury, Weed Control and Yield in Drip-Irrigated Pumpkins (2005) 28 LEAFY GREENS Evaluation of Herbicides for Weed Control and Crop Injury in Garden Beets (2004-2005) 30 Herbicide Evaluation

  15. Weeds-wheat discrimination using hyperspectral imagery Xavier Hadoux1

    E-print Network

    Paris-Sud XI, Université de

    Weeds-wheat discrimination using hyperspectral imagery Xavier Hadoux1 *, Nathalie Gorretta1 between weeds and crop by computer vision remains today a major obstacle to the promotion of localized weeding practices. The objective of the present study was to evaluate the potential of hyperspectral

  16. 7 CFR 201.16 - Noxious-weed seeds.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ...2012-01-01 2012-01-01 false Noxious-weed seeds. 201.16 Section 201.16 Agriculture...Agricultural Seeds § 201.16 Noxious-weed seeds. (a) Except for those kinds of noxious-weed seeds shown in paragraph (b) of this...

  17. RESEARCH ARTICLE Biodegradable mulch instead of polyethylene for weed

    E-print Network

    Paris-Sud XI, Université de

    RESEARCH ARTICLE Biodegradable mulch instead of polyethylene for weed control of processing tomato P. Mill.) in Spain achieving a generally high weed control but caus- ing a serious waste problem which should provide high yield, high weed control and be economically available. For 3 years, the same

  18. 7 CFR 201.16 - Noxious-weed seeds.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ...2011-01-01 2011-01-01 false Noxious-weed seeds. 201.16 Section 201.16 Agriculture...Agricultural Seeds § 201.16 Noxious-weed seeds. (a) Except for those kinds of noxious-weed seeds shown in paragraph (b) of this...

  19. Texas High Plains Vegetable & Weed Control Research Program

    E-print Network

    Mukhtar, Saqib

    Texas High Plains Vegetable & Weed Control Research Program Research Summary Reports 2008 Texas W. Wallace, Ph.D. Extension Vegetable & Weed Specialist Alisa K. Petty Research Technician #12 RESULTS OF HIGH PLAINS TRIALS 8 Herbicides and Weed Control Herbicide screen for mustard and collard

  20. Interannual variation in weed biomass on arable land in Sweden

    E-print Network

    Palmer, Michael W.

    Interannual variation in weed biomass on arable land in Sweden P MILBERG, E HALLGREN* & M W PALMER 1999 Summary Data were analysed on weed biomass from untreated plots in 2672 ®eld experiments conducted) among years in the biomass of annual weeds per square metre was 29% in autumn-sown crops. In spring

  1. Texas High Plains Vegetable & Weed Control Research Program

    E-print Network

    Mukhtar, Saqib

    Texas High Plains Vegetable & Weed Control Research Program Research Summary Reports 2006 Texas Experiment Station Russell W. Wallace Extension Vegetable & Weed Specialist Alisa K. Petty Research ................................................... 7 RESULTS OF HIGH PLAINS TRIALS 8 Herbicides and Weed Control Evaluation of Firestorm Applied

  2. Weeds Sampling for Map Reconstruction: a Markov Random Field Approach

    E-print Network

    Boyer, Edmond

    Weeds Sampling for Map Reconstruction: a Markov Random Field Approach M. Bonneau1,2 , S. Gaba2 , N In the past 15 years, there has been a growing interest for the study of the spatial repartition of weeds of these methods is that they are based on in situ collection of data about weeds spatial repartition. A crucial

  3. ORIGINAL PAPER Development and validation of a weed screening tool

    E-print Network

    Schweik, Charles M.

    ORIGINAL PAPER Development and validation of a weed screening tool for the United States Anthony L 2011 Ó Springer Science+Business Media B.V.(outside the USA) 2011 Abstract The Australian weed risk of weeds and invasive plants into new areas. On average, the Australian model identifies major

  4. 7 CFR 201.16 - Noxious-weed seeds.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ...2013-01-01 2013-01-01 false Noxious-weed seeds. 201.16 Section 201.16 Agriculture...Agricultural Seeds § 201.16 Noxious-weed seeds. (a) Except for those kinds of noxious-weed seeds shown in paragraph (b) of this...

  5. From Conventional to Organic: Weed Management Principles for the

    E-print Network

    Maxwell, Bruce D.

    From Conventional to Organic: Weed Management Principles for the Transition Years Fabián Menalled.montana.edu/cropweeds #12;A Disclaimer · This is not going to be a "traditional" weed extension presentation · Your best weed management tool is located between your ears www.forages.oregonsate.edu #12;Today, we'll talk more

  6. Deciphering the evolution of herbicide resistance in weeds

    E-print Network

    California at Davis, University of

    Deciphering the evolution of herbicide resistance in weeds Christophe De´lye1 , Marie Jasieniuk2, University of California, Davis, CA 95616, USA Resistance to herbicides in arable weeds is increasing rapidly in weed populations can only be fully elucidated by focusing on evolutionary dynamics and implementing

  7. WEEDS AS HOSTS FOR THE SOUTHERN ROOT-KNOT NEMATODE

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The southern root-knot nematode, Meloidogyne incognita, can reproduce on many different plants, including many weeds, but the amount of reproduction that occurs on weeds is not well documented. This study was conducted to document the relative host status of weeds common in Georgia. Seeds of cotton,...

  8. Agricultural weed research: a critique and two proposals

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Two broad aims drive weed science research: improved management and improved understanding of weed biology and ecology. In recent years, agricultural weed research addressing these two aims has effectively split into separate sub-disciplines despite repeated calls for greater integration. While some...

  9. Organic weed control in two watermelon variety trials

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Weeds are often cited as the number one pest problem in organic vegetable production systems. The weed control methods employed must be organically approved and fully integrated into the organic production system. The objective of these experiments was to investigate the impact of different weed c...

  10. The Effect of Laser Treatment as a Weed Control Method

    Microsoft Academic Search

    Solvejg K. Mathiassen; Thomas Bak; Svend Christensen; Per Kudsk

    2006-01-01

    A laser beam directed towards weeds can be an efficient weed control method as an alternative to herbicides. Lasers may deliver high-density energy to selected plant material, raising the temperature of the water in the plant cells and thereby stop or delay the growth. A commercial use of lasers for weed control, however, require a systematic investigation of the relationship

  11. Effects of repeated clover undersowing, green manure ley and weed harrowing on weeds and yields in organic cereals

    Microsoft Academic Search

    Helge Sjursen; Lars Olav Brandsæter; Jan Netland

    2012-01-01

    Cover crops can be used to reduce leaching and erosion, introduce variability into crop rotation and fix nitrogen (N) for use by the main crops, less is however known about effects on weeds. The effects on weed seed bank, weed growth and grain yield of 4 years of annual undersown clover and ryegrass alone and in combination, and one of

  12. Effects of repeated clover undersowing, green manure ley and weed harrowing on weeds and yields in organic cereals

    Microsoft Academic Search

    Helge Sjursen; Lars Olav Brandsæter; Jan Netland

    2011-01-01

    Cover crops can be used to reduce leaching and erosion, introduce variability into crop rotation and fix nitrogen (N) for use by the main crops, less is however known about effects on weeds. The effects on weed seed bank, weed growth and grain yield of 4 years of annual undersown clover and ryegrass alone and in combination, and one of

  13. Characterization of an EST database for the perennial weed leafy spurge: an important resource for weed biology research

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Genomics programs in the weed science community have not developed as rapidly as that of other crop, horticultural, forestry, and model plant systems. Development of genomic resources for selected model weeds are expected to enhance our understanding of weed biology, just as they have in other plant...

  14. Effects of controlled weed densities and soil types on soil nitrate accumulation, spruce growth, and weed growth

    Microsoft Academic Search

    Naresh V. Thevathasan; Phillip E. Reynolds; Ralf Kuessner; Wayne F. Bell

    2000-01-01

    Soil nitrate (NO3?) accumulation rates were assessed among seven weed species grown in small plots during the summer of 1997, at a northern Ontario location. Objectives were (1) to quantify soil nitrate accumulation rates at varying weed densities established on three soil types (clay, loam, and sand) and (2) to assess the effects of soil nitrate levels on weed and

  15. Suggestions For Weed Control In Cotton 

    E-print Network

    Baumann, Paul A.; Lemon, Robert G.

    2007-07-03

    ? Magnum or Dual II ? Magnum 1.0?1.33 pt (metolachlor) Syngenta Minimum of 10 gal water or liquid fertilizer. Preplant incorporated or preemergence. Do not apply on sand or loamy sand soils. Do not apply to furrow-planted cotton. Apply... and broadleaf weeds Refer to label for weed- specific rates. Dual ? Magnum or DuaI II ? Magnum 1.25?2.0 pt (metolachlor) + Caparol ? 4L 1.6?4.8 pt (prometryn) Caparol ? Accu Pak 1.0?3.0 lb Syngenta Minimum of 10 gal water. Preplant...

  16. Suggestions for Weed Control in Sorghum 

    E-print Network

    Baumann, Paul A.; Coffman, Cloyce G.

    2001-05-04

    controlled Product (Herbicide common name) Company Application rate per acre Time to apply Remarks Annual grasses and broadleaf weeds (refer to label for specific weeds controlled) Dual ? 8E or Dual II ? 7.8E Dual II ? Magnum (metolachlor) (s... ? Bicep II ? Magnum (metolachlor + atrazine) Novartis 1.8 to 2.4 qts. 1.6 to 2.1 qts. Same as above. Do not use in Texas except in Texas Panhandle, Gulf Coast and Blacklands areas. Do not use on sand, loamy sand, or sandy loam soils or on soils with less...

  17. Weed Busters: How to Pound Threadleaf Groundsel

    E-print Network

    McGinty, Allan; Hart, Charles R.; Cadenhead, J. F.

    2005-10-05

    L-5470 9/05 How to Pound Threadleaf Groundsel (Senecio) Safe and effective three-step ways to control threadleaf groundsel Weed Treatment Series Allan McGinty, Charles Hart and J. F. Cadenhead Extension Range Specialists The Texas A&M University..., in cooperation with the United States Department of Agriculture. Edward G. Smith, Director, Texas Cooperative Extension, The Texas A&M University System. 1.5M, New T readleaf groundsel, also known as Senecio, is a shrubby perennial weed commonly found...

  18. Weed Control in 'Concord' Grapes in Arkansas

    Microsoft Academic Search

    J. M. Kennedy; R. E. Talbert; J. R. Morris

    1979-01-01

    Midsummer grapehoeing following spring application of diuron (3-(3,4-dichlorophenyl)-1,1-dimethylurea) or simazine (2-chloro-4,6-bis(ethylamino)-s-triazine) plus paraquat (1,1'-dimethyl-4,4'-bipyridinium ion) adequately controlled weeds growing in grapes (Vitis labrusca L.). When grapehoeing was used to control grape root borer ((Vitacea polistiformis Harris) lower initial rates of preemergence herbicide could be used. An additional half-rate of herbicide was required after grapehoeing to maintain weed control through the

  19. Detecting Weed Infestations in Soybean Using Remote Sensing.

    NASA Astrophysics Data System (ADS)

    Clay, S. A.; Chang, J.; Clay, D. E.; Dalsted, K.; Reese, C.

    2007-12-01

    Can weed distribution maps be developed from remote sensed reflectance data? When are the appropriate times to collect these data during the season? What wavebands can be used to distinguish weedy from weed- free areas? This research examined if and when reflectance could be used to distinguish between weed-free and weed-infested (mixed species) areas in soybean and to determine the most useful wavebands to separate crop, weed, and soil reflectance differences. Treatments in the two-year study included no vegetation (bare soil), weed-free soybean, and weed-infested soybean and, in one year, 80% corn residue cover. Reflectance was measured at several sampling times from May through September in 2001 and 2002 using a hand-held multispectral radiometer equipped with band-limited optical interference filters (460 - 1650 nm). Pixel resolution was 0.8-m. Reflectance in the visible spectral range (460 to 700 nm) generally was similar among treatments. In the near-infrared (NIR) range (>700 to 1650 nm), differences among treatments were observed from soybean growth stage V-3 (about 4 weeks after planting) until mid-July to early August depending on crop vigor and canopy closure (76 cm row spacing in 2001 and 19 cm row spacing in 2002). Reflectance rankings in the NIR range when treatments could be differentiated were consistent between years and, from lowest to highest reflectance, were soil < weed-free < weed-infested areas. Increased reflectance from weed-infested areas was most likely due to increased biomass and canopy cover. Residue masked differences between weed-free and weed- infested areas during the early stages of growth due to high reflectance from the residue and reduced weed numbers in these areas. These results suggest that NIR spectral reflectance collected prior to canopy closure can be used to distinguish weed-infested from weed-free areas.

  20. Virus infection of a weed increases vector attraction to and vector fitness on the weed.

    PubMed

    Chen, Gong; Pan, Huipeng; Xie, Wen; Wang, Shaoli; Wu, Qingjun; Fang, Yong; Shi, Xiaobin; Zhang, Youjun

    2013-01-01

    Weeds are important in the ecology of field crops, and when crops are harvested, weeds often become the main hosts for plant viruses and their insect vectors. Few studies, however, have examined the relationships between plant viruses, vectors, and weeds. Here, we investigated how infection of the weed Datura stramonium L. by tomato yellow leaf curl virus (TYLCV) affects the host preference and performance of the TYLCV vector, Bemisia tabaci (Gennadius) Q. The results of a choice experiment indicated that B. tabaci Q preferentially settled and oviposited on TYLCV-infected plants rather than on healthy plants. In addition, B. tabaci Q performed better on TYLCV-infected plants than on healthy plants. These results demonstrate that TYLCV is indirectly mutualistic to B. tabaci Q. The mutually beneficial interaction between TYLCV and B. tabaci Q may help explain the concurrent outbreaks of TYLCV and B. tabaci Q in China. PMID:23872717

  1. WEED SCIENCE Evaluation of Trifloxysulfuron plus Prometryn for Weed Control in Cotton (Gossypium hirsutum L.)

    Microsoft Academic Search

    D. M. Dodds; M. T. Kirkpatrick; L. T. Barber; D. B. Reynolds

    2008-01-01

    Glyphosate-resistant cotton (Gossypium hirsutum L.) has been widely accepted by cot- ton producers. Because of topical application restrictions, postemergence-directed (PD) or late postemergence-directed (LAYBY) applications are typically needed to obtain season long weed control. Trifloxysulfuron and prometryn are each broad-spectrum herbicides used for PD weed control in cotton and are currently marketed as a premix. The objective of this study

  2. Molecular Biology and Genomics: New Tools for Weed Science

    NSDL National Science Digital Library

    Patrick Tranel (University of Illinois; College of Agricultural, Consumer, and Environmental Sciences)

    2009-03-01

    Some plant species are particularly well adapted to environments disturbed by humans. Often such species are invasive and problematic, and thus are classified as weeds. Despite our best efforts to manage weeds, they continue to interfere with crop production. There is clearly much to learn about weeds, information that could aid in weed management and improve competitiveness in nonweedy species. The tools of molecular biology have been enlisted in ongoing efforts to manage weeds, most notably in the development and commercialization of crop plants tailored to resist certain herbicides. Molecular biology also has been used to gain a better understanding of how weeds compete and interact with neighboring plants, survive harsh environmental conditions, and evolve resistance to the herbicides used to control them. The next generation of molecular biology tools, such as genomic resources, may yield novel weed management strategies and shed new light on what makes plants weedy.

  3. Roundup Resistant Weeds Changing Weedscapes of Minnesota

    E-print Network

    Minnesota, University of

    · Glyphosate 2000's ­ Mare's Tail (not MN) ­ Waterhemp ­ Ragweeds #12;Perennial Weeds, 14 Year Study, Nashua identified worldwide. #12;Glyphosate resistant marestail (3" rosette at treatment) Glyphosate resistant marestail (3" rosette at treatment) *Glyphosate rates in lbs. acid equivalent per acre. 24 DAT.Source: Univ

  4. Jimson "Loco" Weed Abuse in Adolescents.

    ERIC Educational Resources Information Center

    Shervette, Robert E., III; And Others

    1979-01-01

    Over a 3-year period, 29 adolescent patients were hospitalized because of intentional Jimson weed ingestion. Their records were reviewed for the presence of signs and symptoms of atropine/scopolamine toxicity, clinical course, treatment, and outcome. Journal availability: Arthur Retlaw and Associates, Inc., Suite 2080, 1603 Orrington Avenue,…

  5. Bio-gas production from alligator weeds

    NASA Technical Reports Server (NTRS)

    Latif, A.

    1976-01-01

    Laboratory experiments were conducted to study the effect of temperature, sample preparation, reducing agents, light intensity and pH of the media, on bio-gas and methane production from the microbial anaerobic decomposition of alligator weeds (Alternanthera philoxeroides. Efforts were also made for the isolation and characterization of the methanogenic bacteria.

  6. Organic weed control in Cowpea: Summer 2006

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Cowpea is a major vegetable crop within the state of Oklahoma. It is utilized as both a processing crop by the canning industry and as a fresh market crop for farmer’s and roadside markets. Traditionally weed control in this crop is primarily handled with preemergence and some postemergence herbicid...

  7. Fertility Effects on Weed & Crop Competition

    Microsoft Academic Search

    Hugh J. Beckie; Robert E. Blackshaw; Louis J. Molnar; Toby Entz; Jim R. Moyer; K. Neil

    Summary A field study was conducted at three locations across western Canada to determine the combined effects of fertilizer timing (fall- or spring-applied), seeding date (late April or late May), seeding rate (recommended or 150% of recommended), and in-crop herbicide rate (50 or 100% of recommended) on weed growth and crop yield. The factorial set of treatments was applied in

  8. Weed Suppression by Seven Clover Species

    Microsoft Academic Search

    Shirley M. Ross; Jane R. King; R Cesar C. Izaurralde; John T. ODonovan

    2001-01-01

    Used as cover crops, clover species may differ in their ability to suppress weed growth. Field trials were conducted in Alberta, Canada to measure the growth of brown mustard [Brassica juncea (L.) Czern.], in mowed and nonmowed production, as influenced by alsike (Trifolium hybridum L.), balansa [T. michelianum Savi var. balansae (Boiss.) Azn.], berseem (T. alexandrinum L.), crimson [T. incarnatum

  9. RNAseq reveals weed-induced PIF3-like as a candidate target to manipulate weed stress response in soybean.

    PubMed

    Horvath, David P; Hansen, Stephanie A; Moriles-Miller, Janet P; Pierik, Ronald; Yan, Changhui; Clay, David E; Scheffler, Brian; Clay, Sharon A

    2015-07-01

    Weeds reduce yield in soybeans (Glycine max) through incompletely defined mechanisms. The effects of weeds on the soybean transcriptome were evaluated in field conditions during four separate growing seasons. RNASeq data were collected from six biological samples of soybeans growing with or without weeds. Weed species and the methods to maintain weed-free controls varied between years to mitigate treatment effects, and to allow detection of general soybean weed responses. Soybean plants were not visibly nutrient- or water-stressed. We identified 55 consistently downregulated genes in weedy plots. Many of the downregulated genes were heat shock genes. Fourteen genes were consistently upregulated. Several transcription factors including a PHYTOCHROME INTERACTING FACTOR 3-like gene (PIF3) were included among the upregulated genes. Gene set enrichment analysis indicated roles for increased oxidative stress and jasmonic acid signaling responses during weed stress. The relationship of this weed-induced PIF3 gene to genes involved in shade avoidance responses in Arabidopsis provide evidence that this gene may be important in the response of soybean to weeds. These results suggest that the weed-induced PIF3 gene will be a target for manipulating weed tolerance in soybean. PMID:25711503

  10. HOME GROUNDS & ANIMALS 2014 Home Ornamentals: Weed Management in Home Ornamental Beds 4-89

    E-print Network

    Liskiewicz, Maciej

    HOME GROUNDS & ANIMALS 2014 Home Ornamentals: Weed Management in Home Ornamental Beds 4-89 Weed Management in Home Ornamental Beds Jeffrey F. Derr, Extension Weed Scientist, Hampton Roads AREC Overview Weed management is necessary in flower beds and for shrub and tree plantings. Weeds reduce

  11. South Carolina Pest Management Handbook for Field Crops -2013 WEED CONTROL IN SUNFLOWER

    E-print Network

    Stuart, Steven J.

    South Carolina Pest Management Handbook for Field Crops - 2013 249 WEED CONTROL IN SUNFLOWER Mike Marshall, Extension Weed Specialist Preplant/Burndown Herbicides for Weed Management in Sunflowers anytime before planting when weeds are small. Use a higher rate for larger weeds. Add a COC (1-2 gal per

  12. South Carolina Pest Management Handbook for Field Crops -2014 WEED CONTROL IN SUNFLOWER

    E-print Network

    Duchowski, Andrew T.

    South Carolina Pest Management Handbook for Field Crops - 2014 262 WEED CONTROL IN SUNFLOWER Mike Marshall, Extension Weed Specialist Preplant/Burndown Herbicides for Weed Management in Sunflowers anytime before planting when weeds are small. Use a higher rate for larger weeds. Add a COC (1-2 gal per

  13. Horticultural & Forest crops 2014 Low-Management Crops and Areas: Christmas Tree Weeds 7-27

    E-print Network

    Liskiewicz, Maciej

    Horticultural & Forest crops 2014 Low-Management Crops and Areas: Christmas Tree Weeds 7-27 Christmas Tree Weeds Jeffrey F. Derr, Extension Weed Scientist, Hampton Roads AREC Weed control. perennial weeds are not likely to become a serious problem in annual crops since they can be removed either

  14. www.btny.purdue.edu/weedscience/ Indiana's Top Ten Most Problematic Weeds

    E-print Network

    Ginzel, Matthew

    www.btny.purdue.edu/weedscience/ Indiana's Top Ten Most Problematic Weeds Glenn Nice Bill Johnson Purdue Extension Weed Science Figure 1. Vince Davis doing weed seedling counts. Weed control practices often have an effect on the weeds we deal with on a year by year basis. Before the development

  15. Research Paper Design and testing of an intra-row mechanical weeding

    E-print Network

    Research Paper Design and testing of an intra-row mechanical weeding machine for corn C. Cordill As an alternative to chemical weed control, mechanical weed control between crop rows can be achieved using standard-row weed control in maize. The object was to non-specifically remove weed plants within the row by enabling

  16. Hyperspectral imagery to discriminate weeds in wheat G. Rabatel*. F. Ougache**

    E-print Network

    Boyer, Edmond

    Hyperspectral imagery to discriminate weeds in wheat G. Rabatel*. F. Ougache** N. Gorretta*, M of hyperspectral imagery for the detection of dicotyledonous weeds in durum wheat during weeding period (end;Hyperspectral imagery to discriminate weeds in wheat 2 weeding operations after crop emergence, because

  17. Optical weed detection and evaluation using reflection measurements

    NASA Astrophysics Data System (ADS)

    Vrindts, Els; De Baerdemaeker, Josse

    1999-01-01

    For the site-specific application of herbicides, the automatic detection and evaluation of weeds is necessary. Since reflectance of crop, weeds and soil differs in visual and near IR wavelengths, there is a potential for using reflection measurements at different wavelengths to distinguish between them. Diffuse reflectance spectra of crop and weed leaves were used to evaluate the possibilities of weed detection with reflection measurements. Fourteen different weed species and four crops were included in the dataset. Classification of the spectra in crop, weeds and soil is possible, based on 3 to 7 narrow wavelength bands. The spectral analysis was repeated for reflectance measurements of canopies. Sugarbeet and Maize and 7 weed species were included in the measurements. The classification into crop and weeds was still possible, suing a limited number of wavelength band ratios. This suggest that reflection measurements at a limited number of wavelength bands could be used to detect and treat weeds in a field. This is a great environmental benefit, as agrochemicals will only be used where they are needed. The possibilities of using optical reflectance for weed detection and treatment in the field are discussed.

  18. A non-chemical system for online weed control.

    PubMed

    Rueda-Ayala, Victor; Peteinatos, Gerassimos; Gerhards, Roland; Andújar, Dionisio

    2015-01-01

    Non-chemical weed control methods need to be directed towards a site-specific weeding approach, in order to be able to compete the conventional herbicide equivalents. A system for online weed control was developed. It automatically adjusts the tine angle of a harrow and creates different levels of intensity: from gentle to aggressive. Two experimental plots in a maize field were harrowed with two consecutive passes. The plots presented from low to high weed infestation levels. Discriminant capabilities of an ultrasonic sensor were used to determine the crop and weed variability of the field. A controlling unit used ultrasonic readings to adjust the tine angle, producing an appropriate harrowing intensity. Thus, areas with high crop and weed densities were more aggressively harrowed, while areas with lower densities were cultivated with a gentler treatment; areas with very low densities or without weeds were not treated. Although the weed development was relatively advanced and the soil surface was hard, the weed control achieved by the system reached an average of 51% (20%-91%), without causing significant crop damage as a result of harrowing. This system is proposed as a relatively low cost, online, and real-time automatic harrow that improves the weed control efficacy, reduces energy consumption, and avoids the usage of herbicide. PMID:25831085

  19. A Non-Chemical System for Online Weed Control

    PubMed Central

    Rueda-Ayala, Victor; Peteinatos, Gerassimos; Gerhards, Roland; Andújar, Dionisio

    2015-01-01

    Non-chemical weed control methods need to be directed towards a site-specific weeding approach, in order to be able to compete the conventional herbicide equivalents. A system for online weed control was developed. It automatically adjusts the tine angle of a harrow and creates different levels of intensity: from gentle to aggressive. Two experimental plots in a maize field were harrowed with two consecutive passes. The plots presented from low to high weed infestation levels. Discriminant capabilities of an ultrasonic sensor were used to determine the crop and weed variability of the field. A controlling unit used ultrasonic readings to adjust the tine angle, producing an appropriate harrowing intensity. Thus, areas with high crop and weed densities were more aggressively harrowed, while areas with lower densities were cultivated with a gentler treatment; areas with very low densities or without weeds were not treated. Although the weed development was relatively advanced and the soil surface was hard, the weed control achieved by the system reached an average of 51% (20%–91%), without causing significant crop damage as a result of harrowing. This system is proposed as a relatively low cost, online, and real-time automatic harrow that improves the weed control efficacy, reduces energy consumption, and avoids the usage of herbicide. PMID:25831085

  20. [Effects of tillage method and herbicide on cornfield weed community].

    PubMed

    Liu, Fangming; Liang, Wenju; Wen, Dazhong

    2005-10-01

    By the method of community ecology, this paper surveyed the weed community in a cornfield at the Shenyang Experimental Station of Ecology, CAS, and studied the effects of tillage method and herbicide on the weed composition, species diversity, and biomass at the experimental site. The results showed that the dominant weed species in the cornfield were Eriochloa villosa, Abutilon theophrasti, Bidens frondosa and Commelina communis, of which, Eriochloa villosa had the highest important value. In non-tillage field without herbicide application, the weed community had larger biomass, higher richness (S) and concentration (C), but lower species diversity (D) and species evenness (J). Herbicide could decrease weed species and inhibit biomass growth significantly in non-tillage field. It was clear that tillage method and herbicide could affect the weed composition, diversity and stability significantly. PMID:16422507

  1. 7 CFR 360.500 - Petitions to add a taxon to the noxious weed list.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ...taxon to the noxious weed lists must provide...taxon to the noxious weed lists are encouraged...be listed as a noxious weed: (a) Identification... (8) Description of control efforts, if established...Dispersal potential (biological characteristics...

  2. 7 CFR 205.206 - Crop pest, weed, and disease management practice standard.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 2013-01-01 false Crop pest, weed, and disease management practice standard...Requirements § 205.206 Crop pest, weed, and disease management practice standard...management practices to prevent crop pests, weeds, and diseases including but not...

  3. 7 CFR 360.302 - Consideration of applications for permits to move noxious weeds.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ...applications for permits to move noxious weeds. 360.302 Section 360.302 Agriculture...SERVICE, DEPARTMENT OF AGRICULTURE NOXIOUS WEED REGULATIONS § 360.302 Consideration of applications for permits to move noxious weeds. Upon the receipt of an...

  4. 7 CFR 360.302 - Consideration of applications for permits to move noxious weeds.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ...applications for permits to move noxious weeds. 360.302 Section 360.302 Agriculture...SERVICE, DEPARTMENT OF AGRICULTURE NOXIOUS WEED REGULATIONS § 360.302 Consideration of applications for permits to move noxious weeds. Upon the receipt of an...

  5. 7 CFR 360.300 - Notice of restrictions on movement of noxious weeds.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ...of restrictions on movement of noxious weeds. 360.300 Section 360.300 Agriculture...DEPARTMENT OF AGRICULTURE NOXIOUS WEED REGULATIONS § 360.300 Notice of restrictions on movement of noxious weeds. No person may move a Federal...

  6. 7 CFR 360.300 - Notice of restrictions on movement of noxious weeds.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ...of restrictions on movement of noxious weeds. 360.300 Section 360.300 Agriculture...DEPARTMENT OF AGRICULTURE NOXIOUS WEED REGULATIONS § 360.300 Notice of restrictions on movement of noxious weeds. No person may move a Federal...

  7. 7 CFR 205.206 - Crop pest, weed, and disease management practice standard.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 2014-01-01 false Crop pest, weed, and disease management practice standard...Requirements § 205.206 Crop pest, weed, and disease management practice standard...management practices to prevent crop pests, weeds, and diseases including but not...

  8. RMRS Weed Biocontrol Research: Past Accomplishments, Current Status, and Future Challenges

    E-print Network

    RMRS Weed Biocontrol Research: Past Accomplishments, Current Status, and Future Challenges RMRS Weed Biontrol Team Accomplishments Report Fiscal Years 2007-2011 USDA Forest Service Rocky Mountain..........................................................................................................................................3 The Weed Biocontrol Research Team

  9. Cooperative Coevolutionary Invasive Weed Optimization and its Application to Nash Equilibrium Search in Electricity Markets

    E-print Network

    Zhang, Richard "Hao"

    Cooperative Coevolutionary Invasive Weed Optimization and its Application to Nash Equilibrium invasive weed optimization (CCIWO) and investigates its performance for global optimization of functions results show efficiency of the proposed method to have more accurate solutions. Keywords-invasive weed

  10. 7 CFR 360.300 - General prohibitions and restrictions on the movement of noxious weeds; permits.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ...restrictions on the movement of noxious weeds; permits. 360.300 Section 360...SERVICE, DEPARTMENT OF AGRICULTURE NOXIOUS WEED REGULATIONS § 360.300 General prohibitions...restrictions on the movement of noxious weeds; permits. (a) No person may...

  11. Noxious Weed Survey of the U.S. Air Force Academy and

    E-print Network

    Noxious Weed Survey of the U.S. Air Force Academy and Farish Outdoor Recreation Area Colorado ....................................................................................... 9 WEED MAPPING RATIONALE FOR SUGGESTED MANAGEMENT PRIORITIES IN TABLE 3............................ 13 NOXIOUS WEED STATUS

  12. 7 CFR 360.305 - Disposal of noxious weeds when permits are canceled.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ...2012-01-01 false Disposal of noxious weeds when permits are canceled. 360.305 ...SERVICE, DEPARTMENT OF AGRICULTURE NOXIOUS WEED REGULATIONS § 360.305 Disposal of noxious weeds when permits are canceled. When a...

  13. 7 CFR 360.501 - Petitions to remove a taxon from the noxious weed lists.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ...Petitions to remove a taxon from the noxious weed lists. 360.501 Section 360.501...DEPARTMENT OF AGRICULTURE NOXIOUS WEED REGULATIONS § 360.501 Petitions to remove a taxon from the noxious weed lists. A person may petition...

  14. 7 CFR 360.305 - Disposal of noxious weeds when permits are canceled.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ...2013-01-01 false Disposal of noxious weeds when permits are canceled. 360.305 ...SERVICE, DEPARTMENT OF AGRICULTURE NOXIOUS WEED REGULATIONS § 360.305 Disposal of noxious weeds when permits are canceled. When a...

  15. 7 CFR 360.305 - Disposal of noxious weeds when permits are canceled.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ...2011-01-01 false Disposal of noxious weeds when permits are canceled. 360.305 ...SERVICE, DEPARTMENT OF AGRICULTURE NOXIOUS WEED REGULATIONS § 360.305 Disposal of noxious weeds when permits are canceled. When a...

  16. 7 CFR 360.300 - Notice of restrictions on movement of noxious weeds.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ...of restrictions on movement of noxious weeds. 360.300 Section 360.300 Agriculture...DEPARTMENT OF AGRICULTURE NOXIOUS WEED REGULATIONS § 360.300 Notice of restrictions on movement of noxious weeds. No person may move a Federal...

  17. 7 CFR 360.501 - Petitions to remove a taxon from the noxious weed lists.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ...Petitions to remove a taxon from the noxious weed lists. 360.501 Section 360.501...DEPARTMENT OF AGRICULTURE NOXIOUS WEED REGULATIONS § 360.501 Petitions to remove a taxon from the noxious weed lists. A person may petition...

  18. 7 CFR 360.302 - Consideration of applications for permits to move noxious weeds.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ...applications for permits to move noxious weeds. 360.302 Section 360.302 Agriculture...SERVICE, DEPARTMENT OF AGRICULTURE NOXIOUS WEED REGULATIONS § 360.302 Consideration of applications for permits to move noxious weeds. Upon the receipt of an...

  19. 7 CFR 360.302 - Consideration of applications for permits to move noxious weeds.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ...applications for permits to move noxious weeds. 360.302 Section 360.302 Agriculture...SERVICE, DEPARTMENT OF AGRICULTURE NOXIOUS WEED REGULATIONS § 360.302 Consideration of applications for permits to move noxious weeds. Upon the receipt of an...

  20. 7 CFR 360.305 - Disposal of noxious weeds when permits are canceled.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ...2014-01-01 false Disposal of noxious weeds when permits are canceled. 360.305 ...SERVICE, DEPARTMENT OF AGRICULTURE NOXIOUS WEED REGULATIONS § 360.305 Disposal of noxious weeds when permits are canceled. When a...

  1. 7 CFR 360.300 - Notice of restrictions on movement of noxious weeds.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ...of restrictions on movement of noxious weeds. 360.300 Section 360.300 Agriculture...DEPARTMENT OF AGRICULTURE NOXIOUS WEED REGULATIONS § 360.300 Notice of restrictions on movement of noxious weeds. No person may move a Federal...

  2. 7 CFR 205.206 - Crop pest, weed, and disease management practice standard.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 2012-01-01 false Crop pest, weed, and disease management practice standard...Requirements § 205.206 Crop pest, weed, and disease management practice standard...management practices to prevent crop pests, weeds, and diseases including but not...

  3. 7 CFR 360.501 - Petitions to remove a taxon from the noxious weed lists.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ...Petitions to remove a taxon from the noxious weed lists. 360.501 Section 360.501...DEPARTMENT OF AGRICULTURE NOXIOUS WEED REGULATIONS § 360.501 Petitions to remove a taxon from the noxious weed lists. A person may petition...

  4. 7 CFR 360.501 - Petitions to remove a taxon from the noxious weed lists.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ...Petitions to remove a taxon from the noxious weed lists. 360.501 Section 360.501...DEPARTMENT OF AGRICULTURE NOXIOUS WEED REGULATIONS § 360.501 Petitions to remove a taxon from the noxious weed lists. A person may petition...

  5. Feeding Preferences of Weed Seed Predators and Effect on Weed Emergence Sharon S. White, Karen A. Renner, Fabian D. Menalled, and Douglas A. Landis*

    E-print Network

    Landis, Doug

    Feeding Preferences of Weed Seed Predators and Effect on Weed Emergence Sharon S. White, Karen A predators and the effect of seed predation on weed emergence. Feeding choice studies were completed seed consumption did not differ between these two weed species. All invertebrates consumed fewer

  6. While soil-applied herbicides can be quite valuable in weed control, misuse can cause crop injury or failure to control weeds. This guide

    E-print Network

    Maxwell, Bruce D.

    While soil-applied herbicides can be quite valuable in weed control, misuse can cause crop injury or failure to control weeds. This guide is an overview of factors that influence the fate, effectiveness-Applied Herbicides by Fabián D. Menalled, Extension Cropland Weeds Specialist, and William E. Dyer, Professor, Weed

  7. DNA Amounts in Two Samples of Angiosperm Weeds

    Microsoft Academic Search

    MICHAEL D. BENNETT; ILIA J. LEITCH; LYNDA HANSON

    1998-01-01

    Of the world's 250000 angiosperm species, only about 200 are recognized as important weeds. 4C nuclear DNA amounts were estimated for 39 such species. Success for many important weeds is suggested to reflect several traits known to correlate with low DNA C-value, so such weeds may have smaller DNA C-values than other species. Our work tests this hypothesis, comparing DNA

  8. Crop\\/weed competition studies in upland rice

    Microsoft Academic Search

    Govindra Singh; S. R. Yadav; D. Singh

    1987-01-01

    Critical period of crop\\/weed competition was studied in upland rice during monsoon season from 1981 to 1983. Echinochloa colonum, Seirpus grossus, Dactyloctenlum aegyptium, Cyperus rotundus, C. iria and Trianthema monogyna were the major weed species. Competition from weeds during the first 15 days after sowing (d.a.s.) had no significant effect on the grain yield of rice. Competition beyond 15 d.a.s.

  9. Optimal weeding treatments in upland rice: A crop competition experiment

    Microsoft Academic Search

    B. A. C. Legaspi Jr; C. P. Medina; J. C. Alagos; F. P. Lansigan

    1989-01-01

    A field experiment was performed to determine the effects of different times and frequencies of handweeding on grain yields in upland rice. Five weeding treatments were done. These treatments consisted of single weedings at 20 and 35 days after emergence (d.a.e.) and double weedings at 10 and 15 d.a.e., 20 and 35 d.a.e. and 30 and 45 d.a.e. Two controls

  10. Relationships between upland rice canopy characteristics and weed competitiveness

    Microsoft Academic Search

    M. Dingkuhn; D. E. Johnson; A. Sow; A. Y. Audebert

    1999-01-01

    Weed-competitive upland rices with an acceptable yield potential are needed for labor-limited systems in Africa, particularly where shortened fallow periods have increased weed pressure. Crosses between weed-competitive but low-yielding African rice, Oryza glaberrima, and improved Oryza sativa tropical-japonica rices, might reduce tradeoffs between competitiveness and yield potential. Parallel field studies under moist upland conditions were conducted during the 1996 and

  11. Weed selection by sheep grazing dryland lucerne

    Microsoft Academic Search

    E. Pérez; A. de Vega; I. Delgado; Y. Pueyo

    Diet selection by sheep grazing dryland lucerne with a high proportion of weeds was assessed in two consecutive years (2005\\/2006). The study was performed on 2.66 ha of pasture divided in two homogeneous paddocks subjected to a stocking rate of either 10 or 20 sheep\\/paddock, and grazed for 17 days. Before and after each grazing trial, an inventory was conducted

  12. ORIGINAL PAPER Weed seeds as nutritional resources for soil Ascomycota

    E-print Network

    Sims, Gerald K.

    -borne microorganisms. In this study, we investigated seeds of four common broadleaf weeds, velvetleaf (Abutilon theophrasti), woolly cupgrass (Eriochloa villosa), Pennsyl- vania smartweed (Polygonum pensylvanicum

  13. Ability of weeds to host the root lesion nematodes Pratylenchus neglectus and P. thornei I. Grass weeds

    Microsoft Academic Search

    Vivien A. Vanstone; Michelle H. Russ

    2001-01-01

    Nine grass weed species common to cropping rotations in southern Australia were assessed as hosts of the root lesion nematodes,\\u000a Pratylenchus neglectus (Rensch) Filipjev Schuurmans & Stekhoven and P. thornei Sher & Allen. Weeds were grown at 20°C and individual plants inoculated with 1000 P. neglectus or P. thornei. Weed species were classified as non-hosts, poor hosts or good hosts,

  14. Herbicide Resistant Weeds: Do Economic Thresholds Still Have a Role in Weed Management?

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Concern over the development of herbicide resistant weeds has prompted a closer look at the validity of using economic thresholds (ET) as a basis for making treatment decisions. In situations where herbicide resistance is suspected, growers are often advised to employ control measures to completely ...

  15. THE BIOLOGY OF CANADIAN WEEDS. 42. Stellaria media (L.\\ Yill.

    E-print Network

    Kenkel, Norm

    THE BIOLOGY OF CANADIAN WEEDS. 42. Stellaria media (L.\\ Yill. ROY TURKINGTON, NORMAN C. KENKEL. 1980. The biology of Canadian weeds. 42. Stellaria media (L.)Yill. Can. J. Plant Sci. 60: 98r-992. This paper provides a summary of biological data on Stellaria media (L.) Yill., commonly known as chickweed

  16. Potential components for weed management in organic vegetable production systems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Organic vegetable production relies on a variety of tactics for preventing losses to crop yield and quality that result from weed interference. These include field selection, long term field management, cultivation practices, mulching, and manual weeding to name a few. The concept of "herbicides" th...

  17. Weed occurrence on pavements in five North European towns

    Microsoft Academic Search

    B. Melander; N. Holst; A C GRUNDY; C. Kempenaar; M. M. Riemens; A. Verschwele; D. Hansson

    2009-01-01

    Weeds on pavements in urban areas are unwanted mainly because they cause an untidy appearance or sometimes structural damage. Glyphosate has been the principal weed control method for years, but policies in several European towns have changed to lower dependence on herbicides. Instead, less effective and more species-dependent non-chemical methods are used, but little is known about the pavement flora.

  18. Corn gluten meal: Weed control and yields for onions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    One weed control option for certified organic producers is corn gluten meal (CGM). Field research was conducted in southeast Oklahoma (Lane, OK) to determine the efficacy of CGM as an herbicide for use in transplanted onion production. The research involved 8 weed control treatments with 4 replicat...

  19. Use of cryptic species for biological control of weeds

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Classical biological control of weeds depends on the discovery and evaluation of species of arthropods that are highly host specific. The rarity of such species in nature limits our ability to find safe effective agents to control a continually increasing list of invasive alien weeds. However, sci...

  20. Weed suppression with grazing or atrazine during big bluestem establishment

    Microsoft Academic Search

    B. Keith Lawrence; Steven S. Waller; Lowell E. Moser; Bruce Anderson; Larry L. Larson

    1995-01-01

    Weed competition is a major factor causing warm-season grass seeding failures in rangeland and cropland. With a limited number of herbicides available for weed control, grazing may reduce competing vegetation in seedings and serve as an alternative to herbicides. Many immature needy forbs and grasses are palatable to cattle and contain high nutrient levels. Research was conducted (RCBD, 4 reps)

  1. Post-directed weed control in bell peppers

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Organic pepper (Capsicum annuum L.) producers need appropriate herbicides that can effectively provide post-emergent weed control. Research was conducted in southeast Oklahoma (Atoka County, Lane, OK) to determine the impact of a potential organic herbicide on weed control efficacy, crop injury, an...

  2. SOLARIA HELP PREDICT IN-CROP WEED DENSITIES

    Technology Transfer Automated Retrieval System (TEKTRAN)

    At locations in Argentina and USA, solaria (miniature, portable, plastic greenhouses or plastic sheets about 1 m**2) were placed on field soils in autumn or late winter in an attempt to predict summer annual weed densities. Initial emergence of summer annual weeds, covered by solaria commenced weeks...

  3. Working the Educational Soil and Pulling Up Weeds

    ERIC Educational Resources Information Center

    Riggins-Newby, Cheryl

    2005-01-01

    The job of an instructional leader, according to former Baltimore principal Deborah Wortham, is to be a gardener. School cultures left unattended, she says, sprout weeds that will eventually overwhelm the research-based programs, practices, and best efforts of teachers and administrators. The most aggressive and harmful educational weeds Wortham…

  4. 'Carolina' session: a major utilities program to manage aquatic weeds

    SciTech Connect

    Schiller, D.H.

    1984-06-01

    Carolina Power and Light Company has recently experienced aquatic weed problems in two of its impoundments. These problems have impacted power plant operations, water quality, and recreational activities. The Company is actively pursuing a program to deal with these weed problems through education, research, monitoring, and control activities.

  5. Weed manipulation for insect pest management in corn

    NASA Astrophysics Data System (ADS)

    Altieri, M. A.; Whitcomb, W. H.

    1980-11-01

    Populations of insect pests and associated predaceous arthropods were sampled by direct observation and other relative methods in simple and diversified corn habitats at two sites in north Florida during 1978 and 1979. Through various cultural manipulations, characteristic weed communities were established selectively in alternate rows within corn plots. Fall armyworm ( Spodoptera frugiperda J. E. Smith) incidence was consistently higher in the weed-free habitats than in the corn habitats containing natural weed complexes or selected weed associations. Corn earworm ( Heliothis zea Boddie) damage was similar in all weed-free and weedy treatments, suggesting that this insect is not affected greatly by weed diversity. Only the diversification of corn with a strip of soybean significantly reduced corn earworm damage. In one site, distance between plots was reduced. Because predators moved freely between habitats, it was difficult to identify between-treatment differences in the composition of predator communities. In the other site, increased distances between plots minimized such migrations, resulting in greater population densities and diversity of common foliage insect predators in the weed-manipulated corn systems than in the weed-free plots. Trophic relationships in the weedy habitats were more complex than food webs in monocultures. Predator diversity (measured as mean number of species per area) and predator density was higher in com plots surrounded by mature, complex vegetation than at those surrounded by annual crops. This suggests that diverse adjacent areas to crops provide refuge for predators, thus acting as colonization sources.

  6. Molecular Biology and Genomics: New Tools for Weed Science

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Certain plant species are particularly well adapted to environments disturbed by humans. Often such species are invasive and problematic, and thus are classified as weeds. Despite our best efforts to control weeds, they continue to interfere with crop production. Clearly there is much to learn about...

  7. Weed science research and funding: a call to action

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Weed science has contributed much to agriculture, forestry and natural resource management over its history. However, if it is to remain relevant as a scientific discipline, it is long past time for weed scientists to take a step outside the “herbicide efficacy box” and address system-level issues i...

  8. Evaluation of corn gluten meal for weed control in cowpea

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Current weed control practices for cowpea production typically involve use of synthetic herbicides. Increasing interest in organic crop production creates a need for alternative weed control techniques that are consistent with requirements of the USDA National Organic Program. Corn gluten meal (CG...

  9. Corn gluten meal for weed control in cowpea

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Cowpea, a major crop in Oklahoma, is produced for the fresh market and canning industry. Synthetic preemergence and postemergence herbicides are the primary weed control method in conventional (non-organic) production systems. Organic weed control in organic cowpea production includes obstacles wh...

  10. Weeds of the Midwestern United States and Central Canada

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The book, Weeds of the Central United States and Canada, includes 356 of the most common and/or troublesome weeds of agricultural and natural areas found within the central region of the United States and Canada. The books includes an introduction, a key to plant families contained in the book, glo...

  11. Allelopathic Interactions and Allelochemicals: New Possibilities for Sustainable Weed Management

    Microsoft Academic Search

    H. P. Singh; Daizy R. Batish; R. K. Kohli

    2003-01-01

    Weeds are known to cause enormous losses due to their interference in agroecosystems. Because of environmental and human health concerns, worldwide efforts are being made to reduce the heavy reliance on synthetic herbicides that are used to control weeds. In this regard the phenomenon of allelopathy, which is expressed through the release of chemicals by a plant, has been suggested

  12. Weed Suppression by Seven Clover Species

    SciTech Connect

    Ross, Shirley M.; King, Jane R.; Izaurralde, R Cesar C.; O'Donovan, John T.

    2001-01-01

    Used as cover crops, clover species may differ in their ability to suppress weed growth. Field trials were conducted in Alberta, Canada to measure the growth of brown mustard [Brassica juncea (L.) Czern.], in mowed and nonmowed production, as influenced by alsike (Trifolium hybridum L.), balansa [T. michelianum Savi var. balansae (Boiss.) Azn.], berseem (T. alexandrinum L.), crimson [T. incarnatum (Boiss.) Azn.], berseem (T. alexandrinum L.), crimson (T. incarnatum L.), Persian (T. resupinatum L.), red (T. pratense L.), and white Dutch (T. repens L.) clover and fall rye (Secale cereale L.). In 1997, clovers reduced mustard biomass in nonmowed treatments by 29% on a high- fertility soil (Typic Cryoboroll) at Edmonton and by 57% on a low- fertility soil (Typic Cryoboralf) at Breton. At Edmonton, nonmowed mustard biomass was reduced by alsike and berseem clover in 1996 and by alsike, balansa, berseem, and crimson clover in 1997. At Breton, all seven clover species suppressed weed biomass. A negative correlation was noted among clover and mustard biomass at Edmonton but not at Breton. The effects of mowing varied with location, timing, and species. Mowing was beneficial to crop/weed proportion at Edmonton but not at Breton. Mowing at early flowering of mustard large-seeded legumes and sweetclover (Melilotus offici) produced greater benefit than mowing at late flowering. With early mowing, all clover species suppressed mustard growth at Edmonton. Clovers reduced mustard regrowth (g plant21 ) and the number of mustard plants producing regrowth. The characteristics of berseem clover (upright growth, long stems, high biomass, and late flowering) would support its use as a cover crop or forage in north-central Alberta.

  13. Weed hosts of Verticillium dahliae in cotton fields in Turkey and characterization of V. dahliae isolates from weeds

    Microsoft Academic Search

    Ayhan Yildiz; M. Nedim Do?an; Özhan Boz; Seher Benlio?lu

    2009-01-01

    A weed survey conducted in 2004 and 2005 in Aydin province of Turkey showed that Solanum nigrum, Xanthium strumarium, Amaranthus retroflexus, Portulaca oleracea, Sonchus oleraceus and Datura stramonium were the most prevalent weeds in the cotton fields exhibiting Verticillium wilt. Verticillium dahliae Kleb. was recovered from A. retroflexus and X. strumarium in those cotton fields. This is the first report

  14. Long-term experiments with reduced tillage in spring cereals. I. Effects on weed flora, weed seedbank and grain yield

    Microsoft Academic Search

    K. Semb Tørresen; R. Skuterud; H. J. Tandsæther; M. Bredesen Hagemo

    2003-01-01

    In four field experiments lasting from autumn 1993 to 2000, perennial weeds and overwintering weed species increased with reduced tillage compared to ploughing in autumn or spring. Abundant species were Cirsium arvense, Elymus repens, Matricaria perforata, Poa annua and Stellaria media. With no-tillage, grassland perennials were detected. Volunteer oats increased in plots without ploughing. A combination of glyphosate and post-emergence

  15. Weed populations and agronomic practices at wheat farms on the Hanang plains in Tanzania

    Microsoft Academic Search

    J. R. Moyer; Z. J. Owenya; S. P. Kibuwa

    1989-01-01

    Weed species and densities of weeds present on the wheat farms at the Hanang plains in northern Tanzania were surveyed just before wheat harvest in May, 1986. The dominant weed was Setaria spp. mainly, Setaria verticillata (L.) Beauv., which occurred at an average density of 58 shoots\\/m. Additional weed species which occurred at average densities of greater than 1 plant\\/m

  16. (9/12) Pistachio Weed Survey Form 1 Download at www.ipm.ucdavis.edu/FORMS

    E-print Network

    Ishida, Yuko

    (9/12) Pistachio Weed Survey Form 1 Download at www.ipm.ucdavis.edu/FORMS www.ipm.ucdavis.edu Pistachio Weed Survey Form Supplement to UC IPM Pest Management Guidelines Grower or Orchard ___________________________________________________ _____________________________________________________________________________________________ Remember, weeds in tree rows are unwanted, but weeds in row middles can be beneficial as long as they do

  17. South Carolina Pest Management Handbook for Field Crops -2014 WEED CONTROL IN PEANUT

    E-print Network

    Duchowski, Andrew T.

    South Carolina Pest Management Handbook for Field Crops - 2014 163 WEED CONTROL IN PEANUT Mike Marshall, Extension Weed Specialist Preplant/Burndown Herbicides for Weed Management in Peanut Herbicide time before planting. For best results, apply when weeds are less than 4 inches tall (less than 3 inch

  18. South Carolina Pest Management Handbook for Field Crops -2014 WEED CONTROL IN SOYBEAN

    E-print Network

    Duchowski, Andrew T.

    South Carolina Pest Management Handbook for Field Crops - 2014 215 WEED CONTROL IN SOYBEAN Mike Marshall, Extension Weed Specialist Preplant/Burndown Herbicides for Weed Management in Soybean Herbicide time before planting. For best results, apply when weeds are less than 4 inches tall (less than 3 inch

  19. South Carolina Pest Management Handbook for Field Crops -2014 WEED CONTROL IN COTTON

    E-print Network

    Duchowski, Andrew T.

    South Carolina Pest Management Handbook for Field Crops - 2014 70 WEED CONTROL IN COTTON Mike Marshall, Extension Weed Specialist Preplant Burndown Herbicides for Weed Management in Cotton Herbicide any time prior to planting. For best results, apply to weeds that are less than 4 inches tall (less

  20. South Carolina Pest Management Handbook for Field Crops -2013 WEED CONTROL IN TOBACCO

    E-print Network

    Stuart, Steven J.

    South Carolina Pest Management Handbook for Field Crops - 2013 257 WEED CONTROL IN TOBACCO Mike Marshall, Extension Weed Specialist Preplant (Incorporated) Herbicides for Weed Management in Tobacco by shallow disking. Controls pigweed, ragweed and other broadleaf weeds. Use the higher rate for fields

  1. Noxious Weed Monitoring at the U.S. Air Force Academy-Year 3 Results

    E-print Network

    Noxious Weed Monitoring at the U.S. Air Force Academy- Year 3 Results March 21, 2008 Prepared For............................................................................................................. 3 HISTORY OF WEED MAPPING AND MONITORING AT THE ACADEMY................................ 3 WEED................................................................................. 45 NATURAL RESOURCE-BASED NOXIOUS WEED MONITORING ........................................ 46 SUMMARY

  2. LRES 443 -WEED ECOLOGY & MANAGEMENT Instructor: Dr. Bruce Maxwell TA: Melissa Bridges

    E-print Network

    Maxwell, Bruce D.

    1 LRES 443 - WEED ECOLOGY & MANAGEMENT Instructor: Dr. Bruce Maxwell TA: Melissa Bridges Professor and understanding of the principles of weed science. 2. To develop an appreciation for adaptations that allow weeds and concepts associated with plant population and community ecology. 4. To develop an understanding of how weed

  3. Potential of 3D-weed density maps in Precision Matthias Backes and Lutz Plumer

    E-print Network

    Behnke, Sven

    Potential of 3D-weed density maps in Precision Farming Matthias Backes and Lutz Pl¨umer Institute;pluemer)@ikg.uni-bonn.de WWW: http://www.ikg.uni-bonn.de Abstract. The exact knowledge about the spatial distribution of weeds weed maps derived from spatial sampling continuous threshold-based contours of weed patches or areas

  4. South Carolina Pest Management Handbook for Field Crops -2013 WEED CONTROL IN SOYBEAN

    E-print Network

    Stuart, Steven J.

    South Carolina Pest Management Handbook for Field Crops - 2013 205 WEED CONTROL IN SOYBEAN Mike Marshall, Extension Weed Specialist Preplant/Burndown Herbicides for Weed Management in Soybean Herbicide time before planting. For best results, apply when weeds are less than 4 inches tall (less than 3 inch

  5. Weed leaf recognition in complex natural scenes by model-guided edge Benoit De Mezzo1

    E-print Network

    Paris-Sud XI, Université de

    Weed leaf recognition in complex natural scenes by model-guided edge pairing Benoit De Mezzo1.demezzo@cemagref.fr ; gilles.rabatel@cemagref.fr ; fiorio@lirmm.fr Abstract New weeding strategies for pesticide reduction rely on the spatial distribution and characterisation of weed populations. For this purpose, weed identification can

  6. South Carolina Pest Management Handbook for Field Crops -2013 WEED CONTRL IN FIELD CORN

    E-print Network

    Stuart, Steven J.

    South Carolina Pest Management Handbook for Field Crops - 2013 17 WEED CONTRL IN FIELD CORN Mike Marshall, Extension Weed Specialist Preplant/Burndown Herbicides for Weed Management in Corn solution for weeds 3 inches or less in height. BALANCE FLEXX may be tank mixed with PARAQUAT, GLYPHOSATE

  7. South Carolina Pest Management Handbook for Field Crops -2013 WEED CONTROL IN PEANUT

    E-print Network

    Stuart, Steven J.

    South Carolina Pest Management Handbook for Field Crops - 2013 152 WEED CONTROL IN PEANUT Mike Marshall, Extension Weed Specialist Preplant/Burndown Herbicides for Weed Management in Peanut Herbicide time before planting. For best results, apply when weeds are less than 4 inches tall (less than 3 inch

  8. Effects of artificial shading and weed mowing in reforestation of Mediterranean abandoned cropland with contrasting

    E-print Network

    Espigares, Tíscar

    Effects of artificial shading and weed mowing in reforestation of Mediterranean abandoned cropland, and weeds are strong competitors for resources, particularly water. We conducted a 3-year experiment of full-light versus artificial shading and weed presence versus weed mowing. We measured seedling

  9. Horticultural & Forest crops 2014 Grapes: Weed Control in Vineyards 3-19

    E-print Network

    Liskiewicz, Maciej

    Horticultural & Forest crops 2014 Grapes: Weed Control in Vineyards 3-19 Weed Control in Vineyards Jeffrey F. Derr, Extension Weed Scientist, Hampton Roads AREC Table 3.5 - Herbicides Labeled for Use and postemergence herbicides can be made to control existing vegetation and control weeds germinating from seed

  10. South Carolina Pest Management Handbook for Field Crops -2013 WEED CONTROL IN GRAIN SORGHUM

    E-print Network

    Stuart, Steven J.

    South Carolina Pest Management Handbook for Field Crops - 2013 137 WEED CONTROL IN GRAIN SORGHUM Mike Marshall, Extension Weed Specialist Preplant/Burndown Herbicides for Weed Management in Grain and cutleaf evening primrose than GLYPHOSATE. Add NIS at 1 qt/100 gal of spray mix. Weed and Cover Crop

  11. South Carolina Pest Management Handbook for Field Crops -2014 WEED CONTROL IN TOBACCO

    E-print Network

    Duchowski, Andrew T.

    South Carolina Pest Management Handbook for Field Crops - 2014 270 WEED CONTROL IN TOBACCO Mike Marshall, Extension Weed Specialist Preplant (Incorporated) Herbicides for Weed Management in Tobacco by shallow disking. Controls pigweed, ragweed and other broadleaf weeds. Use the higher rate for fields

  12. Monthly Highlights from Rutgers New Jersey Agricultural Experiment Station January 2009 Weed Control Strategy Differences in

    E-print Network

    Goodman, Robert M.

    Monthly Highlights from Rutgers New Jersey Agricultural Experiment Station January 2009 Weed in Weed Science and Jack Rabin, Associate Director - Farm Programs Continued on page 2 Let no weeds go to seeds. Farmers wanting to control weeds with non-chemical herbicide alternatives should

  13. Weed Control 2008 Burley ToBacco ProducTion Guide

    E-print Network

    Liskiewicz, Maciej

    Weed Control 2008 Burley ToBacco ProducTion Guide WEED CONTROL IN BURLEy TOBACCO Charles S. Johnson, Extension Plant Pathologist, Tobacco Good weed control uses crop rotation, early root destruction on the first cultivation for early-season weed control. Some herbicides may also be applied to the row mid- dle

  14. South Carolina Pest Management Handbook for Field Crops -2013 WEED CONTROL IN COTTON

    E-print Network

    Stuart, Steven J.

    South Carolina Pest Management Handbook for Field Crops - 2013 63 WEED CONTROL IN COTTON Mike Marshall, Extension Weed Specialist Preplant Burndown Herbicides for Weed Management in Cotton Herbicide any time prior to planting. For best results, apply to weeds that are less than 4 inches tall (less

  15. The system management approach of biological weed control: Some theoretical considerations and aspects of application

    Microsoft Academic Search

    J. Frantzen; N. D. Paul; H. Müller-schärer

    2001-01-01

    Theoretical considerations behind the system management approach of biological weed control are presented. These include, a part describing and explaining the effects of parasitic fungi on crop – weed competition, a part describing and explaining the epidemic spread of parasitic fungi on weeds, and a part relating crop – weed competition at the population level to epidemics. The theoretical framework

  16. Combinations of Microbial and Insect Biocontrol Agents for Management of Weed Seeds

    Microsoft Academic Search

    R. J. KREMER

    Important roles for biotic agents in integrated weed management include preventing seed production and weed emergence from the seed bank. Seed-attacking microorganisms have been described for a limited number of economically important weeds and serve as examples illustrating the potential for reducing weed seed production. Innundative releas- es of seed-feeding insects have also successfully reduced viable seeds produced by spe-

  17. Allelopathic influence of Sorghum bicolor on weeds during germination and early development of seedlings

    Microsoft Academic Search

    Oksana Panasiuk; Donald D. Bills; Gerald R. Leather

    1986-01-01

    The allelopathic interaction between sorghum [Sorghum bicolor (L.) Moench] and 10 species of grass and broadleaf weeds was investigated. Germination of weed seeds was slightly inhibited or stimulated, depending on species, when incubated in closed Petri dishes with germinating sorghum. Subsequent radicle and hypocotyl or coleoptile elongation of weeds was significantly inhibited by the germinating sorghum. For weeds interplanted with

  18. Use of weeds as traditional vegetables in Shurugwi District, Zimbabwe

    PubMed Central

    2013-01-01

    Background Most agricultural weeds are usually regarded as undesirable and targeted for eradication. However, weeds are useful to human beings as food and traditional medicines. Few studies have been done to document the uses of weeds as traditional vegetables. This study was therefore, done to document indigenous knowledge related to the diversity and use of agricultural weeds as traditional vegetables in Shurugwi District, Zimbabwe, emphasizing their role in food security and livelihoods of the local people. Materials and methods Semi-structured interviews, observation and guided field walks with 147 participants were employed between December 2011 and January 2012 to obtain ethnobotanical data on the use of edible weeds as traditional vegetables. Based on ethnobotanical information provided by the participants, botanical specimens were collected, numbered, pressed and dried for identification. Results A total of 21 edible weeds belonging to 11 families and 15 genera, mostly from Amaranthaceae (19%), Asteraceae and Tiliaceae (14.3%), Capparaceae, Cucurbitaceae and Solanaceae (9.5% each) were identified. Of the documented edible weeds, 52.4% are indigenous while 47.6% are exotic to Zimbabwe; either semi-cultivated or growing naturally as agricultural weeds in farmlands, fallow land and home gardens. Among the main uses of edible weeds were leafy vegetables (81%), followed by edible fruits (19%), edible corms (9.5%), edible flowers and seeds (4.8% each). The most important edible weeds were Cleome gynandra, cited by 93.9% of the participants, Cucumis metuliferus (90.5%), Cucumis anguria (87.8%), Corchorus tridens (50.3%) and Amaranthus hybridus (39.5%). All edible weeds were available during rainy and harvest period with Cleome gynandra, Corchorus tridens, Cucumis anguria, Cucumis metuliferus and Moringa oleifera also available during the dry season, enabling households to obtain food outputs in different times of the year. The importance of edible weeds for local livelihoods was ubiquitously perceived, with all participants reporting their contribution towards food security and nutrition. Conclusion The present study confirm findings from similar studies conducted elsewhere that rural households engage in harvesting of wild edible vegetables and other non-timber forest products (NTFPs) as a survival strategy. Based on their potential nutritional and medicinal value, edible weeds could contribute in a major way to food security, basic primary health care and balanced diets of rural households and possibly urban households as well. PMID:23962298

  19. Wallowa Canyonlands Weed Partnership : Completion Report November 19, 2009

    SciTech Connect

    Porter, Mark C.; Ketchum, Sarah

    2008-12-30

    Noxious weeds threaten fish and wildlife habitat by contributing to increased sedimentation rates, diminishing riparian structure and function, and reducing forage quality and quantity. Wallowa Resources Wallowa Canyonlands Partnership (WCP) protects the unique ecological and economic values of the Hells Canyon grasslands along lower Joseph Creek, the lower Grande Ronde and Imnaha Rivers from invasion and degradation by noxious weeds using Integrated Weed Management techniques. Objectives of this grant were to inventory and map high priority weeds, coordinate treatment of those weeds, release and monitor bio-control agents, educate the public as to the dangers of noxious weeds and how to deal with them, and restore lands to productive plant communities after treatment. With collaborative help from partners, WCP inventoried {approx} 215,000 upland acres and 52.2 miles of riparian habitat, released bio-controls at 23 sites, and educated the public through posters, weed profiles, newspaper articles, and radio advertisements. Additionally, WCP used other sources of funding to finance the treatment of 1,802 acres during the course of this grant.

  20. The Southern Weed Science Society Weed Contest was held on August 1, 2012 in Fayetteville, AR. This event is an educational experience for undergraduate and graduate students in Southern Universities to

    E-print Network

    Tennessee, University of

    The Southern Weed Science Society Weed Contest was held on August 1, 2012 in Fayetteville, AR to broaden their applied skills in Weed Science. The contest consists of 5 parts which are weed identification, applicator calibration, herbicide identification by the response of various crops and weeds

  1. Timing and Frequency of Between-Row Mowing and Band-Applied Herbicide for Annual Weed Control in Soybean

    Microsoft Academic Search

    William W. Donald

    2000-01-01

    did not consistently control weeds from year to year, two or more BR mowings consistently controlled weeds Alternative ways are needed to control weeds in field crops that in this BR-mowing weed management system (Donald, reduce or prevent both herbicide contamination of surface and ground water and soil erosion. A new weed management system, which con- 2000b). It is not

  2. Control of aquatic weeds through pollutant reduction and weed utilization: a weed management approach in the lower Kafue River of Zambia

    NASA Astrophysics Data System (ADS)

    Sinkala, Thomson; Mwase, Enala T.; Mwala, Mick

    The aquatic weed situation in the Kafue River in Zambia continues to be a major challenge to the sustainable utilization of the water resources of the river. The general methods for managing the weeds, especially the water hyacinth, include use of bio-agents, chemicals, mechanical and physical approaches. These have had very little impact. This paper reports on a project that is investigating weed management strategies which involve use of cleaner production (CP) approach and the utilization of the weed for economic purposes. In addition, the ecological implications of these methods are being assessed. Effluent assessments indicated that apart from nitrates and phosphates, other effluent parameters met the Environmental Council of Zambia standards. Results further show that all the 24 areas surveyed for CP have uncontrolled socio-economic activities which generate both point and non-point sources of pollution that enter the water bodies. To minimize pollution, efforts include devising policy and technical strategies with the involvement of the affected riparian community. Production of mushroom by the communities using the water hyacinth substrate has been demonstrated. Up to 2.1 kg of mushroom was harvested from a single flush over a period of 4-5 weeks. Vegetables grown on soils treated with water hyacinth manure performed better than those grown using commercial fertiliser. The economics of the production are however, yet to be confirmed. If weed usage is proven economically and ecologically viable, the riverine community is envisaged to play a big role in aquatic weed management. High numbers of invertebrates known to be sensitive to pollution have been recorded in the weed-infested Kafue River implying that the water is of “good” quality for these aquatic invertebrates. This observed quality of water may be due to water hyacinth playing a role by sieving pollutants from the river.

  3. Crop performance and weed suppression by weed-suppressive rice cultivars in furrow- and flood-irrigated systems under reduced herbicide inputs

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Weed control in rice is challenging, particularly in light of increased resistance to herbicides in weed populations and diminishing availability of irrigation water. Certain indica rice cultivars can produce high yields and suppress weeds in conventional flood-irrigated, drill-seeded systems in the...

  4. Mapping invasive weeds and their control with spatial information technologies

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We discuss applications of airborne multispectral digital imaging systems, imaging processing techniques, global positioning systems (GPS), and geographic information systems (GIS) for mapping the invasive weeds giant salvinia (Salvinia molesta) and Brazilian pepper (Schinus terebinthifolius) and fo...

  5. Integrated Systems of Weed Management in Organic 'Vidalia' Onion

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Trials were conducted in southeastern Georgia to develop integrated systems of weed management in organic Vidalia® onion. Treatments were a factorial arrangement of summer solarization, cultivation, and herbicides appropriate for use in certified organic production systems. Plots were solarized wi...

  6. DEVELOPING WEED SUPPRESSIVE SOILS THROUGH IMPROVED SOIL QUALITY MANAGEMENT

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Sustainable agriculture is based in part on efficient management of soil microorganisms for improving soil quality. However, identification of biological indicators of soil quality for predicting weed suppression in soils has received little attention. We investigated differences in soil microbial ...

  7. Appearance of Herbicide Resistance in a Weed Population

    NSDL National Science Digital Library

    Through the repeated use of the same herbicide, weed populations can consist of susceptible (S)-biotypes that are controlled and herbicide resistant (R)-biotypes that are left behind to produce and return seed with the resistance characteristic back into the soil. This lesson will highlight the population dynamics of a mixed weed population, containing S- and R-biotypes, and compare and contrast the rate at which herbicide resistant weeds appear in a population under a diversity of selection pressures. This lesson will highlight the population dynamics of a mixed (herbicide susceptible and resistant biotype) weed population, and compare and contrast the rate of appearance of herbicide resistance in a mixed population under a diversity of selection pressures.

  8. Weed Control Sprayers: Calibration and Maintenance. Special Circular 81.

    ERIC Educational Resources Information Center

    Myers, Arthur L.

    This manual covers aspects of calibration and maintenance of weed control sprayers including variables affecting application rate, the pre-calibration check, calculations, band spraying, nozzle tip selection, agitation, and cleaning. (BB)

  9. Protecting the Environment Using Integrated Weed Management in Lawns 

    E-print Network

    Ketchersid, Mary; Baumann, Paul A.

    2008-03-27

    Integrated Pest Management (IPM) can be used to control weeds, keep lawns healthy and protect the environment. This publication explains the steps to take in an IPM program and the importance of calibrating equipment and making proper calculations...

  10. The biology of habitat dominance; can microbes behave as weeds?

    PubMed

    Cray, Jonathan A; Bell, Andrew N W; Bhaganna, Prashanth; Mswaka, Allen Y; Timson, David J; Hallsworth, John E

    2013-09-01

    Competition between microbial species is a product of, yet can lead to a reduction in, the microbial diversity of specific habitats. Microbial habitats can resemble ecological battlefields where microbial cells struggle to dominate and/or annihilate each other and we explore the hypothesis that (like plant weeds) some microbes are genetically hard-wired to behave in a vigorous and ecologically aggressive manner. These 'microbial weeds' are able to dominate the communities that develop in fertile but uncolonized--or at least partially vacant--habitats via traits enabling them to out-grow competitors; robust tolerances to habitat-relevant stress parameters and highly efficient energy-generation systems; avoidance of or resistance to viral infection, predation and grazers; potent antimicrobial systems; and exceptional abilities to sequester and store resources. In addition, those associated with nutritionally complex habitats are extraordinarily versatile in their utilization of diverse substrates. Weed species typically deploy multiple types of antimicrobial including toxins; volatile organic compounds that act as either hydrophobic or highly chaotropic stressors; biosurfactants; organic acids; and moderately chaotropic solutes that are produced in bulk quantities (e.g. acetone, ethanol). Whereas ability to dominate communities is habitat-specific we suggest that some microbial species are archetypal weeds including generalists such as: Pichia anomala, Acinetobacter spp. and Pseudomonas putida; specialists such as Dunaliella salina, Saccharomyces cerevisiae, Lactobacillus spp. and other lactic acid bacteria; freshwater autotrophs Gonyostomum semen and Microcystis aeruginosa; obligate anaerobes such as Clostridium acetobutylicum; facultative pathogens such as Rhodotorula mucilaginosa, Pantoea ananatis and Pseudomonas aeruginosa; and other extremotolerant and extremophilic microbes such as Aspergillus spp., Salinibacter ruber and Haloquadratum walsbyi. Some microbes, such as Escherichia coli, Mycobacterium smegmatis and Pseudoxylaria spp., exhibit characteristics of both weed and non-weed species. We propose that the concept of nonweeds represents a 'dustbin' group that includes species such as Synodropsis spp., Polypaecilum pisce, Metschnikowia orientalis, Salmonella spp., and Caulobacter crescentus. We show that microbial weeds are conceptually distinct from plant weeds, microbial copiotrophs, r-strategists, and other ecophysiological groups of microorganism. Microbial weed species are unlikely to emerge from stationary-phase or other types of closed communities; it is open habitats that select for weed phenotypes. Specific characteristics that are common to diverse types of open habitat are identified, and implications of weed biology and open-habitat ecology are discussed in the context of further studies needed in the fields of environmental and applied microbiology. PMID:23336673

  11. The biology of habitat dominance; can microbes behave as weeds?

    PubMed Central

    Cray, Jonathan A; Bell, Andrew N W; Bhaganna, Prashanth; Mswaka, Allen Y; Timson, David J; Hallsworth, John E

    2013-01-01

    Summary Competition between microbial species is a product of, yet can lead to a reduction in, the microbial diversity of specific habitats. Microbial habitats can resemble ecological battlefields where microbial cells struggle to dominate and/or annihilate each other and we explore the hypothesis that (like plant weeds) some microbes are genetically hard-wired to behave in a vigorous and ecologically aggressive manner. These ‘microbial weeds’ are able to dominate the communities that develop in fertile but uncolonized – or at least partially vacant – habitats via traits enabling them to out-grow competitors; robust tolerances to habitat-relevant stress parameters and highly efficient energy-generation systems; avoidance of or resistance to viral infection, predation and grazers; potent antimicrobial systems; and exceptional abilities to sequester and store resources. In addition, those associated with nutritionally complex habitats are extraordinarily versatile in their utilization of diverse substrates. Weed species typically deploy multiple types of antimicrobial including toxins; volatile organic compounds that act as either hydrophobic or highly chaotropic stressors; biosurfactants; organic acids; and moderately chaotropic solutes that are produced in bulk quantities (e.g. acetone, ethanol). Whereas ability to dominate communities is habitat-specific we suggest that some microbial species are archetypal weeds including generalists such as: Pichia anomala, Acinetobacter spp. and Pseudomonas putida; specialists such as Dunaliella salina, Saccharomyces cerevisiae, Lactobacillus spp. and other lactic acid bacteria; freshwater autotrophs Gonyostomum semen and Microcystis aeruginosa; obligate anaerobes such as Clostridium acetobutylicum; facultative pathogens such as Rhodotorula mucilaginosa, Pantoea ananatis and Pseudomonas aeruginosa; and other extremotolerant and extremophilic microbes such as Aspergillus spp., Salinibacter ruber and Haloquadratum walsbyi. Some microbes, such as Escherichia coli, Mycobacterium smegmatis and Pseudoxylaria spp., exhibit characteristics of both weed and non-weed species. We propose that the concept of nonweeds represents a ‘dustbin’ group that includes species such as Synodropsis spp., Polypaecilum pisce, Metschnikowia orientalis, Salmonella spp., and Caulobacter crescentus. We show that microbial weeds are conceptually distinct from plant weeds, microbial copiotrophs, r-strategists, and other ecophysiological groups of microorganism. Microbial weed species are unlikely to emerge from stationary-phase or other types of closed communities; it is open habitats that select for weed phenotypes. Specific characteristics that are common to diverse types of open habitat are identified, and implications of weed biology and open-habitat ecology are discussed in the context of further studies needed in the fields of environmental and applied microbiology. PMID:23336673

  12. Locoine, the Poisonous Principle of Loco Weed, Astragalus earlei.

    E-print Network

    Fraps, G. S. (George Stronach); Carlyle, E. C. (Elmer Cardinal)

    1936-01-01

    TEXAS AGRICULTURAL EXPERIMENT STATION A. B. CONMER, DIRECTOR COLLEGE STATIONp BRAZOS COUNTY* TEXAS RULLETIN NO. 53 7 NOVEMBER, 1936 DIVISION OF CHEMISTRY LOCQINE, THE POISONOUS PRINCIPLE OF LOCO WEED Astragalus Earlei LTBRARY 1(\\flc... weed Astragalus *lei. The toxic principle has been given the name locoine. has been isolated by a long series of chemical separations, :h separation being tested by feeding to cats. It is a strong se, very soluble in water a.nd alcohol, but only...

  13. Index Selection for Weed Suppressive Ability in Soybean

    Microsoft Academic Search

    J.-L. Jannink; J. H. Orf; N. R. Jordan; R. G. Shaw

    2000-01-01

    glycine), and trifluralin (a,a,a-trifluoro-2,6-Dinitro-N, N-dipropyl-p-toluidine) are prone to leaving the site of The economic and environmental costs of weed management in application through surface runoff, potentially adversely soybean (Glycine max (L.) Merr.) have led to interest in developing weed suppressive soybean varieties to enhance traditional herbicide affecting water quality (USDA\\/NRCS, 1998). Besides and tillage-based approaches. We evaluated 104 inbred progeny

  14. Weed control in a pigeon pea–wheat cropping system

    Microsoft Academic Search

    James E. Bidlack; Andy Middick; Delmar Shantz; Charles T. MacKown; Robert D. Williams; Srinivas C. Rao

    2006-01-01

    Pigeon pea (Cajanus cajan (L.) Millsp.) seedlings compete poorly against the rapid growth of warm-season annual weeds. Weed control is required before this heat and drought-tolerant legume can be reliably grown in the U.S. southern Great Plains as a potential source of livestock hay between annual plantings of winter wheat (Triticum aestivum L.). Currently, no herbicides are labeled for use

  15. Weed control in glyphosate-tolerant maize in Europe.

    PubMed

    Dewar, Alan M

    2009-10-01

    Maize growing in the EU27 increased to over 13 million ha in 2007, most of which (>80%) was grown in just eight countries (France, Romania, Germany, Hungary, Italy, Poland, Spain and Bulgaria). The number of herbicides used to control the wide spectrum of weeds occurring in all these countries is likely to decline in the future as each current active ingredient is reassessed for toxicological and environmental safety under Directive 91/414/EEC. Glyphosate has already been approved under this directive. Glyphosate, applied alone or in combination with currently available residual herbicides to genetically modified varieties tolerant to glyphosate, can provide a viable, flexible and profitable alternative to conventional weed control programmes. Glyphosate usage with glyphosate-tolerant varieties also provides an environmentally sustainable weed control option as long as sufficient diversity of weed management options (crop rotation, chemical diversity, multiple cultural and mechanical practices, buffer strips) is maintained within the farm management system. Appropriate product stewardship measures will be required to maximise the long-term overall benefits of the glyphosate-based system. Specifically, care will need to be taken to manage potential weed shifts to more difficult-to-control species and to reduce the risk of selection for glyphosate-resistant weeds. PMID:19557724

  16. Robust crop and weed segmentation under uncontrolled outdoor illumination.

    PubMed

    Jeon, Hong Y; Tian, Lei F; Zhu, Heping

    2011-01-01

    An image processing algorithm for detecting individual weeds was developed and evaluated. Weed detection processes included were normalized excessive green conversion, statistical threshold value estimation, adaptive image segmentation, median filter, morphological feature calculation and Artificial Neural Network (ANN). The developed algorithm was validated for its ability to identify and detect weeds and crop plants under uncontrolled outdoor illuminations. A machine vision implementing field robot captured field images under outdoor illuminations and the image processing algorithm automatically processed them without manual adjustment. The errors of the algorithm, when processing 666 field images, ranged from 2.1 to 2.9%. The ANN correctly detected 72.6% of crop plants from the identified plants, and considered the rest as weeds. However, the ANN identification rates for crop plants were improved up to 95.1% by addressing the error sources in the algorithm. The developed weed detection and image processing algorithm provides a novel method to identify plants against soil background under the uncontrolled outdoor illuminations, and to differentiate weeds from crop plants. Thus, the proposed new machine vision and processing algorithm may be useful for outdoor applications including plant specific direct applications (PSDA). PMID:22163954

  17. Robust Crop and Weed Segmentation under Uncontrolled Outdoor Illumination

    PubMed Central

    Jeon, Hong Y.; Tian, Lei F.; Zhu, Heping

    2011-01-01

    An image processing algorithm for detecting individual weeds was developed and evaluated. Weed detection processes included were normalized excessive green conversion, statistical threshold value estimation, adaptive image segmentation, median filter, morphological feature calculation and Artificial Neural Network (ANN). The developed algorithm was validated for its ability to identify and detect weeds and crop plants under uncontrolled outdoor illuminations. A machine vision implementing field robot captured field images under outdoor illuminations and the image processing algorithm automatically processed them without manual adjustment. The errors of the algorithm, when processing 666 field images, ranged from 2.1 to 2.9%. The ANN correctly detected 72.6% of crop plants from the identified plants, and considered the rest as weeds. However, the ANN identification rates for crop plants were improved up to 95.1% by addressing the error sources in the algorithm. The developed weed detection and image processing algorithm provides a novel method to identify plants against soil background under the uncontrolled outdoor illuminations, and to differentiate weeds from crop plants. Thus, the proposed new machine vision and processing algorithm may be useful for outdoor applications including plant specific direct applications (PSDA). PMID:22163954

  18. Division of Agricultural Sciences and Natural Resources Oklahoma State University Weed Control in Christmas tree plantations is one of

    E-print Network

    Balasundaram, Balabhaskar "Baski"

    Division of Agricultural Sciences and Natural Resources · Oklahoma State University Weed Control.Weedscompeteforwater,nutrients,andlight andextendthetimerequiredtoproduceamarketabletree. Successful weed control helps the grower produce high.Finally, reductionofweedsreducesinterferencewithlaborandequip- mentmovementandimprovestheplantation'sappearance forconsumers. Methods of Weed Control Site

  19. 36 CFR 222.8 - Cooperation in control of estray or unbranded livestock, animal diseases, noxious farm weeds, and...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...livestock, animal diseases, noxious farm weeds, and use of pesticides. 222.8 Section...livestock, animal diseases, noxious farm weeds, and use of pesticides. (a) Insofar...diseases, sanitation and noxious farm weeds. (2) The Animal and Plant...

  20. 36 CFR 222.8 - Cooperation in control of estray or unbranded livestock, animal diseases, noxious farm weeds, and...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...livestock, animal diseases, noxious farm weeds, and use of pesticides. 222.8 Section...livestock, animal diseases, noxious farm weeds, and use of pesticides. (a) Insofar...diseases, sanitation and noxious farm weeds. (2) The Animal and Plant...

  1. Published by: Virginia Cooperative Extension Content Coordinators: Chuan Hong, Department of Plant Pathology, Physiology and Weed Science

    E-print Network

    Liskiewicz, Maciej

    Pathology, Physiology and Weed Science Peter B. Schultz, Depatment of Entomology Produced by: Communications ................................................................ 2-25 Weeds........................................................................ 2-27 3 Grapes Diseases and Insects in Vineyards .............................. 3-1 Weed control in Vineyards

  2. 36 CFR 222.8 - Cooperation in control of estray or unbranded livestock, animal diseases, noxious farm weeds, and...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...livestock, animal diseases, noxious farm weeds, and use of pesticides. 222.8 Section...livestock, animal diseases, noxious farm weeds, and use of pesticides. (a) Insofar...diseases, sanitation and noxious farm weeds. (2) The Animal and Plant...

  3. 36 CFR 222.8 - Cooperation in control of estray or unbranded livestock, animal diseases, noxious farm weeds, and...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...livestock, animal diseases, noxious farm weeds, and use of pesticides. 222.8 Section...livestock, animal diseases, noxious farm weeds, and use of pesticides. (a) Insofar...diseases, sanitation and noxious farm weeds. (2) The Animal and Plant...

  4. Classification of a broadleaf weed, a grassy weed, and corn using image processing techniques

    NASA Astrophysics Data System (ADS)

    Dickson, Monte A.; Bausch, Walter C.; Howarth, M. Scott

    1995-01-01

    Development of a machine vision device to automatically identify different weed species within a field is needed to design a successful spatially variable herbicide applicator. This study was conducted to develop a computer vision algorithm that can successfully identify a broadleaf weed (velvetleaf, Abutilon theophrasti), a grassy weed (wild proso millet, Panicum miliacem), and corn (Zea mays, L.). Digital images were collected in laboratory and field conditions for all three plant species. Image analysis techniques were used to analyze the possibility of using a combination of size and shape features to produce a classification scheme. Two separate approaches were used to classify the velvetleaf from the wild proso millet and corn, and the wild proso millet from the corn. The first and second invariant central moment of inertia measurements along with plant perimeter were used to separate the velvetleaf from the monocot species. Due to the similar shapes of wild proso millet and corn, we were unable to classify the two species by only using size and shape features. Consequently, a two step approach was utilized. This involved using projected perimeter to determine the age (number of days after emergence) of the plant. By knowing the possible age of the plant, the wild proso millet and corn were classified using a combination of length and circularity. Future research will involve the evaluation of several other image features to determine the best classification scheme. Further data will also be collected from a library of laboratory and field images in order to increase the confidence interval of the classification scheme.

  5. Tillage and residue burning affects weed populations and seed banks.

    PubMed

    Narwal, S; Sindel, B M; Jessop, R S

    2006-01-01

    An integrated weed management approach requires alternative management practices to herbicide use such as tillage, crop rotations and cultural controls to reduce soil weed seed banks. The objective of this study was to examine the value of different tillage practices and stubble burning to exhaust the seed bank of common weeds from the northern grain region of Australia. Five tillage and burning treatments were incorporated in a field experiment, at Armidale (30 degrees 30'S, 151 degrees 40'E), New South Wales, Australia in July 2004 in a randomized block design replicated four times. The trial was continued and treatments repeated in July 2005 with all the mature plants from the first year being allowed to shed seed in their respective treatment plots. The treatments were (i) no tillage (NT), (ii) chisel ploughing (CP), (iii) mould board ploughing (MBP), (iv) wheat straw burning with no tillage (SBNT) and (v) wheat straw burning with chisel ploughing (SBC). Soil samples were collected before applying treatments and before the weeds flowered to establish the seed bank status of the various weeds in the soil. Wheat was sown after the tillage treatments. Burning treatments were only initiated in the second year, one month prior to tillage treatments. The major weeds present in the seed bank before initiating the trial were Polygonum aviculare, Sonchus oleraceus and Avena fatua. Tillage promoted the germination of other weeds like Hibiscus trionum, Medicago sativa, Vicia sp. and Phalaris paradoxa later in the season in 2004 and Convolvulus erubescens emerged as a new weed in 2005. The MBP treatment in 2004 reduced the weed biomass to a significantly lower level of 55 g/m2 than the other treatments of CP (118 g/m2) and NT plots (196 g/m2) (P < 0.05). However, in 2005 SBC and MBP treatments were similar in reducing the weed biomass. In 2004, the grain yield trend of wheat was significantly different between CP and NT, and MBP and NT (P < 0.05) with maximum yield of 5898 kg/ha in CP and 5731 kg/ha in MBP. Rainfall before the start of the second trial season promoted the germination of a large numbers of weeds. SBC and MBP treatments reduced the numbers of most of the individual weed species compared with CP, SBNT and NT. SBC was able to destroy a large proportion of seeds most likely through burning and burying some in the soil and was found to be the best treatment in exhausting the seed bank followed closely by MBP which probably buried large number of seeds deep in the soil and promoted others to germinate. CP might have buried some of the seeds in the top 5-10 cm but also promoted parts of the seed bank to germinate. SBNT and NT provided an ideal medium for weeds to germinate and resulted in heavy infestations of weeds. PMID:17390813

  6. Microfungal "weeds" in the leafcutter ant symbiosis.

    PubMed

    Rodrigues, A; Bacci, M; Mueller, U G; Ortiz, A; Pagnocca, F C

    2008-11-01

    Leafcutter ants (Formicidae: tribe Attini) are well-known insects that cultivate basidiomycete fungi (Agaricales: Lepiotaceae) as their principal food. Fungus gardens are monocultures of a single cultivar strain, but they also harbor a diverse assemblage of additional microbes with largely unknown roles in the symbiosis. Cultivar-attacking microfungi in the genus Escovopsis are specialized parasites found only in association with attine gardens. Evolutionary theory predicts that the low genetic diversity in monocultures should render ant gardens susceptible to a wide range of diseases, and additional parasites with roles similar to that of Escovopsis are expected to exist. We profiled the diversity of cultivable microfungi found in 37 nests from ten Acromyrmex species from Southern Brazil and compared this diversity to published surveys. Our study revealed a total of 85 microfungal strains. Fusarium oxysporum and Escovopsis were the predominant species in the surveyed gardens, infecting 40.5% and 27% of the nests, respectively. No specific relationship existed regarding microfungal species and ant-host species, ant substrate preference (dicot versus grass) or nesting habit. Molecular data indicated high genetic diversity among Escovopsis isolates. In contrast to the garden parasite, F. oxysporum strains are not specific parasites of the cultivated fungus because strains isolated from attine gardens have similar counterparts found in the environment. Overall, the survey indicates that saprophytic microfungi are prevalent in South American leafcutter ants. We discuss the antagonistic potential of these microorganisms as "weeds" in the ant-fungus symbiosis. PMID:18369523

  7. Plant-Soil Interactions, Weed Control, and Rice Tolerance as Affected by Saflufenacil 

    E-print Network

    Camargo, Edinalvo

    2012-10-19

    Saflufenacil is a new herbicide for broadleaf weed control. Limited information is available for crop tolerance, weed control and herbicide behavior in the rice environment. Studies were designed to 1 and 2) evaluate rice ...

  8. 75 FR 23151 - Noxious Weeds; Old World Climbing Fern and Maidenhair Creeper

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-05-03

    ...APHIS-2008-0097] Noxious Weeds; Old World Climbing Fern and Maidenhair Creeper AGENCY...noxious weed regulations by adding Old World climbing fern (Lygodium microphyllum...we amended the regulations by adding Old World climbing fern (Lygodium...

  9. Noxious Weed Monitoring at the US Air Force Academy-Year 2 Results

    E-print Network

    Noxious Weed Monitoring at the US Air Force Academy- Year 2 Results June 26, 2007 Prepared For: U....................................................................................................................... 11 TABLE OF TABLES Table 1. Noxious weed management objectives for species targeted in this study

  10. EFFECTS OF ORGANIC AND CONVENTIONAL PRACTICES ON WEED CONTROL IN A PERENNIAL CROPPING SYSTEM

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Vineyard weed communities were examined under the influence of an organic weed control practice, soil cultivation with a Clemens cultivator, and applications of the herbicide, glyphosate. Experimental treatments (winter-spring glyphosate, spring cultivation, fall-spring cultivation, fall cultivatio...

  11. Tolerance and weed management systems in imidazolinone tolerant corn (Zea mays L.)

    E-print Network

    Thompson, Ann Marie

    1999-01-01

    annuus L. ), This thesis follows the style and format of Weed Technology. broadleaf signalgrass [Brachiaria plaryphylla (Griseb. ) Nash], and yellow nutsedge (Cyperus esculenms L. ) (Dowler 1997). Traditionally, weed management in field corn has...

  12. Classification of Maize and Weeds by Bayesian Networks

    NASA Astrophysics Data System (ADS)

    Chapron, Michel; Oprea, Alina; Sultana, Bogdan; Assemat, Louis

    2007-11-01

    Precision Agriculture is concerned with all sorts of within-field variability, spatially and temporally, that reduces the efficacy of agronomic practices applied in a uniform way all over the field. Because of these sources of heterogeneity, uniform management actions strongly reduce the efficiency of the resource input to the crop (i.e. fertilization, water) or for the agrochemicals use for pest control (i.e. herbicide). Moreover, this low efficacy means high environmental cost (pollution) and reduced economic return for the farmer. Weed plants are one of these sources of variability for the crop, as they occur in patches in the field. Detecting the location, size and internal density of these patches, along with identification of main weed species involved, open the way to a site-specific weed control strategy, where only patches of weeds would receive the appropriate herbicide (type and dose). Herein, an automatic recognition method of vegetal species is described. First, the pixels of soil and vegetation are classified in two classes, then the vegetation part of the input image is segmented from the distance image by using the watershed method and finally the leaves of the vegetation are partitioned in two parts maize and weeds thanks to the two Bayesian networks.

  13. Engineering hypervirulence in a mycoherbicidal fungus for efficient weed control.

    PubMed

    Amsellem, Ziva; Cohen, Barry A; Gressel, Jonathan

    2002-10-01

    Agents proposed for biocontrol of major weeds in arable row-crop agriculture have not met expectations because an evolutionary balance has developed between microorganism and weed, even when the mycoherbicide is used inundatively at very high levels (>10(4)spores/cm<(2)). Sufficient virulence can be achieved by transferring genes to the microorganism, tipping the evolutionary balance. Virulence was increased ninefold and was more rapidly effected; furthermore, the requirement for a long duration at high humidity was decreased by introducing NEP1 encoding a phytotoxic protein, to an Abutilon theophrasti-specific, weakly mycoherbicidal strain of Colletotrichum coccodes. The parent strain was at best infective on juvenile cotyledons of this intransigent weed. The transgenic strain was lethal through the three-leaf stage, a sufficient time window to control this asynchronously germinating weed. Strategies of coupling virulence genes with fail-safe mechanisms to prevent spread (due to broadened host range) and to mitigate transgene introgression into crop pathogens could be very useful in the biocontrol of major weeds in row crops. PMID:12355116

  14. Competition Experiments on Alien Weeds with Crops: Lessons for Measuring Plant Invasion Impact?

    Microsoft Academic Search

    Montserrat Vilà; Mark Williamson; Mark Lonsdale

    2004-01-01

    Can we quantify the impact of invasive species? Here we use the per-plant competitiveness of alien weeds on crops as a model\\u000a of invasive species impact in general. We reviewed 97 weed–crop competition experiments in 32 papers that included 30 alien\\u000a weed and 14 crop species. The majority (68.92%) were randomised block designs where the alien weed had been either

  15. Weed Invasion Susceptibility Prediction (WISP) Model for Use with Geographic Information Systems

    Microsoft Academic Search

    J. H. Gillham; A. L. Hild; J. H. Johnson; E. R. Hunt; T. D. Whitson

    2004-01-01

    The Weed Invasion Susceptibility Prediction (WISP) model was developed as an extension of the ArcView Geographic Information System to predict potential risk of invasion by individual weed species in rangelands. Existence potential was determined by comparing growth requirements of each weed species with respect to nine site characteristics obtained from geographic data layers: distance from water and disturbance sources, elevation,

  16. Sweat, Brain-Power, Horsepower, and Time - The Keys to Controlling Weeds

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Weed control in organic crop production is difficult and costly. Early studies on organic weed control in conservation tillage systems were disappointing. Research shifted to organic weed control in conventional tillage systems. Intense cultivation with a tine weeder was the most consistent metho...

  17. Grass Carp: A Fish for Biological Management of Hydrilla and Other Aquatic Weeds in Florida1

    E-print Network

    Watson, Craig A.

    BUL867 Grass Carp: A Fish for Biological Management of Hydrilla and Other Aquatic Weeds in Florida1 visit the EDIS website at http://edis.ifas.ufl. edu. 2. David L. Sutton, professor (aquatic weeds), retired; Vernon V. Vandiver Jr., associate professor (aquatic weeds specialist), retired; and Jeffrey E

  18. Evolution of Weediness and Invasiveness: Charting the Course for Weed Genomics

    E-print Network

    Rieseberg, Loren

    Evolution of Weediness and Invasiveness: Charting the Course for Weed Genomics C. Neal Stewart, Jr and their evolution remain poorly understood, but genomic approaches offer tremendous promise for elucidating these important features of weed biology. However, the genomic tools and resources available for weed research

  19. WHY RAGWEED PARTHENIUM IS NOT A PERNICIOUS WEED IN THE CONTINENTAL USA?

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Ragweed parthenium has achieved major weed status in India and Australia within the past few decades. In the continental USA (48 contiguous states), ragweed parthenium is not a major weed despite close proximity to its native range. We provide rationale for why ragweed parthenium is not a major weed...

  20. STATUS OF BIOLOGICAL CONTROL OF WEEDS IN HAWAII AND IMPLICATIONS FOR MANAGING NATIVE ECOSYSTEMS

    Microsoft Academic Search

    George P. Markin; Po-Yung Lai; George Y. Funasaki

    Biological control of weeds in Hawaii dates back almost 90 years. Seventy-three species of insects and one disease organism have been introduced in an effort to control 21 species of weeds. Forty-three of these •introduced species of insects and one species of fungus have become established on 19 weeds. In 11 cases, populations of the phytophagous organisms have been sufficiently

  1. Integrating multiple tactics for managing weeds in high residue no-till soybean

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rolled cover crop mulches can suppress weeds in subsequent cash crops, reduce the need for herbicides and allow organic no-till cash crop establishment. This study investigated the weed suppressiveness of a cereal rye (Secale cereale L.) cover crop mulch across varying weed seedbank density. Cereal ...

  2. The effect of environmental conditions on the seasonal dormancy pattern and germination of weed seeds

    Microsoft Academic Search

    H. J. Bouwmeester

    1990-01-01

    Weeds cause considerable losses in horticultural and agricultural crops. Weeds are still predominantly controlled with herbicides. To reduce the use of chemicals, a better understanding of the biology of weeds is required. In this thesis the effect of environmental conditions on dormancy and germination of Chenopodium album L., Polygonum persicaria L., P. lapathifolium L. subsp. lapathifolium, Sisymbrium officinale (L.) Scop.

  3. Weed populations and crop rotations : Exploring dynamics of a structured periodic system

    Microsoft Academic Search

    Shana K. Mertens; Frank van den Bosch

    2002-01-01

    The periodic growing of a certain set of crops in a prescribed order, called a crop rotation, is considered to be an important tool for managing weed populations. Nevertheless, the effects of crop rotations on weed population dynamics are not well understood. Explanations for rotation effects on weed populations usually invoke the diversity of environments caused by different crops that

  4. Development of the Alaska agricultural weed flora 1981-2004: a case for prevention

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Agricultural fields in Alaska were surveyed in 2004, 23 years after a similar 1981 study, to determine if new weed species had been introduced and whether different environmental and management variables were correlated field weed species composition. Percent cover of each weed species was determine...

  5. ECOLOGICAL ASPECTS OF WEED F'LORAINAN IRRIGATED RICE FIEW) ECOSYSTEM AT BATHALAGODA IN SRI LANRA

    Microsoft Academic Search

    C. N. B. BAMBARADENIYA; C. V. S. GUNATILLEKE

    2002-01-01

    This study was carried out to document some ecological aspects of weeds in an irrigated rice field ecosystem in Bathalagoda, Sri Lanka. The study was conducted from November 1995 to August 1997 in two rice fields which differed in weed management practices. A total of 89 vascular plant species of rice-weeds belonging to 21 families, 31 genera of algae and

  6. Decomposition dynamics of invasive alligator weed compared with native sedges in a Northland lake

    Microsoft Academic Search

    Imogen E. Bassett; Jacqueline R. Beggs; Quentin Paynter

    2010-01-01

    Invasive weeds have been shown to alter ecosystem processes such as decomposition and nutrient cycling. However, little is known about the effects of introduced biocontrol agents on these processes. This study examined the effects of alligator weed (Alternanthera philoxeroides) and its biocontrol agent, the alligator weed flea beetle (Agasicles hygrophila), on nutrient cycling in a northern New Zealand lake. Alligator

  7. Residual Weeds of Processing Sweet Corn in the North Central Region

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Knowledge of weed community structure in vegetable crops of the North Central Region (NCR) is poor. To characterize weed composition of species persisting in sweet corn to harvest, hereafter called residual weeds, 175 sweet corn fields were surveyed in Illinois, Minnesota, and Wisconsin from 2005 to...

  8. Genomics of compositae weeds: EST libraries, microarrays, and evidence of introgression

    Technology Transfer Automated Retrieval System (TEKTRAN)

    • Premise of Study: Weeds cause considerable environmental and economic damage. However, genomic characterization of weeds has lagged behind that of model plants and crop species. Here we report on the development of genomic tools and resources for 11 weeds from the Compositae family that can serve ...

  9. Wavelet transform to discriminate between crop and weed in agronomic images

    Microsoft Academic Search

    Jérémie Bossu; Christelle Gée; Frédéric Truchetet

    2007-01-01

    In precision agriculture, the reduction of herbicide applications requires an accurate detection of weed patches. From image detection, to quantify weed infestations, it would be necessary to identify crop rows from line detection algorithm and to discriminate weed from crop. Our laboratory developed several methods for line detection based on Hough Transform, double Hough Transform or Gabor filtering. The Hough

  10. Assessment of current weed control methods relevant to the management of the biodiversity of Australian rangelands

    Microsoft Academic Search

    J. S. Vitelli; J. L. Pitt

    2006-01-01

    The Australian rangelands contain extensive and often dense populations of a wide variety of weed species. An array of techniques is available for effectively controlling many of these. To achieve long-term weed control, weeds should be targeted objectively and the dependence on the use of single treatments such as herbicides and machinery reduced, with greater adoption of integrated methods. The

  11. RESEARCH ARTICLE Remarkable changes of weed species in Spanish cereal fields

    E-print Network

    Paris-Sud XI, Université de

    RESEARCH ARTICLE Remarkable changes of weed species in Spanish cereal fields from 1976 to 2007 gradients and climatic factors are factors explaining weed species composition and richness in cereal fields from Northern and Central Europe. In the Mediterranean area, the precise factors responsible for weed

  12. Influence of Planting Date and Weed Interference on Sweet Corn Growth and Development

    E-print Network

    Sims, Gerald K.

    Influence of Planting Date and Weed Interference on Sweet Corn Growth and Development Martin M- tween weeds and sweet corn (Zea mays L.); however, little is known about sweet corn growth response to weed interference. Field studies were conducted in 2004 and 2005 near Urbana, IL, to quantify

  13. Volunteer Potato Density Influences Critical Time of Weed Removal in Bulb Onion

    E-print Network

    Sims, Gerald K.

    Volunteer Potato Density Influences Critical Time of Weed Removal in Bulb Onion Martin M. Williams control tactics are effective for removing this weed from an onion crop. Both volunteer potato density density on the critical time of weed removal (CTWR) in onion. Yield losses of 2.5, 5.0, and 10% were

  14. Characteristics of Herbicides and Weed Management Programs Most Important to Corn, Cotton, and Soybean Growers

    E-print Network

    Mitchell, Paul D.

    Characteristics of Herbicides and Weed Management Programs Most Important to Corn, Cotton of Herbicides and Weed Management Programs Most Important to Corn, Cotton, and Soybean Growers T.M. Hurley in better understanding the characteristics of herbicides and weed management programs that are important

  15. South Carolina Pest Management Handbook for Field Crops -2014 AQUATIC WEED CONTROL

    E-print Network

    Duchowski, Andrew T.

    South Carolina Pest Management Handbook for Field Crops - 2014 297 AQUATIC WEED CONTROL Jack M. Whetstone, Extension Aquatic Specialist W. Cory Heaton, County Agent Aquatic weeds in ponds or lakes can will depend on factors such as target weeds, non-target plants, and what the water is used for. Physical

  16. South Carolina Pest Management Handbook for Field Crops -2013 AQUATIC WEED CONTROL

    E-print Network

    Stuart, Steven J.

    South Carolina Pest Management Handbook for Field Crops - 2013 284 AQUATIC WEED CONTROL Jack M. Whetstone, Extension Aquatic Specialist W. Cory Heaton, County Agent Aquatic weeds in ponds or lakes can will depend on factors such as target weeds, non-target plants, and what the water is used for. Physical

  17. Population-based threshold models describe weed germination and emergence patterns across varying

    E-print Network

    Bradford, Kent

    Population-based threshold models describe weed germination and emergence patterns across varying and success of control measures often hinges on the timing of weed emergence. We used population of herbicide-resistant and -susceptible Echinochloa phyllopogon, a weed of temperate paddy rice, and applied

  18. Data Weeding Techniques Applied to Roget's Thesaurus Uta Priss, L. John Old

    E-print Network

    Old, L. John

    Data Weeding Techniques Applied to Roget's Thesaurus Uta Priss, L. John Old Napier University- riety of "data weeding" techniques that can be applied in order to reduce the size of a concept lattice about which data to select resemble a form of "weeding" in a garden because whether a plant

  19. WEED CONTROL IN FLUE-CURED TOBACCO Charles S. Johnson, Extension Plant Pathologist, Tobacco

    E-print Network

    Buehrer, R. Michael

    WEED CONTROL IN FLUE-CURED TOBACCO Charles S. Johnson, Extension Plant Pathologist, Tobacco Good weed control uses crop rotation, early root and stalk destruction, cultivation, and appropriate use) will reduce reliance on tillage and cultivation for early season weed control. Some herbicides may also

  20. 7 CFR 201.65 - Noxious weed seeds in interstate commerce.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ...2010-01-01 2010-01-01 false Noxious weed seeds in interstate commerce. 201...REGULATIONS Tolerances § 201.65 Noxious weed seeds in interstate commerce. Tolerances for rates of occurrence of noxious-weed seeds shall be recognized and shall...

  1. 7 CFR 201.65 - Noxious-weed seeds in interstate commerce.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ...2013-01-01 2013-01-01 false Noxious-weed seeds in interstate commerce. 201...REGULATIONS Tolerances § 201.65 Noxious-weed seeds in interstate commerce. Tolerances for rates of occurrence of noxious-weed seeds shall be recognized and shall...

  2. Email not displaying correctly? View it in your browser. Mobile Weed Manual is Here!

    E-print Network

    Tennessee, University of

    Email not displaying correctly? View it in your browser. Mobile Weed Manual is Here! The University of Tennessee Turf & Ornamental Weed Science Team has put together a new website and free mobile app called "Mobile Weed Manual," #12;located at www.mobileweedmanual.com. It just went online this week

  3. Integration of soil, crop and weed management in low-external-input farming systems

    E-print Network

    Sims, Gerald K.

    Integration of soil, crop and weed management in low-external-input farming systems M LIEBMAN diversi®cation are basic components of LEI systems. Weed scientists can improve the use of these practices for weed management by improving knowledge of four relevant ecological mechanisms. First, multispecies crop

  4. 7 CFR 360.301 - Information required for applications for permits to move noxious weeds.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ...applications for permits to move noxious weeds. 360.301 Section 360.301 Agriculture...SERVICE, DEPARTMENT OF AGRICULTURE NOXIOUS WEED REGULATIONS § 360.301 Information...applications for permits to move noxious weeds. (a) Permit to import a noxious...

  5. Cooperative Coevolutionary Invasive Weed Optimization and its Application to Nash Equilibrium Search in Electricity Markets

    E-print Network

    Zhang, Richard "Hao"

    Cooperative Coevolutionary Invasive Weed Optimization and its Application to Nash Equilibrium and Intelligent Processing Center of Excellence University of Tehran, Iran Philosophy · Why Weeds? ·The most robust and troublous plant in agriculture. ·After thousands of tillage and hand-weeding we still have

  6. On the adequacy of GIS-generated weed maps for Precision Farming

    E-print Network

    Behnke, Sven

    On the adequacy of GIS-generated weed maps for Precision Farming Matthias Backes1 , Lutz Plümer1 1 an increasing importance in modern Precision Farming. For the application of herbicides in a field, maps of weed reason why farmers tend to be hesitant in applying the GIS-generated weed maps. In this paper, the lack

  7. 7 CFR 201.17 - Noxious-weed seeds in the District of Columbia.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ...2012-01-01 2012-01-01 false Noxious-weed seeds in the District of Columbia. 201...Agricultural Seeds § 201.17 Noxious-weed seeds in the District of Columbia. (a) Noxious-weed seeds in the District of Columbia are:...

  8. Linkages among agronomic, environmental and weed management characteristics in North American sweet corn

    E-print Network

    Sims, Gerald K.

    Linkages among agronomic, environmental and weed management characteristics in North American sweet-Agricultural Research Service, Invasive Weed Management Unit, 1102 S. Goodwin Ave., Urbana, IL 61801, USA b General practices and species interactions (Harper, 1977). In agroecosystems, knowledge of weed community structure

  9. Airborne hyperspectral and LiDAR data integration for weed detection

    NASA Astrophysics Data System (ADS)

    Tamás, János; Lehoczky, Éva; Fehér, János; Fórián, Tünde; Nagy, Attila; Bozsik, Éva; Gálya, Bernadett; Riczu, Péter

    2014-05-01

    Agriculture uses 70% of global available fresh water. However, ca. 50-70% of water used by cultivated plants, the rest of water transpirated by the weeds. Thus, to define the distribution of weeds is very important in precision agriculture and horticulture as well. To survey weeds on larger fields by traditional methods is often time consuming. Remote sensing instruments are useful to detect weeds in larger area. In our investigation a 3D airborne laser scanner (RIEGL LMS-Q680i) was used in agricultural field near Sopron to scouting weeds. Beside the airborne LiDAR, hyperspectral imaging system (AISA DUAL) and air photos helped to investigate weed coverage. The LiDAR survey was carried out at early April, 2012, before sprouting of cultivated plants. Thus, there could be detected emerging of weeds and direction of cultivation. However airborne LiDAR system was ideal to detect weeds, identification of weeds at species level was infeasible. Higher point density LiDAR - Terrestrial laser scanning - systems are appropriate to distinguish weed species. Based on the results, laser scanner is an effective tool to scouting of weeds. Appropriate weed detection and mapping systems could contribute to elaborate water and herbicide saving management technique. This publication was supported by the OTKA project K 105789.

  10. Direct and Indirect Impacts of Weed Management Practices on Soil Quality

    E-print Network

    Maxwell, Bruce D.

    275 18 Direct and Indirect Impacts of Weed Management Practices on Soil Quality Richard G. Smith, Matthew R. Ryan, and Fabian D. Menalled Weed management is an ever-present challenge to crop production. Weeds have the poten- tial to usurp resources that would otherwise provide nourishment to growing crops

  11. Weed Seed Survival in Livestock Systems Jeanie Katovich and Roger Becker

    E-print Network

    Minnesota, University of

    Weed Seed Survival in Livestock Systems Jeanie Katovich and Roger Becker Department of Agronomy to the soil. However, many assume manure is always rich in weed seeds. The opposite is probably the case as most of our harvested forage is relatively free of weed seeds. Exceptions obviously exist

  12. 7 CFR 201.65 - Noxious weed seeds in interstate commerce.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ...2011-01-01 2011-01-01 false Noxious weed seeds in interstate commerce. 201...REGULATIONS Tolerances § 201.65 Noxious weed seeds in interstate commerce. Tolerances for rates of occurrence of noxious-weed seeds shall be recognized and shall...

  13. Abstract--This paper presents a novel discrete population based stochastic optimization algorithm inspired from weed

    E-print Network

    Zhang, Richard "Hao"

    inspired from weed colonization. Its performance in a discrete benchmark, time- cost trade-off (TCT discrete invasive weed optimization (DIWO) algorithm for cooperative multiple task assignment of unmanned of the solutions and computational time. I. INTRODUCTION NVASIVE weed optimization (IWO) is a continuous

  14. Managing Weed Escapes in Roundup Ready Corn By Jeffrey L. Gunsolus

    E-print Network

    Minnesota, University of

    Managing Weed Escapes in Roundup Ready Corn By Jeffrey L. Gunsolus Professor and Extension Agronomist ­ Weed Science University of Minnesota Introduction Soybean producers have rapidly adopted as an easier method of conducting weed management. Currently, glyphosate and glufosinate are the key herbicide

  15. 7 CFR 360.301 - Information required for applications for permits to move noxious weeds.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ...applications for permits to move noxious weeds. 360.301 Section 360.301 Agriculture...SERVICE, DEPARTMENT OF AGRICULTURE NOXIOUS WEED REGULATIONS § 360.301 Information...applications for permits to move noxious weeds. (a) Permit to import a noxious...

  16. NEW YORK WEED SCIENCE FIELD DAY -2013 JULY 17 -WEDNESDAY H. C. THOMPSON RESEARCH FARM

    E-print Network

    Keinan, Alon

    NEW YORK WEED SCIENCE FIELD DAY - 2013 JULY 17 - WEDNESDAY ­ H. C. THOMPSON RESEARCH FARM Freeville a formal Weed Science Field Day at the H. C. Thompson Research Farm this year. If you want to see:30 p.m. Registration 1:30 - 4:30 p.m. Field Crop Weed Control (Russ Hahn) CCA and DEC Credits have been

  17. Data Weeding Techniques Applied to Roget's Thesaurus Uta Priss, L. John Old

    E-print Network

    Priss, Uta

    Data Weeding Techniques Applied to Roget's Thesaurus Uta Priss, L. John Old Edinburgh Napier- riety of "data weeding" techniques that can be applied in order to reduce the size of a concept lattice about which data to select resemble a form of filtering analogous to "weeding" in a garden, because

  18. WEED MANAGEMENT IN SHELTERBELTS IS important as unwanted plants can compete for moisture,

    E-print Network

    Maxwell, Bruce D.

    WEED MANAGEMENT IN SHELTERBELTS IS important as unwanted plants can compete for moisture, nutrients and light. Unmanaged shelterbelts can also serve as a source of weed propagules into surrounding habitats. If weeds are not properly managed they can reduce the growth and survival of desirable species in recently

  19. Effects of Weed Resistance Concerns and Resistance Management Practices on the Value of Roundup Ready Crops

    E-print Network

    Mitchell, Paul D.

    Effects of Weed Resistance Concerns and Resistance Management Practices on the Value of Roundup-commercial purposes by any means, provide that this copyright notice appears on all such copies. #12;1 Effects of Weed Tucson, AZ Abstract This study estimates grower benefits of Roundup-Ready® (RR) weed management programs

  20. Environmental Research 106 (2008) 203211 Associations between grass and weed pollen and emergency department

    E-print Network

    Long, Bernard

    2008-01-01

    Environmental Research 106 (2008) 203­211 Associations between grass and weed pollen and emergency the short-term effects of exposure to grass and weed pollen on emergency department visits and readmissions were found between weed pollen (including ragweed pollen) and emergency department visits 2 days after

  1. 7 CFR 201.17 - Noxious-weed seeds in the District of Columbia.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ...2013-01-01 2013-01-01 false Noxious-weed seeds in the District of Columbia. 201...Agricultural Seeds § 201.17 Noxious-weed seeds in the District of Columbia. (a) Noxious-weed seeds in the District of Columbia are:...

  2. 7 CFR 201.17 - Noxious-weed seeds in the District of Columbia.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ...2011-01-01 2011-01-01 false Noxious-weed seeds in the District of Columbia. 201...Agricultural Seeds § 201.17 Noxious-weed seeds in the District of Columbia. (a) Noxious-weed seeds in the District of Columbia are:...

  3. Effects of abiotic factors on species richness and cover in Central European weed communities

    E-print Network

    Kratochvíl, Lukas

    Effects of abiotic factors on species richness and cover in Central European weed communities Petr 2005; accepted 17 February 2005 Abstract Plant species richness and cover of 698 samples of weed flora variables on weed species number and cover, independent of covariance with other variables, were determined

  4. South Carolina Pest Management Handbook for Field Crops -2013 GRASS FORAGE WEED CONTROL

    E-print Network

    Stuart, Steven J.

    South Carolina Pest Management Handbook for Field Crops - 2013 116 GRASS FORAGE WEED CONTROL Mike Marshall, Extension Weed Specialist Newly Sprigged Bermudagrass Herbicide Rate/Acre Broadcast Mode: Apply OUTRIDER at 1.33 oz/A to control johnsongrass, yellow and purple nutsedge, and other weeds

  5. 7 CFR 201.65 - Noxious-weed seeds in interstate commerce.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ...2014-01-01 2014-01-01 false Noxious-weed seeds in interstate commerce. 201...REGULATIONS Tolerances § 201.65 Noxious-weed seeds in interstate commerce. Tolerances for rates of occurrence of noxious-weed seeds shall be recognized and shall...

  6. 7 CFR 201.17 - Noxious-weed seeds in the District of Columbia.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ...2014-01-01 2014-01-01 false Noxious-weed seeds in the District of Columbia. 201...Agricultural Seeds § 201.17 Noxious-weed seeds in the District of Columbia. (a) Noxious-weed seeds in the District of Columbia are:...

  7. Schnick et al.: Biocontrol of common dandelion 173 Weed Science, 50:173178. 2002

    E-print Network

    Boland, Greg J.

    Schnick et al.: Biocontrol of common dandelion · 173 Weed Science, 50:173­178. 2002 2,4-D@uoguelph.ca Integration of two or more methods in a weed control strategy may produce a positive interaction, possibly decreasing the cost or volume of use of herbicides in tradi- tional weed control strategies

  8. 7 CFR 360.301 - Information required for applications for permits to move noxious weeds.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ...applications for permits to move noxious weeds. 360.301 Section 360.301 Agriculture...SERVICE, DEPARTMENT OF AGRICULTURE NOXIOUS WEED REGULATIONS § 360.301 Information...applications for permits to move noxious weeds. (a) Permit to import a noxious...

  9. 7 CFR 360.301 - Information required for applications for permits to move noxious weeds.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ...applications for permits to move noxious weeds. 360.301 Section 360.301 Agriculture...SERVICE, DEPARTMENT OF AGRICULTURE NOXIOUS WEED REGULATIONS § 360.301 Information...applications for permits to move noxious weeds. (a) Permit to import a noxious...

  10. 7 CFR 201.65 - Noxious-weed seeds in interstate commerce.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ...2012-01-01 2012-01-01 false Noxious-weed seeds in interstate commerce. 201...REGULATIONS Tolerances § 201.65 Noxious-weed seeds in interstate commerce. Tolerances for rates of occurrence of noxious-weed seeds shall be recognized and shall...

  11. Implementation of Image Processing Technique in Real Time Vision System for Automatic Weeding Strategy

    Microsoft Academic Search

    M. M. Mustafa; A. Hussain; K. H. Ghazali; S. Riyadi

    2007-01-01

    A weed can be thought of as any plant growing in the wrong place at the wrong time and doing more harm than good. Weeds compete with the crop for water, light, nutrients and space, and therefore reduce crop yields and also affect the efficient use of machinery. The most widely used method for weed control is to use agricultural

  12. Machine Vision System for Automatic Weeding Strategy using Image Processing Technique

    Microsoft Academic Search

    Kamarul Hawari Ghazali; Aini Hussain

    2008-01-01

    The most widely used method for weed control is to use agricultural chemicals (herbicides products). This heavy reliance on chemicals raises many environmental and economic concerns, causing many plantation companies to seek alternatives for weed control in order to reduce chemical usage in their plantation. Since manual labor is costly and expensive, an automated weed control system may be economically

  13. Potential synergistic effects of cereal rye biomass and soybean planting density on weed suppression

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Increasing crop density is a cultural weed management practice that can complement the use of cover crops for weed suppression. In this research, we created a range of cover crop biomass and soybean densities in order to assess their weed suppressive ability alone and in combination. The experiment ...

  14. Weed management practices for organic production of trailing blackberry. I. Plant growth and early fruit production

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Weed management practices were evaluated in a new field of trailing blackberry established in western Oregon. The field was planted in May 2010 and certified organic in May 2012. Treatments included two cultivars, ‘Marion’ and ‘Black Diamond’, grown in 1) non-weeded plots, where weeds were cut to th...

  15. Poisonous weed species and their significance for cattle production in Serbia region

    Microsoft Academic Search

    Konstantinovic Branko; Meseldzija Maja

    Weed species that grow on agricultural land together with crop plants cause crop yield reduction and increased costs of agricultural production due to the cost of their control. Beside these direct damages, some weed species cause indirect damages by their adverse effects to human and domestic animals health. In our agroecological conditions the most problematic poisonous weed species are: Solanum

  16. TWIN-ROW SPACING DOES NOT AFFECT WEED FREE CRITICAL PERIOD IN CONSERVATION-TILLAGE CORN.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The critical period for weed control is the crop growth stage when weeds must be controlled to prevent cash crop yield losses. Field trials were conducted at the E.V. Smith Research and Extension Center near Shorter, AL, in 2004 and 2005 to compare the critical period for weed control in twin (19 c...

  17. The Effect of Farmyard Manure Anaerobic Treatment on Weed Seed Viability

    Microsoft Academic Search

    B. Šarapatka; M. Holub; M. Lhotská

    1993-01-01

    Weed encroachment is a serious problem of contemporary agriculture. Farmyard manure and other organic fertilizers can be major sources of weed seeds that get into the soil. One of the methods for eliminating weed seed germination is the technology of anaerobic treatment of the farmyard manure with a simultaneous production of biogas, the so called “Olomouc method”.Before anaerobic fermentation seeds

  18. 11:776:402 Weeds: Impact & Management in Urban Landscapes (WIMUL) (3 credits)

    E-print Network

    Chen, Kuang-Yu

    11:776:402 Weeds: Impact & Management in Urban Landscapes (WIMUL) (3 credits) Normally OfferedCompanion Description: This is a senior level course which, in three modules, examines the impact of weeds in urban.); industrial sites; rights of way (rails & roads); etc. Module 1 of WIMUL covers the basic principles of weed

  19. Managing Weeds in Dry Peas Agronomic and market considerations have sparked an

    E-print Network

    Maxwell, Bruce D.

    Managing Weeds in Dry Peas Agronomic and market considerations have sparked an increased interest in incorporating dry peas into their crop rotation should be aware of the associated weed management challenges to inadequate weed management. For example, a wild oat density of 4 plants/ft2 can lead to a 51 percent loss

  20. The practical reason of weeds in Indonesia: Peasant vs. state views of Imperata and Chromolaena

    Microsoft Academic Search

    Michael R. Dove

    1986-01-01

    Peasant and state perceptions of two common weeds, Imperata cylindricaand Chromolaena odorata,are compared in four case study areas in Indonesia. Peasant perceptions are found to vary according to the similarity between these weeds plants and the fallow period vegetation in any given system of cultivation. All peasants attribute the origins of these weeds to external political authorities. State perceptions of

  1. Allelopathic potential of an annual weed, Polypogon monspeliensis , in crops in India

    Microsoft Academic Search

    Inderjit; K. M. M. Dakshini

    1995-01-01

    The question of whether annual weeds are allelopathic under natural conditions still remains to be critically answered. Investigations were carried out to understand the involvement and mode of operation of allelopathy in an annual weed, Polypogon monspeliensis. Comparative studies of soils associated with and without the weed under field conditions revealed that there was no significant difference in toxicity of

  2. Broadcast application of Racer for broadleaf weed control in spring-transplanted onions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Controlling weeds can be a costly and time consuming process and uncontrolled weeds can reduce or eliminate crop yields and profits. In conventional agriculture, the use of herbicides provides a valuable tool within an integrated weed control system, but there are very few organically approved her...

  3. VINEYARD WEED SEEDBANK COMPOSITION RESPONDS TO GLYPHOSATE AND CULTIVATION AFTER THREE YEARS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Herbicide and tillage have been shown to influence weed seedbank composition in annual cropping systems, but little information is available for perennial cropping systems like vineyards, where weed control practices are comparatively less intensive. We hypothesized that vineyard weed seedbanks woul...

  4. Comparison of some winter lentil cultivars in weed–crop competition

    Microsoft Academic Search

    Isik Tepe; M. Erman; A. Yazlik; R. Levent; K. Ipek

    2005-01-01

    The differential competitive ability of six winter lentil (Lens culinaris Medik.) cultivars and the traits that may confer such attributes was investigated in the presence or absence of weeds in a naturally occurring weed flora during 1997–1999 in Van, Turkey. For this purpose, six different winter lentil cultivars were used. The differences among the cultivars were not significant for weed

  5. Establishing a weed prevention area, a step-by-step user's guide

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Traditionally, weed management activities are only initiated after a weed has become a major economic problem in an area. This guide provides a process for individuals interested in developing community based weed prevention areas (WPA) to take a proactive approach to invasive species management. ...

  6. Managing Weeds in Lentils In recent years there has been increased interest in

    E-print Network

    Maxwell, Bruce D.

    Managing Weeds in Lentils In recent years there has been increased interest in diversifying Montana's cropping systems through the inclusion of pulse crops such as peas, dry beans, chickpeas, and lentils and opportunities of managing weeds in these crops. Weed management in lentils is of particular importance

  7. Smoking the Other: marijuana and counterhegemony in Weeds.

    PubMed

    Lavoie, Dusty

    2011-01-01

    Subverting suburban modernity, the SHOWTIME television series Weeds invites its audiences to situate their opinions about marijuana amid spheres of bourgeois soccer-moms, class politics, turf wars, raw economics, violent milieux, and multiculti heterogeneity. I argue that Weeds encourages us to "smoke the Other"; that is, to hesitantly accept difference, in line with many drug circles' etiquette. The phrase "smoking the Other" is a critical alteration of bell hooks' (1992, Black looks: Race and representation. Boston: South End Press) conception of whites' ethnic "devouring" as "eating the Other," a rather rigid schematic itself problematized by Weeds' transgressive self-conscious playfulness with stereotyped ethnicities, loopy plotlines, and counterhegemonic dialogue. Cultural/political implications follow. PMID:21599507

  8. Phenological observations on shrubs to predict weed emergence in turf

    NASA Astrophysics Data System (ADS)

    Masin, Roberta; Zuin, Maria Clara; Zanin, Giuseppe

    2005-09-01

    Phenology is the study of periodic biological events. If we can find easily recognizable events in common plants that precede or coincide with weed emergences, these plants could be used as indicators. Weed seedlings are usually difficult to detect in turf, so the use of phenological indicators may provide an alternative approach to predict the time when a weed appears and consequently guide management decisions. A study was undertaken to determine whether the phenological phases of some plants could serve as reliable indicators of time of weed emergence in turf. The phenology of six shrubs (Crataegus monogyna Jacq., Forsythia viridissima Lindl., Sambucus nigra L., Syringa vulgaris L., Rosa multiflora Thunb., Ziziphus jujuba Miller) and a perennial herbaceous plant [Cynodon dactylon (L.) Pers.] was observed and the emergence dynamics of four annual weed species [Digitaria sanguinalis (L.) Scop., Eleusine indica (L.) Gaertner, Setaria glauca (L.) Beauv., Setaria viridis (L.) Beauv.] were studied from 1999 to 2004 in northern Italy. A correlation between certain events and weed emergence was verified. S. vulgaris and F. viridissima appear to be the best indicators: there is a quite close correspondence between the appearance of D. sanguinalis and lilac flowering and between the beginning of emergence of E. indica and the end of lilac flowering; emergences of S. glauca and S. viridis were predicted well in relation to the end of forsythia flowering. Base temperatures and starting dates required to calculate the heat unit sums to reach and complete the flowering phase of the indicators were calculated using two different methods and the resultant cumulative growing degree days were compared.

  9. DOI: 10.1111/j.1365-3180.2010.00790.x Weighing abiotic and biotic influences on weed seed

    E-print Network

    Sims, Gerald K.

    DOI: 10.1111/j.1365-3180.2010.00790.x Weighing abiotic and biotic influences on weed seed predation A S DAVIS* & S RAGHU à *Invasive Weed Management Unit, Agricultural Research Service, United States 12 April 2010 Summary Weed seed predation is an important ecosystem service supporting weed

  10. Using Bayesian networks with rule extraction to infer the risk of weed infestation in a corn-crop

    Microsoft Academic Search

    Gláucia M. Bressan; Vilma A. de Oliveira; Estevam R. Hruschka Jr.; Maria do Carmo Nicoletti

    2009-01-01

    This paper describes the modeling of a weed infestation risk inference system that implements a collaborative inference scheme based on rules extracted from two Bayesian network classifiers. The first Bayesian classifier infers a categorical variable value for the weed–crop competitiveness using as input categorical variables for the total density of weeds and corresponding proportions of narrow and broad-leaved weeds. The

  11. Herbicide-resistant crops: utilities and limitations for herbicide-resistant weed management.

    PubMed

    Green, Jerry M; Owen, Micheal D K

    2011-06-01

    Since 1996, genetically modified herbicide-resistant (HR) crops, particularly glyphosate-resistant (GR) crops, have transformed the tactics that corn, soybean, and cotton growers use to manage weeds. The use of GR crops continues to grow, but weeds are adapting to the common practice of using only glyphosate to control weeds. Growers using only a single mode of action to manage weeds need to change to a more diverse array of herbicidal, mechanical, and cultural practices to maintain the effectiveness of glyphosate. Unfortunately, the introduction of GR crops and the high initial efficacy of glyphosate often lead to a decline in the use of other herbicide options and less investment by industry to discover new herbicide active ingredients. With some exceptions, most growers can still manage their weed problems with currently available selective and HR crop-enabled herbicides. However, current crop management systems are in jeopardy given the pace at which weed populations are evolving glyphosate resistance. New HR crop technologies will expand the utility of currently available herbicides and enable new interim solutions for growers to manage HR weeds, but will not replace the long-term need to diversify weed management tactics and discover herbicides with new modes of action. This paper reviews the strengths and weaknesses of anticipated weed management options and the best management practices that growers need to implement in HR crops to maximize the long-term benefits of current technologies and reduce weed shifts to difficult-to-control and HR weeds. PMID:20586458

  12. Biology, ecology and management of the invasive parthenium weed (Parthenium hysterophorus L.).

    PubMed

    Adkins, Steve; Shabbir, Asad

    2014-07-01

    Parthenium weed (Parthenium hysterophorus L.) is one of the most aggressive invasive weeds, threatening natural ecosystems and agroecosystems in over 30 countries worldwide. Parthenium weed causes losses of crops and pastures, degrading the biodiversity of natural plant communities, causing human and animal health hazards and resulting in serious economic losses to people and their interests in many countries around the globe. Several of its biological and ecological attributes contribute towards its invasiveness. Various management approaches (namely cultural, mechanical, chemical and biological control) have been used to minimise losses caused by this weed, but most of these approaches are ineffective and uneconomical and/or have limitations. Although chemical control using herbicides and biological control utilising exotic insects and pathogens have been found to contribute to the management of the weed, the weed nevertheless remains a significant problem. An integrated management approach is proposed here for the effective management of parthenium weed on a sustainable basis. PMID:24430973

  13. Weed Killer Deforms Sex Organs in Frogs, Study Finds

    NSDL National Science Digital Library

    Associated Press.

    This Web site discusses current research findings surrounding the use of the weed killer, atrazine, and sex organ deformities in frogs exposed to it. The article from the New York Times summarizes the recent research report; free registration is required to view it. This site reports focus on the potential impact of atrazine on humans, but they do raise it as an important question.

  14. Biological control of weeds in the tropics and sustainability

    E-print Network

    Reddy, Gadi VP

    ., 2007) and for invasive weed species to be recognized as an international problem (Harris, 1979). Since- logical control of invasive species and to maintain sustainable programs in the future. Biological Control limited resources, have not adopted deliberate measures for biological control of invasive plants

  15. Potential of Air-Propelled Abrasives for Selective Weed Control

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Novel forms of selective weed control are needed by many types of growers, but especially organic growers who are restricted from using synthetic herbicides. Abrasive grit made from corn cobs was expelled from a sand blaster at 517 kPa pressure and aimed at seedlings of common lambsquarters and corn...

  16. Response of Two Sweet Potato Cultivars to Weed Interference

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Field experiments were conducted at Charleston, SC to assess the effect of different durations of weed interference on two sweetpotato cultivars with distinctly different shoot growth habits. The cultivars were Beauregard, which has a spreading growth habit, and Carolina Bunch, which has an erect g...

  17. Solanum viarum: Weed reservoir of plant viruses in Florida

    Microsoft Academic Search

    R. J. McGovern; J. E. Polston; J. J. Mullahey

    1994-01-01

    Solanum viarum Dunal (tropical soda apple), an introduced and rapidly spreading weed, currently infests over 60 000 ha in Florida. Approximately 220 plants were sampled in seven stands of S. viarum in south?west and west central Florida during 1992 and 1993 to determine the occurrence of nine viruses which can infect solanaceous crops. Virus detection utilized a double antibody sandwich?enzyme

  18. LIBERTY TOLERANT COTTON: WEED CONTROL AND CROP TOLERANCE Brent Burns

    E-print Network

    Mukhtar, Saqib

    LIBERTY TOLERANT COTTON: WEED CONTROL AND CROP TOLERANCE Brent Burns Texas Tech University Lubbock Acres planted with herbicide-tolerant cotton varieties have steadily increased since their introduction in 1995. Recently, the bar gene was introduced into Coker 312 cotton plants for tolerance to Liberty

  19. Effectiveness of Eriophyid Mites for Biological Control of Weeds

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Eriophyid mites are thought to have a high potential for use as classical biological control agents of weeds. However, in the past 20 years few species have been authorized for introduction, and few have significantly reduced the target plant's population. Natural enemies, resistant plant genotype...

  20. Onion and weed response to mustard (Sinapis alba) seed meal

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Onion and weed response to mustard seed meal (MSM) were tested in greenhouse and field trials in 2007-2009. MSM was applied to the soil surface at rates of 1.1, 2.2, and 4.4 MT/ha. In greenhouse trials, onions were severely injured and stands reduced with all rates of MSM applied prior to onion emer...

  1. Mustard Seed Meal suppresses Weeds in Potato and Peppermint

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Seed meal is a co-product remaining after pressing mustard seed to remove the oil. Seed meals containing high glucosinolates have been reported to have herbicidal activity. Weed suppression with seed meal of Sinapis alba, variety Ida Gold was evaluated in field trials on potatoes and peppermint in ...

  2. Weed Management in No-Till Zucchini Squash

    Microsoft Academic Search

    S. Alan Walters; Bryan G. Young

    2011-01-01

    Weed control in no-tillage (NT) zucchini squash (Cucurbita pepo L.) was determined for various preemergence (PRE) herbicide combinations in herbicide-killed ‘Wheeler’ winter rye (Secale cereale L.) or bare soil. Winter rye provided 65% and 75% control of redroot pigweed (Amaranthus retroflexus L.) and smooth crabgrass [Digitaria ischaemum (Schreb.) Schreb. ex Muhl.], respectively, in the absence of herbicides compared with no

  3. HYDRILLA, THE PERFECT AQUATIC WEED, BECOMES MORE NOXIOUS THAN EVER

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Hydrilla [Hydrilla verticillata (L.F.) Royale] was introduced in Florida lakes 50 years ago and is now one of the most serious aquatic weed problems in the United States. This plant possesses numerous mechanisms of vegetative reproduction that enables it to spread very rapidly. Management of this ...

  4. Management of winter weeds affects Frankliniella fusca (Thysanoptera: Thripidae) dispersal.

    PubMed

    Beaudoin, A L P; Kennedy, G G

    2012-04-01

    Frankliniella fusca (Hinds) naturally disperses from winter weeds to crops in spring, causing direct and indirect damage. Field preparation before planting includes use of herbicides or cultivation to kill unwanted vegetation, which adversely affects F. fusca host plants and potentially influences F. fusca dispersal. Common chickweed, Stellaria media (L.), infested with F. fusca, was used as a model to study effects of timing and type of vegetation management on adult dispersal. Infested weeds were caged and F. fusca weekly dispersal was monitored using sticky traps. Weed management treatments performed at an early (14 April-11 May) or late (2 wk after early treatment) date consisted of glyphosate, paraquat, disking, hoeing, or untreated control. Late glyphosate and hoeing treatments resulted in cumulative dispersal statistically similar to or greater than from control plots. Compared with the control, significantly more F. fusca dispersed from the glyphosate and hoeing plots during the 3 wk after treatment. More thrips dispersed from the late paraquat treatment 1 wk post-application than from the control. Dispersal from the disked treatment and early paraquat treatment was similar to that of the control 1- to 3-wk post-treatment. Early treatments resulted in significantly smaller cumulative dispersal than the control in all but one instance. Late disking and paraquat treatments resulted in cumulative F. fusca captures that were statistically similar or less than that in the control. Winter weed management type and timing affect F. fusca dispersal magnitude and duration. PMID:22507010

  5. A new approach to weed management, based on population dynamics

    Technology Transfer Automated Retrieval System (TEKTRAN)

    No-till cropping systems are improving precipitation-use-efficiency, increasing land productivity, and restoring soil health in semiarid regions of the world. However, weed resistance, rising costs, and concern about environmental impacts are stimulating questions about the extensive reliance on he...

  6. Effect of intermittent irrigation on rice productivity and weed suppression

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Certain indica rice lines from Asia have been shown to suppress barnyardgrass (Echinochloa crus-galli) effectively in conventional flood-irrigated (FLI) production systems, but their weed suppression potential in “intermittent flood-irrigated” (IFI) production systems is unknown. IFI systems (aka “...

  7. Corn gluten meal: Application options for a weed control alternative

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Weed control is a limiting factor in organic vegetable production. It has been reported that corn gluten meal (CGM) has preemergnce herbicide properties that may be useful in organic vegetable production. However, studies with CGM in vegetables are limited, in part due to the need for an effective m...

  8. Corn gluten meal for weed control in cowpea, Spring 2008

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Cowpea is a major vegetable crop within Oklahoma. It is utilized as both a processing crop by the canning industry and as a fresh market crop for farmer’s and roadside markets. Traditionally weed control in this crop is with preemergence and some postemergence herbicides, but recently fresh market...

  9. Weed control in lentil (Lens culinaris) in eastern Turkey

    Microsoft Academic Search

    Erdal Elkoca; Faik Kantar; Huseyin Zengin

    2005-01-01

    This study investigated the effect of 12 herbicide applications and hand weeding (once, twice, and repeated) in comparison with a weedy control on seed and total crop biomass yield of lentil (Lens culinaris) in 2000 and 2001 under the dry conditions of Erzurum (29°55'N and 41° 16'E at an altitude of 1850 m), Turkey. In both growing seasons, data were

  10. Response of `Alamo` switchgrass (Panicum virgatum) to weed management practices

    SciTech Connect

    Sledge, S.L.; Walker, R.H. [Auburn Univ., AL (United States)

    1995-11-01

    Field studies were conducted in 1992 and 1994 to evaluate herbicides that would provide weed control and biomass yield of `Alamo` switchgrass during the year of establishment. For grass weed control, bensulide was applied preplant incorporated (PPI) at 4.4 kg ai ha{sup -1}, while MSMA was applied postemergence over the top (POST) at 2.2 kg ai ha{sup -1} to switchgrass that had two to four leaves. Herbicides applied POST for control of broadleaf weed species included 2,4-D at 0.6 kg ai ha{sup -1} or metsulfuron at 0.02 kg ai ha{sup -1}. Herbicide treatments included bensulide and MSMA applied alone or in combination with s,3-D or metsulfuron. They were arranged in a randomized complete block design and replicated four times. Weed control, crop tolerance and yield data were taken over time. Bensulide or MSMA applied alone provided 80% or greater control of large crabgrass, broadleaf signalgrass and fall panicum for the two years. The addition of metsulfuron or 2,4-D provided acceptable control of smooth pigweed, prickly sida, pitted morningglory and sicklepod. MSMA treatments produced slight PANVI injury that ranged from 20 to 36%. Bensulide injury was mostly moderate ranging from 19 to 88%. Although less injury was recorded with MSMA treatments, bensulide treatments trended higher for establishment-year biomass production that averaged 5123 kg ha{sup -1} as compared to 4239 kg ha{sup -1} for MSMA treatments.

  11. ECOLOGICAL IMPACT OF INTEGRATED CHEMICAL AND BIOLOGICAL AQUATIC WEED CONTROL

    EPA Science Inventory

    This final report presents results of a four-year study of the ecological impacts of chemical, biological, and integrated methods of aquatic weed control. Biological and water quality changes occurred as abundance of macrophytic vegetation was altered by natural factors or manage...

  12. Organic weed control in certified organic watermelon production

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The increasing perception by consumers that organic food tastes better and is healthier continues to expand the demand for organically produced crops. Field research was conducted in southeast Oklahoma to determine the impact of organic production systems on weed control and watermelon (Citrullus l...

  13. Robust crop and weed segmentation under uncontrolled outdoor illumination

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A new machine vision for weed detection was developed from RGB color model images. Processes included in the algorithm for the detection were excessive green conversion, threshold value computation by statistical analysis, adaptive image segmentation by adjusting the threshold value, median filter, ...

  14. Selecting for Weed Resistance: Herbicide Rotation and Mixture

    Microsoft Academic Search

    Hugh J. Beckie; Xavier Reboud

    2009-01-01

    Herbicide rotations and mixtures are widely recommended to manage herbicide resistance. However, little research has quantified how these practices actually affect the selection of herbicide resistance in weeds. A 4-yr experiment was conducted in western Canada from 2004 to 2007 to examine the impact of herbicide rotation and mixture in selecting for acetolactate synthase (ALS) inhibitor resistance in the annual

  15. Weed Community and Glyphosate Management in Soybean Crops

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A concern to some conservationists is the loss of biodiversity of weedy plant species in the face of wide-spread adoption by farmers of transgenic crops that are resistant to broad-spectrum herbicides such as glyphosate. We studied weed biodiversity in both Argentina and the USA, the two countries w...

  16. COVER CROP SYSTEMS AFFECT WEED COMMUNITIES IN A CALIFORNIA VINEYARD

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Vineyard weed communities were examined under four dormant season cover crop systems representative of those used in the north-coastal grape-growing region of California: no-till annuals (rose clover, soft brome, zorro fescue; ANoT), no-till perennials (blue wildrye, California brome, meadow barley,...

  17. Corn gluten meal application equipment evaluations for organic weed control

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Corn gluten meal (CGM) produces an inhibitory effect and reduces root formation in several weed species. One limitation to further use of CGM in vegetable production is the difficulty in achieving a uniform application to the soil surface and detrimental impact of CGM on direct-seeded vegetables. ...

  18. NEW DEVELOPMENTS IN THE BIOLOGICAL CONTROL OF INVASIVE WEEDS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Six insects attacking yellow starthistle are widespread in California's central valley but have not substantially reduced weed populations. The accidentally introduced, false peacock fly is now widespread, but appears to pose no risk to native Cirsium thistles and negligible risk to safflower produ...

  19. Glufosinate treatment of weeds results in ammonia emission by plants

    Microsoft Academic Search

    Remy Manderscheid; Stefan Schaaf; Marie Mattsson; Jan K. Schjoerring

    2005-01-01

    The herbicide glufosinate, which is also called phosphinothricin (PPT), is known to inhibit glutamine synthetase and thus causes a blockage of ammonium (re)assimilation in plants. The objective of the present study was to test whether application of this herbicide results in an ammonia volatilization from the plants and to quantify nitrogen loss via ammonia emission. Four different weed species (Chenopodium

  20. Waterhyacinth: Florida's Worst Floating Weed1 Lyn A. Gettys2

    E-print Network

    Watson, Craig A.

    be spread in other ways. For example, small plants easily become caught in boat trailers or live wellsSS-AGR-380 Waterhyacinth: Florida's Worst Floating Weed1 Lyn A. Gettys2 1. This document is SS in Brazil and has invaded ecosystems throughout the world. The first documented broad introduction

  1. RISING CARBON DIOXIDE & IMPLICATIONS FOR WEED CROP MANAGEMENT

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The ongoing increase in atmospheric carbon dioxide (CO2), and associated changes in temperature and precipitation will almost certainly alter the growth, reproduction, and location of weedy species, with subsequent effects on weed/crop competition. In the review of data presented here, I examine th...

  2. Image Processing Performance Assessment Using Crop Weed Competition Models

    Microsoft Academic Search

    Christine Onyango; John Marchant; Andrea Grundy; Kath Phelps; Richard Reader

    2005-01-01

    Precision treatment of both crops and weeds requires the accurate identification of both types of plant. However both identification and treatment methods are subject to error and it is important to understand how misclassification errors affect crop yield. This paper describes the use of a conductance growth model to quantify the effect of misclassification errors caused by an image analysis

  3. Biomass Based Weed-Crop Competitiveness Classification Using Bayesian Networks

    Microsoft Academic Search

    Glaucia M. Bressan; Vilma A. Oliveira; Estevam R. Hruschka Jr; Maria C. Nicoletti

    2007-01-01

    This paper describes the modeling of a biomass based weed-crop competitiveness classification process, based on a Bayesian network classifier. The understandability of the model is improved by its automatic translation into a set of classification rules, which are easily understood by human beings. The Bayes approach is based on empirical data collected in a corn-crop and uses the concept of

  4. An application of soft sets in weed identification

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Soft set theory is originally proposed as a general mathematical tool for dealing with uncertainties present in most of our real life. This study applied soft sets to improve low accuracy of weed identification caused by similar features. Firstly, three types of plant leaf features including shape, ...

  5. Genetic diversity of alligator weed in China by RAPD analysis

    Microsoft Academic Search

    Cheng-Yuan Xu; Wen-Ju Zhang; Cui-Zhang Fu; Bao-Rong Lu

    2003-01-01

    Random amplified polymorphic DNA (RAPD) was applied to analyze geneticdiversity of an invasive weedy species, alligator weed (Alternantheraphiloxeroides (Martius) Grisebach), collected from eight differentsites in southern China. Amplified by 108 RAPD primers, 391 bands wereidentified from samples collected from three of the eight sites withconsiderably large spatial intervals, but no genetic variation was detectedamong the samples. A total number of

  6. 2009 Herbicide Recommendations for Specific Weed Problems In Forages

    E-print Network

    New Hampshire, University of

    temperature is expected to exceed 70o for three consecutive days Annual and perennial grass in emerged or established legume seeding POAST PLUS 1.5 pt. for annual grasses; 1.875 -2.25 pt. for perennial grasses POST Apply before weeds reach 8 inches in height. Control of perennial grasses is best accomplished

  7. Weed control and canopy light management in blackberries

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Weed control in blackberries (Rubus spp.) is a serious problem for organic producers and those who wish to reduce their reliance on herbicides. At the southern limits of blackberry production, late season yields are reduced because of high day-time temperatures generated by solar irradiation and ot...

  8. Confused about Fusion? Weed Your Science Collection with a Pro.

    ERIC Educational Resources Information Center

    O'Dell, Charli

    1998-01-01

    Provides guidelines on weeding science collections in junior high/high school libraries. Highlights include checking copyright dates, online sources, 13 science subject areas that deserve special consideration (plate tectonics, fission, fusion, radioactive dating, weather/climate, astronomy/space science, elements, integrated science,…

  9. Weed control in rice with metham-sodium.

    PubMed

    Sparacino, A C; Ferro, R; Riva, N; Ditto, D; Tano, F; Croce, G; Rabasse, J M

    2006-01-01

    Metam-sodium is a soil fumigant with herbicidal properties. A field experiment was conducted in 2000 at Copiano (Pavia, Italy) to determine the efficacy of three rates of metam-sodium (300, 450 and 600 l/ha) at three different planting times (5, 12 and 18 days after chemical treatments) for the control of weeds in rice cultivation. The study mainly focused on the control of red rice (Oryza sativa var. selvatica), a weed which is worldwide distributed in rice fields and difficult to eradicate Test design was a split-plot with four replications. The main plot size was 13, 5 by 15 m and the subplot size was 13, 5 by 5 m. The chemical treatments were carried out as pre-sowing. Two days after chemical treatments, all field plots were flooded with 10 cm of water as practiced locally. An early variety of rice (Loto) was sown at 150 kg/ha. Weed control was visually evaluated as a percentage of ground covering by all weeds and by each weed individually at three, four and five weeks after treatments. Observations were made also on rice selectivity, and rice grain yield was assessed at the end. Metam-sodium did not injure the rice plants. Metam-sodium at 450 l/ha controlled 100%, 97% and 92% of red rice at the first, second and third observations, respectively. Good results were also obtained with metam-sodium at 300 and 600 l/ha, which controlled 94 to 82% of red rice during the season. Echinochloa crus-galli was better controlled with the higher rates of metam-sodium, particularly in the early part of the season. Metam-sodium did not show enough efficacy in this study against Heteranthera reniformis, Bulboschoenus maritimus and Lindernia spp. The best rice grain yield was obtained with all rates of metam-sodium, when rice was sown 5 days after treatment. PMID:17390826

  10. Classical biological control of invasive teasels (Dipsacus spp.) and other weeds in areas of limited or restricted weed management

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Invasive teasels (Dipsacus spp.) are considered noxious in five states and listed as invasive in more than a dozen others, despite having little effect on agriculture. They are problematic in areas of limited weed management such as along highways and railroads and in ditches, wetlands and parks. A ...

  11. Allergens of weed pollen: an overview on recombinant and natural molecules.

    PubMed

    Gadermaier, Gabriele; Hauser, Michael; Ferreira, Fatima

    2014-03-01

    Weeds represent a botanically unrelated group of plants that usually lack commercial or aesthetical value. Pollen of allergenic weeds are able to trigger type I reactions in allergic patients and can be found in the plant families of Asteraceae, Amaranthaceae, Plantaginaceae, Urticaceae, and Euphorbiaceae. To date, 34 weed pollen allergens are listed in the IUIS allergen nomenclature database, which were physicochemically and immunologically characterized to varying degrees. Relevant allergens of weeds belong to the pectate lyase family, defensin-like family, Ole e 1-like family, non-specific lipid transfer protein 1 family and the pan-allergens profilin and polcalcins. This review provides an overview on weed pollen allergens primarily focusing on the molecular level. In particular, the characteristics and properties of purified recombinant allergens and hypoallergenic derivatives are described and their potential use in diagnosis and therapy of weed pollen allergy is discussed. PMID:23806644

  12. 7 CFR 360.303 - Approval of an application for a permit to move a noxious weed; conditions specified in permit.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ...application for a permit to move a noxious weed; conditions specified in permit. 360...SERVICE, DEPARTMENT OF AGRICULTURE NOXIOUS WEED REGULATIONS § 360.303 Approval of an application for a permit to move a noxious weed; conditions specified in permit....

  13. 7 CFR 360.303 - Approval of an application for a permit to move a noxious weed; conditions specified in permit.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ...application for a permit to move a noxious weed; conditions specified in permit. 360...SERVICE, DEPARTMENT OF AGRICULTURE NOXIOUS WEED REGULATIONS § 360.303 Approval of an application for a permit to move a noxious weed; conditions specified in permit....

  14. 7 CFR 360.303 - Approval of an application for a permit to move a noxious weed; conditions specified in permit.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ...application for a permit to move a noxious weed; conditions specified in permit. 360...SERVICE, DEPARTMENT OF AGRICULTURE NOXIOUS WEED REGULATIONS § 360.303 Approval of an application for a permit to move a noxious weed; conditions specified in permit....

  15. 7 CFR 360.303 - Approval of an application for a permit to move a noxious weed; conditions specified in permit.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ...application for a permit to move a noxious weed; conditions specified in permit. 360...SERVICE, DEPARTMENT OF AGRICULTURE NOXIOUS WEED REGULATIONS § 360.303 Approval of an application for a permit to move a noxious weed; conditions specified in permit....

  16. Weed hosts of Verticillium dahliae in crete: Susceptibility, symptomatology and significance

    Microsoft Academic Search

    E. K. Ligoxigakis; D. J. Vakalounakis; C. C. Thanassoulopoulos

    2002-01-01

    A survey of common and uncommon weed species usually showing Verticillium wilt symptoms was carried out during 1992–2000 in\\u000a Crete, Greece.Verticillium dahliae was isolated in 48 out of 182 sampled fields, in which several weed species were grown, from several locations in Oropedio,\\u000a Lasithi. Altogether, 124 isolates ofV. dahliae were recovered from the vascular stem-tissue of 19 weed species, belonging

  17. Weed Community Composition in Tree Fruit Nurseries Treated with Methyl Bromide and Alternative Fumigants

    Microsoft Academic Search

    Anil Shrestha; Greg T. Browne; Bruce D. Lampinen; Sally M. Schneider; Thomas J. Trout

    2009-01-01

    Many agricultural cropping systems have relied on methyl bromide (MeBr) for pest control, including weeds, for decades. Alternative fumigants are being sought worldwide because MeBr has been identified as an ozone-layer depleting substance. Weed communities respond dynamically to alterations in management systems. Thus, transition from MeBr to alternative fumigants may cause shifts in weed communities. This hypothesis was tested in

  18. Taxonomic and life history bias in herbicide resistant weeds: implications for deployment of resistant crops.

    PubMed

    Holt, Jodie S; Welles, Shana R; Silvera, Katia; Heap, Ian M; Heredia, Sylvia M; Martinez-Berdeja, Alejandra; Palenscar, Kai T; Sweet, Lynn C; Ellstrand, Norman C

    2013-01-01

    Evolved herbicide resistance (EHR) is an important agronomic problem and consequently a food security problem, as it jeopardizes herbicide effectiveness and increases the difficulty and cost of weed management. EHR in weeds was first reported in 1970 and the number of cases has accelerated dramatically over the last two decades. Despite 40 years of research on EHR, why some weeds evolve resistance and others do not is poorly understood. Here we ask whether weed species that have EHR are different from weeds in general. Comparing taxonomic and life history traits of weeds with EHR to a control group ("the world's worst weeds"), we found weeds with EHR significantly over-represented in certain plant families and having certain life history biases. In particular, resistance is overrepresented in Amaranthaceae, Brassicaceae and Poaceae relative to all weeds, and annuality is ca. 1.5 times as frequent in weeds with EHR as in the control group. Also, for perennial EHR weeds, vegetative reproduction is only 60% as frequent as in the control group. We found the same trends for subsets of weeds with EHR to acetolactate synthase (ALS), photosystem II (PSII), and 5-enolpyruvylshikimate-3-phosphate (EPSP) synthase-inhibitor herbicides and with multiple resistance. As herbicide resistant crops (transgenic or not) are increasingly deployed in developing countries, the problems of EHR could increase in those countries as it has in the USA if the selecting herbicides are heavily applied and appropriate management strategies are not employed. Given our analysis, we make some predictions about additional species that might evolve resistance. PMID:24039727

  19. Arbuscular mycorrhizal morphology in crops and associated weeds in tropical agro-ecosystems

    Microsoft Academic Search

    Thangavelu Muthukumar; Sampath Prakash

    2009-01-01

    Morphological types of arbuscular mycorrhizae (AM) in crops and associated weeds were examined in agro-ecosystems. In total,\\u000a 48 plant species (8 crops and 40 weeds) belonging to 43 genera in 18 families were examined. The number of plant species with\\u000a Arum-type AM was higher than those with Paris-type AM in the examined plants. AM association was absent in 6 weeds,

  20. An ecological approach to strengthen weed management in the semiarid great plains

    Microsoft Academic Search

    Randy Anderson

    2003-01-01

    Cropping systems in the semiarid Great Plains are rapidly changing. Previously, winter wheat–fallow was the prevalent system; now, because of no-till practices, producers are diversifying their rotations to include alternative crops. Yet, weed management is often ineffective because of herbicide-resistant weeds and low profit margins. A possible solution is ecologically based weed management, where cropping systems are designed to lower

  1. The weeds from the thatch roofs of medieval cottages from the south of England

    Microsoft Academic Search

    Dominique de Moulins

    2007-01-01

    Late medieval soot-coated thatch includes a number of very well preserved weeds as well as cereals or reeds. This paper investigates\\u000a the weeds from the thatch roofs of 13 cottages from the south of England. It describes the exceptional preservation of the\\u000a weeds which include plant parts rarely recorded in archaeological contexts and the information they can give about late

  2. A Tale of Two Depositories: Weeding Federal Depository Collections

    E-print Network

    Sare, Laura

    2009-01-01

    for depository libraries now that so many docu- ments are available online; often tangible copies in print or microfiche have been replaced by online revised editions. #31;e superseded copies need to be withdrawn so that the documents collection remains... the collection for the most part had never been weeded, many revised editions had never been withdrawn. Most of them were annual informational pamphlets sent out by agencies to describe their services to the public. In most cases, only the most recent...

  3. Preliminary screening of some Egyptian weeds for antimicrobial activity.

    PubMed

    El-Abyad, M S; Morsi, N M; Zaki, D A; Shaaban, M T

    1990-01-01

    Eleven Egyptian weeds collected from the Menoufeya district were screened for phytochemical compounds effective against several representatives of bacteria and yeasts. It was found that Soxhlet benzene extracts, especially those of Capsella bursa-pastoris (L.) Medik., were the most effective. Alkaloids and flavonoids of Capsella gave the highest antibiotic potencies and had the broadest antimicrobial spectra. It is suggested that these alkaloids might consist of yohimbine and ergocristine and the flavonoids included the flavone diosmin. PMID:2336037

  4. Weed flora of cereal crops in Canterbury, New Zealand

    Microsoft Academic Search

    G. W. Bourdöt; G. A. Hurrell; D. J. Saville

    1998-01-01

    Weed communities in Canterbury, New Zealand, cereal crops were characterised in the 1990–91, 1991–92, and 1992–93 growing seasons by measuring species population densities and harvest?time biomass in 39 and 45 fields respectively of wheat (Triticum aestivum) and barley (Hordeum vulgare) in the absence of herbicide treatments. A total of >57 species in >49 genera were recorded representing a total of

  5. Water Hyacinths and Alligator Weeds for Final Filtration of Sewage

    NASA Technical Reports Server (NTRS)

    Wolverton, B. C.; Mcdonald, R. C.; Gordon, J.

    1976-01-01

    The potential of water hyacinths (Eichhornia crassipes) (Mart.) Solms and alligator weeds (Alternanthera philoxerides) (Mart.) Griesb. as secondary and tertiary filtration systems for domestic sewage was demonstrated. These two vascular aquatic plants reduced the suspended solids, total Kjeldahl nitrogen, total phosphorus, BOD sub 5, and total organic carbon levels in domestic sewage from 60 percent to 98 percent within a two week period. These plants grown in domestic sewage were also free of toxic levels of trace heavy metals.

  6. Growth of a floating aquatic weed, Salvinia under standard conditions

    Microsoft Academic Search

    John J. Gaudet

    1973-01-01

    1.Growth of the floating aquatic weed, Salvinia, in sterile culture was exponential for at least 2 weeks under standardized conditions.2.Increase in light intensity or in CO2 resulted in increases in growth rate, but did not extend the exponential period of growth.3.This aquatic plant, like many others, discriminates against calcium relative to strontium.4.In culture Salvinia exhibited luxury consumption of N and

  7. The viscous mucilage from the weed Portulaca oleracea, L

    Microsoft Academic Search

    Guido E. Wenzel; J. D. Fontana; Joao B. C. Correa

    1990-01-01

    A polysaccharide complex has been extracted from the invasive and widespread weedPortulaca oleracea (purslane) in yields of up to 25 g% (dry wt). The clear and viscous mucilage displays physicochemical properties appropriate\\u000a for industrial uses, such as food extenders and viscosifier. Toxic collateral effects can be precluded because of the already\\u000a known uses in home remedies and animal feed. Anion

  8. Stratification Requirements for Seed Dormancy Alleviation in a Wetland Weed

    PubMed Central

    Boddy, Louis G.; Bradford, Kent J.; Fischer, Albert J.

    2013-01-01

    Echinochloaoryzicola(syn.E. phyllopogon) is an exotic weed of California rice paddies that has evolved resistance to multiple herbicides. Elimination of seedlingsthroughcertain weed control methods can limit the spread of this weed, but is contingent on accurate predictions of germination and emergence timing, which are influenced by seed dormancy levels.In summer annuals, dormancy can often be relieved through stratification, a period of prolonged exposure to cold and moist conditions.We used population-based threshold models to quantify the effects of stratification on seed germination of four E. Oryzicola populations at a range of water potential (?) and oxygen levels. We also determined how stratification temperatures, moisture levels and durations contributed to dormancy release. Stratification released dormancy by decreasing base ? and hydrotimerequired for germination and by eliminating any germination sensitivity to oxygen. Stratification also increased average germination rates (GR), which were used as a proxy for relative dormancy levels. Alternating temperatures nearly doubled GR in all populations, indicating that seeds could be partially dormant despite achieving high final germination percentages. Stratification at ??=?0 MPa increased GR compared to stratification at lower water potentials, demonstrating that ? contributed to regulating dormancy release. Maximum GR occurred after 2-4 weeks of stratification at 0 MPa; GR were often more rapid for herbicide-resistant than for herbicide-susceptible seeds, implying greater dormancy in the latter. Manipulation of field conditions to promote dormancy alleviation of E. oryzicola seeds might improve the rate and uniformity of germination for seed bank depletion through seedling weed control. Our results suggest field soil saturation in winter would contribute towards E. oryzicola dormancy release and decrease the time to seedling emergence. PMID:24039714

  9. Optimising diquat use for submerged aquatic weed management

    Microsoft Academic Search

    John Clayton; Fleur Matheson

    2010-01-01

    An experimentally derived prediction tool is under development which aims to assess potential deactivation of diquat caused\\u000a by water and deposits on plant leaf surfaces in New Zealand water bodies, where aquatic weeds are targeted for diquat treatment.\\u000a Optimising the use and success of diquat is important not only in managing public confidence in the use of aquatic herbicides,\\u000a but

  10. Herbicide-resistant weeds in Europe: the wider implications.

    PubMed

    Moss, S R

    2004-01-01

    Herbicide-resistance occurs in 55 weed species in 21 European countries. 91% of cases are associated with just four herbicide mode of action groups: ACCase and ALS inhibitors, and triazine and urea/amide photosynthetic inhibitors. There are also a few cases of resistance to bypiridiliums, dinitroanilnes and synthetic auxins. Resistance to ALS inhibitors tends to be less prevalent in Europe than elsewhere, but is likely to increase. A small scale survey showed that Alopecurus myosuroides is considered to be the most important herbicide-resistant weed in Europe at present. Lolium spp., and to a lesser extent Papaver rhoeas and Avena spp., were also highlighted as being of major importance in many countries. One consequence of the ongoing EC review of pesticides may be a reduction in the range of modes of action available to European farmers. This may reduce the opportunities for rotating different modes of action as a method of reducing resistance risk. Greater dependence on high resistance risk herbicides, such as ACCase and ALS inhibitors, because of lack of alternative modes of action, is likely to increase the incidence of resistance in grass-weeds. PMID:15759389

  11. Organic fields sustain weed metacommunity dynamics in farmland landscapes.

    PubMed

    Henckel, Laura; Börger, Luca; Meiss, Helmut; Gaba, Sabrina; Bretagnolle, Vincent

    2015-06-01

    Agro-ecosystems constitute essential habitat for many organisms. Agricultural intensification, however, has caused a strong decline of farmland biodiversity. Organic farming (OF) is often presented as a more biodiversity-friendly practice, but the generality of the beneficial effects of OF is debated as the effects appear often species- and context-dependent, and current research has highlighted the need to quantify the relative effects of local- and landscape-scale management on farmland biodiversity. Yet very few studies have investigated the landscape-level effects of OF; that is to say, how the biodiversity of a field is affected by the presence or density of organically farmed fields in the surrounding landscape. We addressed this issue using the metacommunity framework, with weed species richness in winter wheat within an intensively farmed landscape in France as model system. Controlling for the effects of local and landscape structure, we showed that OF leads to higher local weed diversity and that the presence of OF in the landscape is associated with higher local weed biodiversity also for conventionally farmed fields, and may reach a similar biodiversity level to organic fields in field margins. Based on these results, we derive indications for improving the sustainable management of farming systems. PMID:25994672

  12. Protocols for Robust Herbicide Resistance Testing in Different Weed Species.

    PubMed

    Panozzo, Silvia; Scarabel, Laura; Collavo, Alberto; Sattin, Maurizio

    2015-01-01

    Robust protocols to test putative herbicide resistant weed populations at whole plant level are essential to confirm the resistance status. The presented protocols, based on whole-plant bioassays performed in a greenhouse, can be readily adapted to a wide range of weed species and herbicides through appropriate variants. Seed samples from plants that survived a field herbicide treatment are collected and stored dry at low temperature until used. Germination methods differ according to weed species and seed dormancy type. Seedlings at similar growth stage are transplanted and maintained in the greenhouse under appropriate conditions until plants have reached the right growth stage for herbicide treatment. Accuracy is required to prepare the herbicide solution to avoid unverifiable mistakes. Other critical steps such as the application volume and spray speed are also evaluated. The advantages of this protocol, compared to others based on whole plant bioassays using one herbicide dose, are related to the higher reliability and the possibility of inferring the resistance level. Quicker and less expensive in vivo or in vitro diagnostic screening tests have been proposed (Petri dish bioassays, spectrophotometric tests), but they provide only qualitative information and their widespread use is hindered by the laborious set-up that some species may require. For routine resistance testing, the proposed whole plant bioassay can be applied at only one herbicide dose, so reducing the costs. PMID:26167668

  13. How weeds emerge: a taxonomic and trait-based examination using United States data

    PubMed Central

    Kuester, Adam; Conner, Jeffrey K; Culley, Theresa; Baucom, Regina S

    2014-01-01

    Weeds can cause great economic and ecological harm to ecosystems. Despite their importance, comparisons of the taxonomy and traits of successful weeds often focus on a few specific comparisons – for example, introduced versus native weeds.We used publicly available inventories of US plant species to make comprehensive comparisons of the factors that underlie weediness. We quantitatively examined taxonomy to determine if certain genera are overrepresented by introduced, weedy or herbicide-resistant species, and we compared phenotypic traits of weeds to those of nonweeds, whether introduced or native.We uncovered genera that have more weeds and introduced species than expected by chance and plant families that have more herbicide-resistant species than expected by chance. Certain traits, generally related to fast reproduction, were more likely to be associated with weedy plants regardless of species’ origins. We also found stress tolerance traits associated with either native or introduced weeds compared with native or introduced nonweeds. Weeds and introduced species have significantly smaller genomes than nonweeds and native species.These results support trends for weedy plants reported from other floras, suggest that native and introduced weeds have different stress adaptations, and provide a comprehensive survey of trends across weeds within the USA. PMID:24494694

  14. Effects of nitrogen application method and weed control on corn yield and yield components.

    PubMed

    Sepahvand, Pariya; Sajedi, Nurali; Mousavi, Seyed Karim; Ghiasvand, Mohsen

    2014-04-01

    The effects of nitrogen fertilizer application and different methods for weed control on yield and yield components of corn was evaluated in Khorramabad in 2011. The experiment was conducted as a split plot based on randomized complete block design in 3 replications. Nitrogen application was as main plot in 4 levels (no nitrogen, broadcasting nitrogen, banding nitrogen and sprayed nitrogen) and methods of weed control were in 4 levels (non-control weeds, application Equip herbicide, once hand control of weeds and application Equip herbicide+once time weeding) was as subplots. Result illustrated that effects of nitrogen fertilizer application were significant on grain and forage yield, 100 seeds weight, harvest index, grain number per row and cob weight per plant. Grain yield increased by 91.4 and 3.9% in application banding and broadcasting for nitrogen fertilizer, respectively, compared to the no fertilizer treatment. The results show improved efficiency of nitrogen utilization by banding application. Grain yield, harvest index, seed rows per cob, seeds per row and cob weight were increased by weed control. In the application of Equip herbicide+ hand weeding treatment corn grain yield was increased 126% in comparison to weedy control. It represents of the intense affects of weed competition with corn. The highest corn grain yield (6758 kg h(-1)) was related to the application banding of nitrogen fertilizer and Equip herbicide+once hand weeding. PMID:25911836

  15. Integration of agronomic practices with herbicides for sustainable weed management in aerobic rice.

    PubMed

    Anwar, M P; Juraimi, A S; Mohamed, M T M; Uddin, M K; Samedani, B; Puteh, A; Man, Azmi

    2013-01-01

    Till now, herbicide seems to be a cost effective tool from an agronomic view point to control weeds. But long term efficacy and sustainability issues are the driving forces behind the reconsideration of herbicide dependent weed management strategy in rice. This demands reappearance of physical and cultural management options combined with judicious herbicide application in a more comprehensive and integrated way. Keeping those in mind, some agronomic tools along with different manual weeding and herbicides combinations were evaluated for their weed control efficacy in rice under aerobic soil conditions. Combination of competitive variety, higher seeding rate, and seed priming resulted in more competitive cropping system in favor of rice, which was reflected in lower weed pressure, higher weed control efficiency, and better yield. Most of the herbicides exhibited excellent weed control efficiency. Treatments comprising only herbicides required less cost involvement but produced higher net benefit. On the contrary, treatments comprising both herbicide and manual weeding required high cost involvement and thus produced lower net benefit. Therefore, adoption of competitive rice variety, higher seed rate, and seed priming along with spraying different early-postemergence herbicides in rotation at 10 days after seeding (DAS) followed by a manual weeding at 30 DAS may be recommended from sustainability view point. PMID:24223513

  16. Airborne gamma-ray spectrometer and magnetometer survey: Weed quadrangle, California. Final report

    SciTech Connect

    Not Available

    1981-05-01

    Volume II contains the flight path, radiometric multi-parameter stacked profiles, magnetic and ancillary parameter stacked profiles, histograms, and anomaly maps for the Weed Quadrangle in California.

  17. Host status of six major weeds to Meloidogyne chitwoodi and Pratylenchus penetrans, including a preliminary field survey concerning other weeds

    Microsoft Academic Search

    Vhukile Kutywayo; Thomas H. Been

    2006-01-01

    A glasshouse experiment was carried out to investigate the host status of six important weeds in intensive agricultural cropping systems to Meloidogyne chitwoodi and Pratylenchus penetrans. Senecio vulgaris L., Capsella bursa-pastoris (L.) Medic. and Solanum nigrum L. were hosts of M. chitwoodi with reproduction factors of 2.5, 2.6 and 7.8, respectively. Echinochloa crusgalli (L.) Beauv. and Stellaria media (L.) Vill.

  18. Phytotoxicity of the volatile monoterpene citronellal against some weeds.

    PubMed

    Singh, Harminder Pal; Batish, Daizy R; Kaur, Shalinder; Kohli, Ravinder K; Arora, Komal

    2006-01-01

    A study was undertaken to assess the phytotoxicity of citronellal, an oxygenated monoterpenoid with an aldehyde group, towards some weedy species [Ageratum conyzoides L., Chenopodium album L., Parthenium hysterophorus L., Malvastrum coromandelianum (L.), Garcke, Cassia occidentalis L. and Phalaris minor Retz.]. A significant effect on weed emergence and early seedling growth was observed in a dose-response based laboratory bioassay in a sand culture. Emergence of all test weeds was completely inhibited at 100 micro/g sand content of citronellal. Seeds of A. conyzoides and P. hysterophorus failed to emerge even at 50 microg/g content. Root length was inhibited more compared to shoot length. The failure of root growth was attributed to the effect of citronellal on the mitotic activity of growing root tips cells as ascertained by the onion root tip bioassay. At 2.5 mM treatment of citronellal, mitosis was completely suppressed and at higher concentrations cells showed various degrees of distortion and were even enucleated. The post-emergent application of citronellal also caused visible injury in the form of chlorosis and necrosis, leading to wilting and even death of test weeds. Among the test weeds, the effect was severe on C. album and P. hysterophorus. There was loss of chlorophyll pigment and reduction in cellular respiration upon citronellal treatment indicating the impairment of photosynthetic and respiratory metabolism. Scanning electron microscopic studies in C. occidentalis leaves upon treatment of citronellal revealed disruption of cuticular wax, clogging of stomata and shrinkage of epidermal cells at many places. There was a rapid electrolyte leakage in the leaf tissue upon exposure to citronellal during the initial few hours. In P. minor electrolyte leakage in response to 2 mM citronellal was closer to the maximum leakage that was obtained upon boiling the tissue. The rapid ion leakage is indicative of the severe effect of citronellal on the membrane structure and loss of membrane integrity. In all, the study concludes that citronellal causes a severe phytotoxicity on the weeds. PMID:16869489

  19. Integration of biological control agents with other weed management technologies: Successes from the leafy spurge ( Euphorbia esula) IPM program

    Microsoft Academic Search

    Rodney G. Lym

    2005-01-01

    An invasive weed can occupy a variety of environments and ecological niches and generally no single control method can be used across all areas the weed is found. Biological control agents integrated with other methods can increase and\\/or improve site-specific weed control, but such combinatorial approaches have not been widely utilized. The successful leafy spurge (Euphorbia esula L.) control program

  20. A survey of management and economic impact of weeds in dryland cotton cropping systems of subtropical Australia

    Microsoft Academic Search

    S. R. Walker; I. N. Taylor; G. Milne; V. A. Osten; Z. Hoque; R. J. Farquharson

    2005-01-01

    In dryland cotton cropping systems, the main weeds and effectiveness of management practices were identified, and the economic impact of weeds was estimated using information collected in a postal and a field survey of Southern Queensland and northern New South Wales. Forty-eight completed questionnaires were returned, and 32 paddocks were monitored in early and late summer for weed species and

  1. Floristic composition and abundance of rice?field weeds in four low?country Wet Zone districts of Sri Lanka

    Microsoft Academic Search

    J. P. N. R. Chandrasena

    1988-01-01

    One hundred and thirty six weed species, belonging to twenty nine plant families were recorded from rice weed surveys carried out in four major rice?growing districts of the low country Wet Zone of Sri Lanka, during two consecutive ‘Yala’ seasons in 1984 and 1985. In terms of abundance and distribution Moncotyledon weeds of the Poaceae and Cyperaceae, were found to

  2. Effects of seeding rate and poultry litter on weed suppression from a rolled cereal rye cover crop

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Growing enough cover crop biomass to adequately suppress weeds is one of the primary challenges in reduced-tillage systems that rely on mulch-based weed suppression. We investigated two approaches to increasing cereal rye biomass for improved weed suppression: (1) increasing soil fertility and (2) i...

  3. Application for CALS-CCE 2012 Summer Internship Title of project: Organic weed management for school grounds

    E-print Network

    Keinan, Alon

    Application for CALS-CCE 2012 Summer Internship Title of project: Organic weed management the efficacy of organic herbicides versus thermal removal in controlling weeds prevalent on NYS school landscapes. Thermal weeding refers to equipment that delivers intense bursts of heat on plants. Thermal

  4. Prepared by: BMP Interior and Exterior Weed Control Audit Subcommittee 5/02/07 Interior & Exterior Greenhouse Herbicides

    E-print Network

    Keinan, Alon

    Prepared by: BMP Interior and Exterior Weed Control Audit Subcommittee 5/02/07 Interior & Exterior edible crops in treated soil for 1 year following application When to Use When weeds are actively growing the reproductive stage. Less effective in cool conditions When weeds are actively growing. Works well in cooler

  5. Site-Specific Herbicide Management (SSHM) in Precision Agriculture (PA) requires weed detection in crop fields for

    E-print Network

    Coburn, Craig

    Abstract Site-Specific Herbicide Management (SSHM) in Precision Agriculture (PA) requires weed) for improving crop/weed species discrimination in SSHM/PA. Very high spatial resolution (1.25 mm) ground-based hyperspectral image data were acquired over field plots of canola, pea, and wheat crops seeded with two weed

  6. Maize Dwarf Mosaic Can Reduce Weed Suppressive Ability of Sweet Corn Martin M. Williams II and Jerald K. Pataky*

    E-print Network

    Sims, Gerald K.

    Maize Dwarf Mosaic Can Reduce Weed Suppressive Ability of Sweet Corn Martin M. Williams II prevalent viral disease of sweet corn grown in many regions of North America and Europe. Although some weeds escape control in most sweet corn fields, the extent to which MDM influences the weed suppressive ability

  7. Bradley D. Hanson 2004 Ph.D. Plant Science (Weed Science/Plant Genetics), University of Idaho.

    E-print Network

    Hanson, Brad

    Bradley D. Hanson Education: 2004 Ph.D. Plant Science (Weed Science/Plant Genetics), University of Idaho. 1999 M.S. Plant Science (Weed Science), University of Idaho. 1996 B.S. Agricultural Studies Extension Specialist. University of California, Davis. Statewide weed management research and extension

  8. Effect of Fertilizer Nitrogen on Weed Emergence and Growth Amy E. Sweeney, Karen A. Renner, Carrie Laboski, and Adam Davis*

    E-print Network

    Sims, Gerald K.

    Effect of Fertilizer Nitrogen on Weed Emergence and Growth Amy E. Sweeney, Karen A. Renner, Carrie, emergence, and competitiveness of weeds. Research was conducted to determine the influence of total inorganic soil N (Nit) on the germination, emergence, and growth of five weed species. In a greenhouse

  9. Weed Competition Control in Hardwood Plantations John R. Seifert, Division of Forestry, Indiana Department of Natural Resources

    E-print Network

    Weed Competition Control in Hardwood Plantations FNR-224 John R. Seifert, Division of Forestry and Natural Resources, Purdue University Introduction Controlling or eliminating weed competition-growing herbaceous weeds such as grasses, sedges, and broad-leaved plants or undesired woody perennials such as trees

  10. Weed Management in Pastures and Rangeland -20091 B.A. Sellers and J.A. Ferrell2

    E-print Network

    Jawitz, James W.

    SS-AGR-08 Weed Management in Pastures and Rangeland - 20091 B.A. Sellers and J.A. Ferrell2 1 of County Commissioners Cooperating. Interim Dean Millie Ferrer. Effective weed control begins with good pasture or rangeland management. Weeds are seldom a serious problem in a well managed, vigorously growing

  11. Mario Barco , Attawan Aramrak, Jared Bell and Ian C. Burke Weed Biology-Biotechnology, Washington State University, Pullman, WA

    E-print Network

    Collins, Gary S.

    Mario Barco , Attawan Aramrak, Jared Bell and Ian C. Burke Weed Biology-Biotechnology, Washington State University, Pullman, WA Introduction Weed control is a top priority to growers, conservationists agricultural output and potential land productivity. Herbicides are used extensively to control weed

  12. DOI: 10.1111/j.1365-3180.2012.00915.x Weed interference with field-grown soyabean

    E-print Network

    Sims, Gerald K.

    DOI: 10.1111/j.1365-3180.2012.00915.x Weed interference with field-grown soyabean decreases under, Canada Summary Rising atmospheric [CO2] is predicted to affect C3 and C4 weed interference with crop species differently, with C3 weeds benefiting more from elevated [CO2] (eCO2) than C4 species. Our aim

  13. A molecular weed-mycoherbicide interaction: Colletotrichum gloeosporioides f. sp. malvae and round-leaved mallow, Malva pusilla

    Microsoft Academic Search

    Paul H. Goodwin

    2001-01-01

    Many potential biological control agents of weeds have been found to be hemibiotrophs. One reason for this may be that the period of biotrophic growth in the weed provides a high degree of specificity, whereas the subsequent period of necrotrophic growth results in considerable weed damage or death. An example of a hemibiotrophic mycoherbicide is Colletotrichum gloeosporioides f. sp. malvae

  14. Modeling with Limited Data: The Influence of Crop Rotation and Management on Weed Communities and Crop Yield Loss

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Theory and models of crop yield loss from weed competition have lead to decision models to help growers with cost-effective tactical weed management. Weed management decision models are available for multiple-species populations in a single season of several crops. Growers also rely on crop rotation...

  15. Control of grass, weeds, and brush is an important cultural practice. Before planting a holly orchard, develop

    E-print Network

    Liskiewicz, Maciej

    Control of grass, weeds, and brush is an important cultural practice. Before planting a holly orchard, develop a weed control strategy that will ensure good plant growth at a minimal cost. Reasons will require extensive control. Asparse grass, weed, or clover cover may require no more than a yearly mowing

  16. Those Nasty Weeds Why Not Control Naturally with Livestock? Contributed by Steve Van Vleet, WSU Whitman County Extension Educator

    E-print Network

    Collins, Gary S.

    Those Nasty Weeds ­ Why Not Control Naturally with Livestock? Contributed by Steve Van Vleet, WSU the restricted use of management tools and the prevalence of undesirable plants or weeds that reduce wildlife impacts of herbicides, is causing landowners to seek alternative weed management strategies. One

  17. First report of anthracnose stem Canker of the invasive perennial weed Lepidium draba caused by Colletotrichum higginsianum in Europe

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The exotic perennial Lepidium draba occurs as an invasive weed in dense stands in rangelands and disturbed areas in several states of the western U. S., and as an agricultural weed in the prairie provinces of Canada. To help determine strategies for biological control of the weed such as a potential...

  18. Influence of weed mat and surface sawdust mulch on soil nutrient availability and soil chemical properties under organic blueberry production

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Weed control represents one of the most important cultural management aspects for organic blueberry production. Two of the most common ways to control weeds in blueberries is by the use of surface sawdust mulch or by landscape fabric, often referred to as weed mat. Soil temperature and soil moisture...

  19. Effect of water, tillage and herbicide on ecology of weed communities in intensive wet-seeded rice system

    Microsoft Academic Search

    R. M. Bhager; S. I. Bhuiyan; K. Moody; L. E. Estorninos

    1999-01-01

    Quantitative information on shifts in weed flora brought about by changing soil and water management practices can provide valuable indications for future weed control strategies. This study designed to address quantitative effects on weed ecology as a result of changing water regime, tillage intensity and herbicide dose, was carried out on a farmers field in village Baluga, Talavera, Nueva Ecija,

  20. Weed species diversity and community composition in organic and conventional cropping of spring cereals

    Microsoft Academic Search

    Terho Hyvönen; Elise Ketoja; Jukka Salonen; Heikki Jalli; Juha Tiainen

    2003-01-01

    Interest in organic farming is growing rapidly in Europe. The resulting expansion of the organic farming area has been expected to enhance the biodiversity of agricultural habitats. Organic cropping practices can be hypothesized to support a higher number of weed species than conventional cropping and also to favor herbicide-susceptible and less-nitrophilous species. The diversity and species composition of weed communities

  1. Weed seed predation increases with vegetation cover in perennial forage crops

    Microsoft Academic Search

    Helmut Meiss; Lise Le Lagadec; Nicolas Munier-Jolain; Rainer Waldhardt; Sandrine Petit

    2010-01-01

    Vegetation cover may affect weed seed predation by modifying the habitat quality for predatory organisms. Post-dispersal weed seed predation was measured by placing ‘seed cards’ in two perennial crops (alfalfa, cocksfoot) with and without crop cutting and in plots with bare soil. Each treatment was repeated four times in a randomized complete block design. Vegetation cover was measured by canopy

  2. Assessment of endangered synanthropic plants of Hungary with special attention to arable weeds

    Microsoft Academic Search

    G. Pinke; G. Király; Z. Barina; A. Mesterházy; L. Balogh; J. Csiky; A. Schmotzer; A. V. Molnár; R. W. Pál

    2011-01-01

    In the present study, species were selected from the new Red List of the vascular flora of Hungary which can be regarded as a weed. For each species, current conservation status and the most important traits were assessed. Altogether 149 weed species were found to be at risk according to the International Union for Conservation of Nature (IUCN) categories: 11

  3. PAGMan - propelled abrasive grit to manage weeds in soybean and corn

    Technology Transfer Automated Retrieval System (TEKTRAN)

    New tools for controlling weeds would be useful for soybean and corn production in organic systems or in systems in which weeds developed resistance to multiple herbicides. Here we report on two developments: (i) the safety to soybean seedlings of using air-propelled abrasive grit (PAG) for managing...

  4. Extracting fuzzy rules to describe weed infestations in terms of soil factors

    Microsoft Academic Search

    A. Ribeiro; B. Diaz; M. C. Garcia-Alegre

    2003-01-01

    Site-specific treatment of weeds in precision agriculture is essential to know which factors determine a high occurrence of weeds. Former statistical studies searching for relationships between individual soil variables and wild-oat occurrence found no clear linear relationship among the analyzed variables. However, farmers observations pointed to better wild oats grow in specific locations where the physical and chemical conditions are

  5. Controlling herbicide-resistant weeds: consider incorporating alfalfa in a corn/soybean rotation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Herbicide resistant weeds (HRW) are a serious problem in the U.S. In 1968, the first confirmed case of herbicide resistance in weeds was reported in Washington state. In the 46 years since, the number of HRW in the U.S. has increased dramatically. A major reason for the recent increase in HRW has be...

  6. Impact of precision applications of ammonium nonanoate on weed control efficacy

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Many factors contribute to the successful application of herbicides, including the herbicide’s mode of action, nozzle selection, application rate, application volume, weed species and weed maturity. The precision application of herbicides is especially important to commercial vegetable producers be...

  7. Symposium Long-term weed management studies in the Pacific Northwest

    Microsoft Academic Search

    Frank L. Young

    2004-01-01

    The winter wheat production system of the Pacific Northwest is characterized by severe wind and water erosion and winter annual grass weeds requiring high herbicide input. Since 1985, numerous multi- and interdisciplinary, long-term, large-scale, integrated cropping systems studies have been or are currently being conducted. The primary focus of these studies was on weed biology, ecology, and management, whereas secondary

  8. Living boundaries: tracking weed seed movement with non-dormant seeds

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Synthetic seed banks are a useful tool for increasing precision of counts in weed demography studies. By sowing a known number of seeds of a single accession within a spatially well-described area, an investigator can greatly improve the signal to noise ratio, relative to the ambient weed seed bank,...

  9. Weed Seedbank Composition in a Long-Term Tillage and Landscape Variability Study

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Weed composition has been shown to be influenced by numerous environmental and cropping system attributes. The objective of this study was to evaluate cropping and landscape effects on weed seedbank composition. Soil samples at two depths were collected in fall 2006 from an established experiment ...

  10. Applying molecular-based approaches to classical biological control of weeds John F. Gaskin a,

    E-print Network

    Hufbauer, Ruth A.

    Review Applying molecular-based approaches to classical biological control of weeds John F. Gaskin. This review provides an overview of how to use molecular approaches in biological control of weeds the biology and ecology of agents and their targets and those with skills using molecular approaches. We

  11. Weed-crop competition relationships differ between organic and conventional cropping systems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Organic farmers have identified weed management to be a top research priority and production constraint, as the efficacy of organic weed management is often more variable than conventional herbicide-based methods. The Rodale Institute Farming Systems Trial (FST) provides a unique 27-year history of ...

  12. Weed occurrence in Finnish coastal regions: a survey of organically cropped spring cereals

    Microsoft Academic Search

    Paul Riesinger; Terho Hyvönen

    2006-01-01

    Weed communities of organically cropped spring cereal stands in the southern and the northwestern coast- al regions of Finland (= south and northwest, respectively) were compared with respect to number of spe- cies, frequency of occurrence, density and dry weight. Regional specialization of agricultural production along with differences in climate and soil properties were expected to generate differences in weed

  13. Dalmatian Toadflax, an Invasive Exotic Noxious Weed, Threatens Flagstaff Pennyroyal Community Following Prescribed Fire

    Microsoft Academic Search

    BARBARA GOODRICH PHILLIPS; DEBRA CRISP

    Many noxious weed infestations are initiated or increased by soil disturbance. With the recent emphasis on reintroduction of fire into natural ecosystems there has been increased interest in the effects of noxious weeds following fires. This paper discusses the effects of fire on Flagstaff pennyroyal, a Forest Service Region 3 sensitive plant, and the subsequent infesta- tion of the project

  14. When divergent life histories hybridize: insights into adaptive life-history traits in an annual weed

    E-print Network

    Snow, Allison A.

    Key words: contemporary evolution, crop­wild hybridization, life history, natural selection, Raphanus-stemmed weed, and its late-flowering, large-stemmed, crop relative (Raphanus spp.). Replicate wild and hybrid- tural weed, Raphanus raphanistrum. Crop-to-wild gene flow may serve as a model system to evaluate

  15. The mechanism for weed suppression by a forage radish cover crop

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In the Mid-Atlantic region, forage radish (Raphanus sativus L. var. longipinnatus) winter cover crops planted prior to 1 September suppress winter annual weeds from fall until early April. Little is known about the mechanism of this weed suppression. Published research reports suggest that allelopat...

  16. Experimental Transmission of Pospiviroid Populations to Weed Species Characteristic of Potato and Hop Fields

    Microsoft Academic Search

    J. Matousek; L. Orctova; J. Ptacek; J. Patzak; P. Dedic; G. Steger; D. Riesner

    2007-01-01

    Weed plants characteristic for potato and hop fields have not been considered in the past as potential hosts that could transmit and lead to spreading of potato spindle tuber (PSTVd) and hop stunt (HSVd) viroids, respectively. To gain insight into this problem, we biolistically inoculated these weed plants with viroid populations either as RNA or as cDNA. New potential viroid

  17. HERBICIDES-WEEDS: A PRACTICAL APPROACH TO RESISTANCE MANAGEMENT IN POTATO CROPPING SYSTEMS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Herbicides exert a selection pressure on weed populations and weeds that are not controlled may produce seed and give rise to progeny with genetic resistance to the herbicide. Herbicide classification systems based on site/mode of action have been developed and knowing a herbicide’s mode/site of ac...

  18. Effect of Seeding Rate and Planting Arrangement on Rye Cover Crop and Weed Growth

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Weed growth in winter cover crops in warm climates may contribute to weed management costs in subsequent crops. A two year experiment was conducted on an organic vegetable farm in Salinas, California, to determine the impact of seeding rate and planting arrangement on rye (Secale cereale L. cv. Merc...

  19. WEED HOSTS OF PARATRICHODORUS ALLIUS AND TOBACCO RATTLE VIRUS IN THE PACIFIC NORTHWEST

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The ability of several weed species to serve as hosts for tobacco rattle virus (TRV), the causal agent of corky ringspot disease of potato (CRS), and its nematode vector, Paratrichodorus allius, was investigated in greenhouse studies. Viruliferous P. allius multiplied on 24 out of 37 weed species t...

  20. Technology Transfer Programs for Biological Control of Weeds — the New Zealand Experience

    Microsoft Academic Search

    L. M. HAYES

    Biological control has become a major focus for managing a variety of agricultural and conservation weeds in New Zealand. For nearly 2 decades Landcare Research (for- merly DSIR) has operated successful technology transfer programs with most organiza- tions that manage weeds in New Zealand. Program success is based on strong relation- ships built up between Landcare Research and participating organizations