Browsing by Author "Bradley, Kevin Wayne"

Now showing 1 - 12 of 12
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    Characterization of the Mechanism of Resistance of a Johnsongrass (Sorghum halepense) Biotype to Selected Graminicides in Virginia and Response of Mugwort (Artemisia vulgaris) to Specific Herbicidal and Cultural Control Strategies
    Bradley, Kevin Wayne (Virginia Tech, 2000-04-26)
    Johnsongrass [Sorghum halepense (L.) Pers.] and mugwort (Artemisia vulgaris L.) are both rhizomatous perennial weeds that are capable of rapidly colonizing a variety of different environments. Separate experiments were conducted throughout Virginia from 1996 to 1999 to determine more effective methods for reducing infestations of these perennial weeds in the future. Field and greenhouse experiments conducted on a resistant johnsongrass population discovered in New Kent County, Virginia revealed that this biotype exhibits low levels of resistance to the aryloxyphenoxypropionate (APP) herbicides quizalofop-P and fluazifop-P and the cyclohexanedione (CHD) herbicide sethoxydim. Additional laboratory experiments revealed that resistance is not due to differential absorption, translocation, or metabolism of the APP and CHD herbicides in the resistant vs. the susceptible biotype. However, acetyl-coenzyme A carboxylase (ACCase) assays revealed that resistance to the APP and CHD herbicides is conferred by an overproduction of the ACCase enzyme in the resistant compared to the susceptible johnsongrass biotype. In field experiments conducted on mugwort infestations discovered in several counties throughout Virginia, 100% mugwort control was achieved with standard application rates of picloram at 4 months after treatment (MAT), and also greater than 70% mugwort control was achieved with the higher application rates of clopyralid, glyphosate, and dicamba at 4 MAT. However, all other herbicides evaluated in these experiments provided less than 65% mugwort control at 4 MAT, even at exceptionally high use rates. Additionally, the results from these trials revealed that sequential herbicide applications and sequential mowings prior to herbicide application are both effective mugwort control strategies.
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    Control of Common Pasture and Hayfield Weeds in Virginia and West Virginia
    King, Steve Russell; Chandran, Rakesh S.; Hagood, Edward S.; Bradley, Kevin Wayne; Love, Kenner; Heidel, Richard D. (Virginia Cooperative Extension, 2009-05-01)
    This publication will discuss control measures for many of the common weeds found in Virginia and West Virginia permanent fescue and mixed fescue, bluegrass, orchardgrass pastures and hayfields. In mixed grass, legume pastures and hayfields, selective removal of many problematic weed species is often not possible as most legumes will be killed after applications of broadleaf herbicides.
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    Fine Tuning a Sprayer with "Ounce" Calibration Method
    Grisso, Robert D.; Weaver, Michael John; Bradley, Kevin Wayne; Hagood, Edward S.; Wilson, Henry P. (Virginia Cooperative Extension, 2009-05-01)
    Guidelines to quickly evaluate the performance of a sprayer. Sprayer calibration, nozzle discharge, spray pattern uniformity, speed checks, pump performance and plumbing arrangements are evaluated with minimal calculations.
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    Fine tuning a sprayer with ounce calibration method
    Grisso, Robert D.; Weaver, Michael John; Bradley, Kevin Wayne; Hagood, Edward S.; Wilson, Henry P. (Virginia Cooperative Extension, 2001)
    This extension publication discusses guidelines to quickly evaluate the performance of a sprayer. Sprayer calibration, nozzle discharge, spray pattern uniformity, speed checks, pump performance and plumbing arrangements are evaluated with minimal calculations.
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    Identification and Control of Annual Ryegrass in No-Till Corn in Virginia
    King, Steve Russell; Hagood, Edward S.; Bradley, Kevin Wayne (Virginia Cooperative Extension, 2009-05-01)
    This publication reviews the identification and control of annual ryegrass in no-till corn in Virginia.
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    Identification and Control of Hemp Dogbane (Apocynum cannabinum L.) in Virginia
    Bradley, Kevin Wayne; Hagood, Edward S. (Virginia Cooperative Extension, 2009-05-01)
    This publication reviews the identification and control of Hemp Dogbane (Apocynum cannabinum L.) in Virginia.
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    Identification and Control of Honeyvine Milkweed (Ampelamus albidus (Nutt.) Britt.) in Virginia
    Bradley, Kevin Wayne; Davis, Paul H.; Hagood, Edward S. (Virginia Cooperative Extension, 2009-05-01)
    This publication reviews the identification and control of Honeyvine Milkweed (Ampelamus albidus) in Virginia.
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    Identification and Control of Horsenettle (Solanum carolinense L.) in Virginia
    Bradley, Kevin Wayne; Hagood, Edward S. (Virginia Cooperative Extension, 2009-05-01)
    This publication reviews the identification and control of Horsenettle (Solanum carolinense) in Virginia.
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    Identification and Control of Mugwort (Artemisia vulgaris L.) in Virginia
    Bradley, Kevin Wayne; Hagood, Edward S. (Virginia Cooperative Extension, 2009-05-01)
    This publication reviews the identification and control of Mugwort (Artemisia vulgaris) in Virginia.
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    Identification and Control of Trumpetcreeper (Campsis radicans (L.) Seem ex Bureau) in Virginia
    Bradley, Kevin Wayne; Hagood, Edward S. (Virginia Cooperative Extension, 2009-05-01)
    This publication reviews the identification and control of Trumpetcreeper (Campsis radicans) in Virginia.
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    Plumbing systems of agricultural sprayers
    Grisso, Robert D.; Weaver, Michael John; Bradley, Kevin Wayne; Hagood, Edward S.; Wilson, Henry P. (Virginia Cooperative Extension, 2009-05-01)
    Care and operation of different varieties of the plumbing systems of agricultural sprayers.
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    Plumbing systems of agricultural sprayers
    Grisso, Robert D.; Weaver, Michael John; Bradley, Kevin Wayne; Hagood, Edward S.; Wilson, Henry P. (Virginia Cooperative Extension, 2001)
    The plumbing systems of agricultural sprayers are usually considered foolproof. Sprayer problems may occur if plumbing and/or modifications are improperly done or maintenance is ignored. Retrofitting, addition of electrical control systems, and replacement of pumps or nozzles require proper knowledge of the plumbing system and the implications of these changes to sprayer performance. Routine maintenance of the plumbing system is essential.