Weed Control and Herbicide Tolerance in a Common Vetch-Oat Intercrop

Field studies were conducted over 3 yr in central Spain to investigate the tolerance of common vetch and oat to some preemergence herbicides and their effects on weed control, forage yields, and botanical composition of the forage mixture. Pendimethalin was the only herbicide that injured common vetch. Pronamide and pronamide plus diuron injured oat by affecting plant emergence. Prevalent weed species were fumitory, henbit, and wild buckwheat. All herbicides provided more than 90% control of fumitory and most herbicides except pronamide provided more than 90% control of henbit relative to the untreated check. Wild buckwheat stands were reduced by isoxaben (68%), linuron (40%), prometryn (69%), pronamide (86%), and pronamide plus diuron (61%). More than 90% control of prostrate knotweed was achieved with isoxaben, pronamide, and terbutryn. Pronamide and pronamide plus diuron reduced forage yields and increased vetch in the forage. The untreated vetch and oat monocrop treatments showed the competitive advantage of oat over vetch and weedy species.

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Weed Control for Pot-In-Pot Production using Preemergence Herbicides

Journal of Environmental Horticulture ◽

10.24266/0738-2898-23.4.204 ◽

2005 ◽

Vol 23 (4) ◽

pp. 204-211

Author(s):

Donna C. Fare ◽

Patricia Knight ◽

Charles H. Gilliam ◽

James Altland

Keyword(s):

Weed Control ◽

Acer Rubrum ◽

Herbicide Tolerance ◽

Green Ash ◽

Red Maple ◽

Weed Species ◽

Magnolia Grandiflora ◽

Pyrus Calleryana ◽

Local Site ◽

Preemergence Herbicides

Abstract Four experiments were conducted to investigate herbicides currently labeled for field and/or container production for use in pot-in-pot production. Southern magnolia (Magnolia grandiflora L.), red maple (Acer rubrum Spach. ‘Autumn Flame’ and ‘Franksred’), ornamental pear (Pyrus calleryana Decne. ‘Bradford’ and ‘Cleveland Select’), river birch (Betula nigra L.), green ash (Fraxinus pennsylvanica Marsh. and F. pennsylvanica Marsh.‘Marshall's Seedless’), and zelkova (Zelkova serrata Spach ‘Village Green’) were evaluated for herbicide tolerance. Barricade 65WG, Surflan 4AS, and Pendulum 60WDG, used alone or in combination with Princep and Gallery 75 DF, had no adverse effect on tree shoot growth or trunk caliper growth when applied as a directed band application. Weed control varied depending upon local site conditions, herbicide rate and weed species.

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Establishing white clover (Trifolium repens) as a living mulch: weed control and herbicide tolerance

Weed Technology ◽

10.1017/wet.2021.45 ◽

2021 ◽

pp. 1-28

Author(s):

Nicholas T. Basinger ◽

Nicholas S. Hill

Keyword(s):

Weed Control ◽

White Clover ◽

Cover Crops ◽

Herbicide Tolerance ◽

Single Application ◽

Weed Species ◽

Living Mulch ◽

Herbicide Resistant ◽

Research And Education ◽

Weed Emergence

Abstract With the increasing focus on herbicide-resistant weeds and the lack of introduction of new modes of action, many producers have turned to annual cover crops as a tool for reducing weed populations. Recent studies have suggested that perennial cover crops such as white clover could be used as living mulch. However, white clover is slow to establish and is susceptible to competition from winter weeds. Therefore, the objective of this study was to determine clover tolerance and weed control in established stands of white clover to several herbicides. Studies were conducted in the fall and winter of 2018 to 2019 and 2019 to 2020 at the J. Phil Campbell Research and Education Center in Watkinsville, GA, and the Southeast Georgia Research and Education Center in Midville, GA. POST applications of imazethapyr, bentazon, or flumetsulam at low and high rates, or in combination with 2,4-D and 2,4-DB, were applied when clover reached 2 to 3 trifoliate stage. Six weeks after the initial POST application, a sequential application of bentazon and flumetsulam individually, and combinations of 2,4-D, 2,4-DB, and flumetsulam were applied over designated plots. Clover biomass was similar across all treatments except where it was reduced by sequential applications of 2,4-D + 2,4-DB + flumetsulam in the 2019 to 2020 season indicating that most treatments were safe for use on establishing living mulch clover. A single application of flumetsulam at the low rate or a single application of 2,4-D + 2,4-DB provided the greatest control of all weed species while minimizing clover injury when compared to the non-treated check. These herbicide options allow for control of problematic winter weeds during clover establishment, maximizing clover biomass and limiting canopy gaps that would allow for summer weed emergence.

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Absorption, Translocation, and Phytotoxicity of Chlorimuron and 2,4-Db Mixtures in Peanut (Arachis Hypogaea) and Selected Weed Species

Weed Science ◽

10.1017/s0043174500052048 ◽

1993 ◽

Vol 41 (3) ◽

pp. 347-352 ◽

Cited By ~ 3

Author(s):

Glenn R. Wehtje ◽

John W. Wilcut ◽

John A. Mcguire

Keyword(s):

Weed Control ◽

Arachis Hypogaea ◽

Field Studies ◽

The Other ◽

Weed Species ◽

Greenhouse Experiments ◽

Crop Injury ◽

Treated Leaf ◽

Better Than

Mixtures of chlorimuron and 2,4-DB were additive with respect to crop injury and were either additive or slightly antagonistic with respect to weed control in greenhouse experiments. Absorption and translocation of14C following application of14C-chlorimuron and14C-2,4-DB were not affected by the presence of the other unlabeled herbicide, except in Florida beggarweed and peanut where 2,4-DB affected distribution of14C-chlorimuron in the treated leaf. In field studies, maximum efficacy was obtained with mixtures of chlorimuron plus 2,4-DB applied 7 or 9 wk after planting. Florida beggarweed control was greatest with chlorimuron or chlorimuron mixtures while the addition of 2,4-DB to chlorimuron improved morningglory and sicklepod control. At 9 and 11 wk after planting, addition of 2,4-DB to chlorimuron controlled Florida beggarweed better than chlorimuron alone. Peanut yields were increased by the addition of 2,4-DB at later applications.

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Influence of Herbicides and Timing of Application on Broadleaf Weed Control in Peanut (Arachis hypogaea)

Weed Technology ◽

10.1017/s0890037x0004330x ◽

1997 ◽

Vol 11 (4) ◽

pp. 708-713 ◽

Cited By ~ 20

Author(s):

W. James Grichar

Keyword(s):

Weed Control ◽

Arachis Hypogaea ◽

Field Studies ◽

Application Timing ◽

Pitted Morningglory ◽

Untreated Check ◽

Ac 263,222

Field studies were conducted from 1992 through 1994 to evaluate application timing of seven postemergence (POST) broadleaf herbicides alone and in mixtures for control of eclipta and pitted morningglory. Imazethapyr and 2,4-DB did not control eclipta while AC 263,222 applied early postemergence (EPOST) at 0.07 kg/ha provided greater than 90% control in 2 of 3 yr. EPOST applications of bentazon, acifluorfen + bentazon, and pyridate controlled eclipta at least 92% all 3 yr. Lactofen applied EPOST at 0.28 kg/ha provided similar levels of eclipta control in 2 of 3 yr. Imazethapyr controlled pitted morningglory > 70% when applied EPOST. AC 263,222 controlled pitted morningglory a minimum of 83% when applied EPOST at 0.04 or 0.07 kg/ha. Pitted morningglory control was at least 85% with 2,4-DB applied alone or in a mixture with AC 263,222, acifluorfen, imazethapyr, lactofen, or pyridate. Effective weed control increased peanut yields up to 98% over the untreated check.

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Evaluation of sequential applications of quizalofop-P-ethyl and florpyrauxifen-benzyl in acetyl CoA carboxylase-resistant rice

Weed Technology ◽

10.1017/wet.2020.114 ◽

2020 ◽

pp. 1-5

Author(s):

Tameka L. Sanders ◽

Jason A. Bond ◽

Benjamin H. Lawrence ◽

Bobby R. Golden ◽

Thomas W. Allen ◽

...

Keyword(s):

Weed Control ◽

Rice Yield ◽

Field Studies ◽

Growth Stages ◽

Acetyl Coa Carboxylase ◽

Weed Species ◽

Rough Rice ◽

Sequential Treatments ◽

Acetyl Coenzyme A Carboxylase ◽

Grass Weed

Abstract Information on performance of sequential treatments of quizalofop-P-ethyl with florpyrauxifen-benzyl on rice is lacking. Field studies were conducted in 2017 and 2018 in Stoneville, MS, to evaluate sequential timings of quizalofop-P-ethyl with florpyrauxifen-benzyl included in preflood treatments of rice. Quizalofop-P-ethyl treatments were no quizalofop-P-ethyl; sequential applications of quizalofop-P-ethyl at 120 g ha−1 followed by (fb) 120 g ai ha−1 applied to rice in the 2- to 3-leaf (EPOST) fb the 4-leaf to 1-tiller (LPOST) growth stages or LPOST fb 10 d after flooding (PTFLD); quizalofop-P-ethyl at 100 g ha−1 fb 139 g ha−1 EPOST fb LPOST or LPOST fb PTFLD; quizalofop-P-ethyl at 139 g ha−1 fb 100 g ha−1 EPOST fb LPOST and LPOST fb PTFLD; and quizalofop-P-ethyl at 85 g ha−1 fb 77 g ha−1 fb 77 g ha−1 EPOST fb LPOST fb PTFLD. Quizalofop-P-ethyl was applied alone and in mixture with florpyrauxifen-benzyl at 29 g ai ha−1 LPOST. Visible rice injury 14 d after PTFLD (DA-PTFLD) was no more than 3%. Visible control of volunteer rice (‘CL151’ and ‘Rex’) 7 DA-PTFLD was similar and at least 95% for each quizalofop-P-ethyl treatment. Barnyardgrass control with quizalofop-P-ethyl at 120 fb 120 g ha−1 LPOST fb PTFLD was greater (88%) in mixture with florpyrauxifen-benzyl. The addition of florpyrauxifen-benzyl to quizalofop-P-ethyl increased rough rice yield when quizalofop-P-ethyl was applied at 100 g ha−1 fb 139 g ha−1 EPOST fb LPOST. Sequential applications of quizalofop-P-ethyl at 120 g ha−1 fb 120 g ha−1 EPOST fb LPOST, 100 g ha−1 fb 139 g ha−1 EPOST fb LPOST, or 139 g ha−1 fb 100 g ha−1 EPOST fb LPOST controlled grass weed species. The addition of florpyrauxifen-benzyl was not beneficial for grass weed control. However, because quizalofop-P-ethyl does not control broadleaf weeds, florpyrauxifen-benzyl could provide broad-spectrum weed control in acetyl coenzyme A carboxylase–resistant rice.

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Weed management with CGA-362622 in transgenic and nontransgenic cotton

Weed Science ◽

10.1614/p2002-014 ◽

2003 ◽

Vol 51 (6) ◽

pp. 1002-1009 ◽

Cited By ~ 19

Author(s):

Dunk Porterfield ◽

John W. Wilcut ◽

Jerry W. Wells ◽

Scott B. Clewis

Keyword(s):

North Carolina ◽

Weed Control ◽

Weed Management ◽

Field Studies ◽

Palmer Amaranth ◽

Management Systems ◽

Weed Species ◽

Crop Tolerance ◽

Prickly Sida ◽

Smooth Pigweed

Field studies conducted at three locations in North Carolina in 1998 and 1999 evaluated crop tolerance, weed control, and yield with CGA-362622 alone and in combination with various weed management systems in transgenic and nontransgenic cotton systems. The herbicide systems used bromoxynil, CGA-362622, glyphosate, and pyrithiobac applied alone early postemergence (EPOST) or mixtures of CGA-362622 plus bromoxynil, glyphosate, or pyrithiobac applied EPOST. Trifluralin preplant incorporated followed by (fb) fluometuron preemergence (PRE) alone or fb a late POST–directed (LAYBY) treatment of prometryn plus MSMA controlled all the weed species present less than 90%. Herbicide systems that included soil-applied and LAYBY herbicides plus glyphosate EPOST or mixtures of CGA-362622 EPOST plus bromoxynil, glyphosate, or pyrithiobac controlled broadleaf signalgrass, entireleaf morningglory, large crabgrass, Palmer amaranth, prickly sida, sicklepod, and smooth pigweed at least 90%. Only cotton treated with these herbicide systems yielded equivalent to the weed-free check for each cultivar. Bromoxynil systems did not control Palmer amaranth and sicklepod, pyrithiobac systems did not control sicklepod, and CGA-362622 systems did not control prickly sida.

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Castor (Ricinus communisL.) Tolerance to Postemergence Herbicides and Weed Control Efficacy

International Journal of Agronomy ◽

10.1155/2012/832749 ◽

2012 ◽

Vol 2012 ◽

pp. 1-5 ◽

Cited By ~ 3

Author(s):

W. James Grichar ◽

Peter A. Dotray ◽

Calvin L. Trostle

Keyword(s):

Weed Control ◽

Cucumis Melo ◽

Field Studies ◽

Control Efficacy ◽

Untreated Check ◽

Postemergence Herbicides

Potential US castor production is limited due to only one labeled herbicide (trifluralin). Field studies were conducted at two Texas locations during 2008 and 2009 to evaluate postemergence herbicides for castor tolerance and weed control efficacy. Clethodim and fluazifop-P-butyl caused no castor stunting while acifluorfen, bentazon, imazethapyr, and lactofen caused stunting which ranged from 5 to 46%. Imazapic and 2,4-DB caused the greatest stunting (44 to 99%) and resulted in castor yields of 0 to 45% of the untreated check. Acifluorfen, imazapic, imazethapyr, lactofen, and 2,4-DB controlled at least 80% smellmelon (Cucumis meloL. var. Dudaim Naud.) while clethodim and fluazifop-P-butyl controlled at least 98% Texas millet [Urochloa texana(Buckl.) R.Webster]. Imazapic and imazethapyr provided 57 to 75% Texas millet control. Results suggest that castor tolerance to the graminicides, clethodim, and fluazifop-P-butyl is high; however, castor injury and yield reductions with the postemergence applications of broadleaf herbicides suggest that these herbicides should not be used in castor production.

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The Effect of Composted Organic Wastes on Weed Control Provided by Preemergence Herbicides

HortScience ◽

10.21273/hortsci.32.3.470e ◽

1997 ◽

Vol 32 (3) ◽

pp. 470E-470

Author(s):

Jennifer A. Johnson ◽

Larry Kuhns ◽

Tracey Harpster

Keyword(s):

Organic Matter ◽

Sewage Sludge ◽

Weed Control ◽

Dry Weight ◽

Field Studies ◽

Silty Clay ◽

Yard Waste ◽

Application Rates ◽

Preemergence Herbicides ◽

Composted Sewage Sludge

Community waste management programs that include the composting of sewage sludge and yard wastes have become a necessity. Using these composts provides many benefits; however, increased levels of organic matter may reduce the effectiveness of preemergence herbicides. Determining how herbicide application rates may need to be adjusted when composted waste is incorporated into the soil may permit the use of these amendments without any decrease in weed control. This experiment examined the effect of two types of compost (composted sewage sludge and composted yard waste) on the weed control provided by four preemergence herbicides. The soil was a Hagerstown silt loam amended with 10%, 20%, or 30% compost by volume. Each mix was placed in half-gallon cardboard milk cartons. The cartons were seeded at 1/2 and 1/4 inches with a mixture of broadleaved weeds and grasses. Each soil mix was treated with simazine, oxyfluorfen, oryzalin, and metolachlor at two rates. Control was evaluated both visually by number and by the dry weight of the harvested weeds. Preliminary results indicate composted sewage sludge causes a greater reduction in herbicide efficacy than composted yard waste. Oryzalin and metolachlor were affected less than oxyfluorfen or simazine. The experiment was repeated using lower application rates. In one replication the soil mixes from the previous experiment were used. The second replication used a Hagerstown silty clay loam soil with fresh compost. The results of this experiment will provide preliminary information for future field studies designed to determine if the application rates of preemergence herbicides need to be adjusted when fields are amended with composted organic matter.

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WEED INTERFERENCE AND WEED PROBLEMS IN LOUISIANA SWEETPOTATOES—A REVIEW

HortScience ◽

10.21273/hortsci.31.5.761b ◽

1996 ◽

Vol 31 (5) ◽

pp. 761b-761

Author(s):

Wayne C. Porter

Keyword(s):

Soil Erosion ◽

Weed Control ◽

Current Problem ◽

Morning Glory ◽

Annual Rainfall ◽

Weed Species ◽

Purple Nutsedge ◽

Weed Interference ◽

Prickly Sida ◽

Preemergence Herbicides

High annual rainfall and frequent torrential deluges have always made weed control a tenuous affair in Louisiana. Herbicide leaching and soil erosion often take preemergence herbicides to the nether regions. Before the time of postemergent grass herbicides, frequent cultivation was the only method to try to salvage the sweetpotato crop when preemergence weed control was lost. For many years, the most serious weed problems were prickly sida, cocklebur, and purple nutsedge with occasional hotspots of morning-glory. However, due to the change in herbicides used, the species of problem weeds have shifted to rice flatsedge, yellow and purple nutsedge, carpetweed, and various pigweeds. Before the registration of Command herbicide for use in sweetpotatoes, many sweetpotato growers used herbicides that effectively controlled or suppressed the current problem weeds. With the widespread use of Command, prior problem weed species are effectively controlled, but these other problem weeds are released.

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Mefluidide as an Enhancing Agent for Postemergence Broadleaf Herbicides in Soybeans (Glycine max)

Weed Technology ◽

10.1017/s0890037x00029353 ◽

1987 ◽

Vol 1 (2) ◽

pp. 149-153 ◽

Cited By ~ 1

Author(s):

Michael R. Blumhorst ◽

George Kapusta

Keyword(s):

Glycine Max ◽

Weed Control ◽

Field Studies ◽

Weed Species ◽

Nitrobenzoic Acid ◽

Petroleum Oil

In field studies, mefluidide {N-[2,4-dimethyl-5-[[(trifluoromethyl)sulfonyl] amino] phenyl] acetamide} was most effective as an enhancing agent for bentazon [3-(1-methylethyl)-(1H)-2,1,3-benzothiadiazin-4(3H)-one 2,2-dioxide] and/or acifluorfen {5-[2-chloro-4-(trifluoromethyl)phenoxy]-2-nitrobenzoic acid} when applied as a tank mixture compared to sequential applications. The influence of mefluidide rate on weed control was not consistent. Additives improved the control of several weed species evaluated, but mefluidide generally was only equal to petroleum oil concentrate (phytobland petroleum oil plus emulsifiers in an 83:17 ratio) as an enhancing agent for bentazon and/or acifluorfen.

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