Comparison of Preemergence and Postemergence Weed Control Systems in Newly Established Pecan

Six weed control programs with and without irrigation were investigated in a newly established pecan orchard. Irrigation increased crown diameter growth in only one of seven growing seasons but increased nut yield an average of 35% in the first two bearing years. Weed control program significantly influenced crown diameter beginning in the fourth growing season and continued through season six while also impacting final crown diameter. The use of postemergence (POST) herbicides increased crown diameter a minimum 4 mm vs. preemergence (PRE) herbicides. Mowing neither increased nor decreased crown diameter when used with herbicides; however, when used solely, crown diameter was 29% less. Highest growth rates were obtained with a combination PRE plus POST weed management system. Nut yields were closely linked to growth data. No differences in nut yield were observed between PRE- or POST-herbicide programs alone or in combination with mowing. Mowing alone decreased nut yield 57% vs. herbicide-based approaches. A combination PRE- plus POST-weed control program increased yield 38% vs. all other treatments.

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Annual weed management in isoxaflutole-resistant soybean using a two-pass weed control strategy

Weed Technology ◽

10.1017/wet.2019.21 ◽

2019 ◽

Vol 33 (03) ◽

pp. 411-425

Author(s):

Andrea Smith ◽

Nader Soltani ◽

Allan J. Kaastra ◽

David C. Hooker ◽

Darren E. Robinson ◽

...

Keyword(s):

Weed Control ◽

Weed Management ◽

Field Experiments ◽

High Rate ◽

Grass Species ◽

Annual Grass ◽

Common Lambsquarters ◽

Control Programs ◽

The One ◽

Herbicide Programs

AbstractTransgenic crops are being developed with herbicide resistance traits to expand innovative weed management solutions for crop producers. Soybean with traits that confer resistance to the hydroxyphenylpyruvate dioxygenase herbicide isoxaflutole is under development and will provide a novel herbicide mode of action for weed management in soybean. Ten field experiments were conducted over 2 years (2017 and 2018) on five soil textures with isoxaflutole-resistant soybean to evaluate annual weed control using one- and two-pass herbicide programs. The one-pass weed control programs included isoxaflutole plus metribuzin, applied PRE, at a low rate (52.5 + 210 g ai ha−1), medium rate (79 + 316 g ai ha−1), and high rate (105 + 420 g ai ha−1); and glyphosate applied early postemergence (EPOST) or late postemergence (LPOST). The two-pass weed control programs included isoxaflutole plus metribuzin, applied PRE, followed by glyphosate applied LPOST, and glyphosate applied EPOST followed by LPOST. At 4 weeks after the LPOST application, control of common lambsquarters, pigweed species, common ragweed, and velvetleaf was variable at 25% to 69%, 49% to 86%, and 71% to 95% at the low, medium, and high rates of isoxaflutole plus metribuzin, respectively. Isoxaflutole plus metribuzin at the low, medium, and high rates controlled grass species evaluated (i.e., barnyardgrass, foxtail, crabgrass, and witchgrass) 85% to 97%, 75% to 99%, and 86% to 100%, respectively. All two-pass weed management programs provided 98% to 100% control of all species. Weed control improved as the rate of isoxaflutole plus metribuzin increased. Two-pass programs provided excellent, full-season annual grass and broadleaf weed control in isoxaflutole-resistant soybean.

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Herbicide reduction in metribuzin-based weed control programs in corn

Canadian Journal of Plant Science ◽

10.4141/cjps95-156 ◽

1995 ◽

Vol 75 (4) ◽

pp. 927-933 ◽

Cited By ~ 12

Author(s):

Allan S. Hamill ◽

Jianhua Zhang

Keyword(s):

Weed Control ◽

Weed Management ◽

Management Practice ◽

Relative Effectiveness ◽

Development Stage ◽

Corn Yield ◽

Economic Return ◽

Control Programs ◽

Field Corn ◽

Herbicide Programs

The relative effectiveness of 13 metribuzin-based weed control programs in field corn was investigated in a 3-yr study. Reduction in herbicide rates was made by modifying some commonly used metribuzin-based herbicide programs for weed control in corn. Satisfactory weed control, corn yield and economic return were obtained under each herbicide treatment, suggesting that reduction in herbicide use to reduce environmental hazard and enhance the economical benefit is achievable. Among the various herbicide programs, banded herbicide application at reduced rates plus one cultivation was observed to be the most economic weed management practice. Herbicides applied early (2–3 leaves) showed better results than those applied later (6–7 leaves) in the development stage of corn, although both times of application are within the critical period of weed control for corn. Key words: Corn (Zea mays), economic return, herbicides, weed control

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Evaluation of Season-Long Weed Management Programs in Red Beet

Weed Technology ◽

10.1614/wt-d-16-00015.1 ◽

2016 ◽

Vol 30 (4) ◽

pp. 898-909 ◽

Cited By ~ 1

Author(s):

Jed B. Colquhoun ◽

Daniel J. Heider ◽

Richard A. Rittmeyer

Keyword(s):

Weed Control ◽

Crop Yield ◽

Broad Spectrum ◽

Weed Management ◽

Soil Type ◽

Injury Risk ◽

Growth Stage ◽

Growing Seasons ◽

Red Beet ◽

Herbicide Programs

Red beet growers have expressed interest in adopting the microrate herbicide approach originally implemented in sugarbeet to achieve season-long weed management. Several red beet herbicides were first labeled for use in sugarbeet and lack substantial residual weed control. In response, red beet herbicide programs were evaluated that included a PRE application followed by up to three POST applications of various herbicide combinations. This research, however, indicated that herbicide programs that included PRE herbicides followed by as few as one or two POST applications that involve multiple active ingredients can provide season-long weed control. This observation was consistent across a broad spectrum of weeds, between two study locations that varied in soil type, and during two growing seasons. Herbicide programs that included only a PRE and six-leaf red beet growth stage application were successful at two locations in maintaining weed control and crop yield relative to hand-weeded red beet. Furthermore, these herbicide programs reduced the number of applications by 50% compared with the full programs, reducing crop injury risk and grower cost.

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Weed Control and Economics in Nontransgenic and Glyphosate-Resistant Soybean (Glycine max)

Weed Technology ◽

10.1017/s0890037x00046248 ◽

1999 ◽

Vol 13 (3) ◽

pp. 586-593 ◽

Cited By ~ 29

Author(s):

Eric P. Webster ◽

Kelly J. Bryant ◽

Larry D. Earnest

Keyword(s):

Glycine Max ◽

Weed Control ◽

Production Systems ◽

Control Program ◽

Roundup Ready ◽

Ipomoea Lacunosa ◽

Control Programs ◽

Net Returns ◽

Herbicide Treatments ◽

Herbicide Programs

A study was conducted in 1996 and 1997 near Rohwer, AR, to evaluate weed control with standard herbicide programs in nontransgenic and glyphosate-resistant soybean (Glycine max) compared with glyphosate-based herbicide programs in glyphosate-resistant soybean. Total postemergence (POST) programs containing 0.84 kg ae/ha glyphosate 14 d after emergence (DAE) followed by 0.42 kg/ha at 42 DAE controlled pitted and entireleaf morningglory (Ipomoea lacunosaandI. hederaceavar.integriuscula) 80 to 83%. This control was lower than with any other weed control program in the study. All glyphosate containing herbicide programs controlled barnyardgrass (Echinochloa crus-galli) at least 94%. Soybean injury was 8% or less for all herbicide treatments except for ‘Hartz 5088 Roundup Ready’ treated with pendimethalin plus chlorimuron and metribuzin preplant incorporated (PPI) followed by glyphosate or acifluorfen plus bentazon 42 DAE. All weed control and soybean injury ratings were similar at 24 d after the 42 DAE application (DAA) when compared with the 10 DAA rating. Two weed control programs with ‘Northrup King S-59-60’ soybean using standard herbicide programs yielded 3,015 and 3,070 kg/ha, and net returns were $92.20/ha and $122.82/ha, respectively. Two production systems containing the Hartz 5088 Roundup Ready cultivar had positive net returns of $35.11/ha and $39.49/ha.

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Smallseed Falseflax (Camelina microcarpa) Management in Oklahoma Winter Wheat

Weed Technology ◽

10.1017/wet.2021.51 ◽

2021 ◽

pp. 1-14

Author(s):

Jodie A. Crose ◽

Misha R. Manuchehri ◽

Todd A. Baughman

Keyword(s):

Winter Wheat ◽

Weed Control ◽

Herbicide Resistance ◽

Wheat Yield ◽

Acetolactate Synthase ◽

Growing Season ◽

Time Of Application ◽

Adequate Control ◽

Growing Seasons

Abstract Three herbicide premixes have recently been introduced for weed control in wheat. These include: halauxifen + florasulam, thifensulfuron + fluroxypyr, and bromoxynil + bicyclopyrone. The objective of this study was to evaluate these herbicides along with older products for their control of smallseed falseflax in winter wheat in Oklahoma. Studies took place during the 2017, 2018, and 2020 winter wheat growing seasons. Weed control was visually estimated every two weeks throughout the growing season and wheat yield was collected in all three years. Smallseed falseflax size was approximately six cm in diameter at time of application in all years. Control ranged from 96 to 99% following all treatments with the exception of bicyclopyrone + bromoxynil and dicamba alone, which controlled falseflax 90%. All treatments containing an acetolactate synthase (ALS)-inhibiting herbicide achieved adequate control; therefore, resistance is not suspected in this population. Halauxifen + florasulam and thifensulfuron + fluroxypyr effectively controlled smallseed falseflax similarly to other standards recommended for broadleaf weed control in wheat in Oklahoma. Rotational use of these products allows producers flexibility in controlling smallseed falseflax and reduces the potential for development of herbicide resistance in this species.

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Weed Control in Pepper

EDIS ◽

10.32473/edis-wg034-2006 ◽

2006 ◽

Vol 2006 (17) ◽

Author(s):

William M. Stall ◽

James P. Gilreath

Keyword(s):

Weed Control ◽

Weed Management ◽

Control Program ◽

Fact Sheet ◽

Cultural Methods

Revised! HS-199, a 5-page fact sheet by William M. Stall and James P. Gilreath, describes a weed control program that integrates chemical, mechanical, and cultural methods and provides a table of listing herbicides available to growers for chemical weed control of pepper. This publication updates the 2003 tables to reflect current recommendations. Published by the UF Department of Horticultural Sciences, October 2006. HS199/WG034: Weed Management in Pepper (ufl.edu)

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Influence of Weed Control Programs in Intensive Cropping Systems

Weed Science ◽

10.1017/s0043174500059956 ◽

1984 ◽

Vol 32 (6) ◽

pp. 762-767 ◽

Cited By ~ 6

Author(s):

N. C. Glaze ◽

C. C. Dowler ◽

A. W. Johnson ◽

D. R. Sumner

Keyword(s):

Weed Control ◽

Cropping Systems ◽

Weed Species ◽

Multiple Cropping ◽

Control Programs ◽

Yellow Nutsedge ◽

Herbicide Treatments ◽

Intensive Cropping ◽

Main Effects ◽

Herbicide Programs

Six multiple-cropping systems composed of: a) turnip (Brassica campestrisspp.rapifera), corn (Zea maysL.), and snapbean (Phaseolus vulgarisL.); b) turnip, peanut (Arachis hypogaeaL.), and snapbean; c) turnip, corn, and turnip; d) turnip, peanut, and turnip; e) snapbean, soybean [Glycine max(L.) Merr.], and cabbage (Brassica oleraceaL.); and f) turnip, cucumber (Cucumis sativusL.), cowpea [Vigna unguiculata(L.) Walp.], and turnip were subjected to nematicide and weed control programs of cultivation or herbicides. Herbicide programs were superior to cultivation in control of weeds. Weeds remaining in the row following cultivation competed severely with crops. Weed species remaining were altered depending on the method of control and crop. Yellow nutsedge (Cyperus esculentusL. ♯3CYPES) increased rapidly in all herbicide programs but not in cultivated plots. Pigweeds (Amaranthusspp.) were controlled by herbicides but increased in cultivated plots. Corn, peanut, soybean, and spring snapbean yields were higher in herbicide treatments than in cultivated treatments. Cucumber was the only crop that had increased yields for both main effects, herbicide and nematicide. Turnip was consistently injured in herbicide treatments, which was believed to be caused by residues from previous crops interacting with pathogens and possible allelopathic effects of decaying organic matter.

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Tolerance of Cotton (Gossypium hirsutum) Seedlings to Preemergence and Postemergence Herbicides with Four Modes of Action

Plant Health Progress ◽

10.1094/php-2007-1108-01-rs ◽

2007 ◽

Vol 8 (1) ◽

pp. 4 ◽

Cited By ~ 5

Author(s):

J. A. Kendig ◽

R. L. Nichols ◽

G. A. Ohmes

Keyword(s):

Gossypium Hirsutum ◽

Weed Control ◽

Control Program ◽

Control Programs ◽

Modes Of Action ◽

Greenhouse Study ◽

Crop Injury ◽

Postemergence Herbicides ◽

Residual Herbicide ◽

Over The Top

The current dominant weed control program in cotton relies heavily on glyphosate. Typical glyphosate-based weed control programs require repeat applications. A residual herbicide might reduce the number of herbicide applications needed, and potentially reduce costs. Residual herbicides that can be used postemergence in cotton are limited in number, and there are few studies evaluating the response of cotton to over-the-top application of herbicides. A greenhouse study evaluated response of cotton to fluometuron, propazine, metolachlor, pyrithiobac, and glyphosate. Most of these herbicides caused minimal crop injury; however, fluometuron and propazine caused significant visual injury when applied over-the-top at the cotyledon and two-leaf stages, but less injury when applied preemergence. Accepted for publication 5 July 2007. Published 8 November 2007.

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Season-long weed control with sequential herbicide programs in California tree nut crops

Weed Technology ◽

10.1017/wet.2020.70 ◽

2020 ◽

Vol 34 (6) ◽

pp. 834-842

Author(s):

Caio A. C. G. Brunharo ◽

Seth Watkins ◽

Bradley D. Hanson

Keyword(s):

Weed Control ◽

Field Experiments ◽

Control Program ◽

Early Spring ◽

High Rate ◽

Weed Species ◽

Tree Nut ◽

Herbicide Use ◽

Herbicide Programs ◽

Grass Weed

AbstractWeed control in tree nut orchards is a year-round challenge for growers that is particularly intense during winter through summer as a result of competition and interference with management and harvest operations. A common weed control program consists of an application of a winter PRE and POST herbicide mixture, followed by a desiccation treatment in early spring and before harvest. Because most spring and summer treatments depend on a limited number of foliar-applied herbicides, summer-germinating species and/or herbicide-resistant biotypes become troublesome. Previous research has established effective PRE herbicide programs targeting winter glyphosate-resistant weeds. However, more recently, growers have reported difficulties in controlling several summer-germinating grass weeds with documented or suspected resistance to the spring and summer POST herbicide programs. In this context, research was conducted to evaluate a sequential PRE approach to control winter- and summer-germinating orchard weeds. Eight field experiments were conducted in tree nut orchards to evaluate the efficacy of common winter herbicide programs and a sequential herbicide program for control of a key summer grass weed species. In the sequential-application strategy, three foundational herbicide programs applied in the winter were either mixed with pendimethalin, followed with pendimethalin in March, or applied as a split application of pendimethalin in both winter and spring. Results indicate that the addition of pendimethalin enhanced summer grass weed control throughout the crop growing season by up to 31%. Applying all or part of the pendimethalin in the spring improved control of the summer grass weed junglerice by up to 49%. The lower rate of pendimethalin applied in the spring performed as well as the high rate in the winter, suggesting opportunities for reducing herbicide inputs. Tailoring sequential herbicide programs to address specific weed challenges can be a viable strategy for improving orchard weed control without increasing herbicide use in some situations.

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Physical weed control in processing tomatoes in Central Italy

Renewable Agriculture and Food Systems ◽

10.1017/s1742170510000578 ◽

2011 ◽

Vol 26 (2) ◽

pp. 95-103 ◽

Cited By ~ 6

Author(s):

Michele Raffaelli ◽

Marco Fontanelli ◽

Christian Frasconi ◽

Francesca Sorelli ◽

Marco Ginanni ◽

...

Keyword(s):

Weed Control ◽

Weed Management ◽

Central Italy ◽

Physical Treatment ◽

Growing Seasons ◽

Organic Cultivation ◽

Alternative System ◽

Hand Weeding ◽

Physical Weed Control ◽

Processing Tomatoes

AbstractTomato is a very important vegetable crop in Italy. Improving the means of production for processing organic tomatoes could help guarantee better profits for farmers and, at the same time, enhance environmental management and safeguard consumers’ health. Weed control, in particular within crop rows, is one of the main problems in organic farming, and thus also for the organic cultivation of tomato. The aim of this study was to develop innovative strategies and equipment for effective physical weed control in processing tomatoes. A conventional weed management system incorporating herbicides was compared with an alternative system relying exclusively on physical control during three growing seasons (2006–2008) on a farm located near Pisa, Italy. The crop was transplanted mechanically onto paired rows. The conventional strategy consisted of three different chemical treatments, two post-transplanting PTO-powered rotary hoe passes and several hand-weeding treatments on the paired rows. The alternative system included a stale seedbed technique (performed by a rolling harrow pass and one flaming treatment), two post-transplanting precision hoeing treatments and several hand-weeding treatments. All the machines for the alternative system were adjusted and set up for processing tomatoes transplanted in paired rows. Each physical treatment (mechanical and thermal) within the alternative system allowed an ‘instantaneous’ (just before/just after) weed control from 50 to 100%, while the alternative strategy as a whole achieved values of weed dry biomass at harvest ranging from 22 to 126 g m−2. However, the alternative system required a total labor input that averaged 50% higher than the conventional strategy. The conventional system had on average more effective weed control than the alternative system, but both strategies controlled weeds effectively. Weed biomass at harvest averaged 36 and 68 g m−2 for conventional and alternative strategies, respectively. On the other hand, the alternative system generally led to a significant increase in fresh crop yield (+13% average yield for the 3 years).

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