Row Width Affects Weed Management in Type II Black Bean

Field studies were conducted in 2010 and 2011 at two locations in Michigan to examine the effect of row width and herbicide combination on weed suppression and yield in the new Type II black bean variety ‘Zorro.' Black bean was planted in 38- and 76-cm rows. Six weed control strategies were examined:S-metolachlor + halosulfuron (PRE),S-metolachlor (PRE) followed by (fb) bentazon + fomesafen (POST), halosulfuron (PRE) fb clethodim (+ fomesafen at one site in one year) (POST), imazamox + bentazon (POST), a weed-free control, and a nontreated control. Weed control and crop injury were evaluated throughout the growing season. In addition, weeds were counted by species in late July, and weed biomass was harvested and weighed at the end of the season. Black bean yield was obtained by direct harvest. Narrow rows reduced weed populations in two of the four site–year combinations (referred to hereafter as site–years), reduced weed biomass in three of the four site–years, and often improved control of upright broadleaf weeds. All herbicide combinations generally reduced weed populations and biomass, but control of specific weeds was variable. Crop injury was generally slight and transient. Yield was greater in narrow rows in two of the four site–years. All herbicide combinations increased yield compared with the nontreated control and resulted in similar yields to one another. Yield and weed suppression was often maximized in narrow rows, while herbicide performance varied by year and weed spectrum.

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Spring-planted cover crops for weed control in soybean

Renewable Agriculture and Food Systems ◽

10.1017/s1742170521000107 ◽

2021 ◽

pp. 1-8

Author(s):

Katja Koehler-Cole ◽

Christopher A. Proctor ◽

Roger W. Elmore ◽

David A. Wedin

Keyword(s):

Weed Control ◽

Biomass Production ◽

Cover Crops ◽

Weed Management ◽

Block Design ◽

Weed Suppression ◽

Crop Species ◽

Cold Temperatures ◽

Weed Biomass ◽

Small Grains

Abstract Replacing tillage with cover crops (CC) for weed management in corn (Zea mays L.)-soybean [Glycine max (L.) Merr.] systems with mechanical weed control has many soil health benefits but in the western Corn Belt, CC establishment after harvest is hampered by cold temperatures, limited labor and few compatible CC species. Spring-planted CC may be an alternative, but information is lacking on suitable CC species. Our objective was to evaluate four spring-planted CC with respect to biomass production and weed suppression, concurrent with CC growth and post-termination. Cover crop species tested were oat (Avena sativa L.), barley (Hordeum vulgare L.), brown mustard [Brassica juncea (L.) Czern.] and yellow mustard (Brassica hirta Moench). They were compared to no-CC treatments that were either tilled pre- and post-planting of soybean (no-CC tilled) or not tilled at all (no-CC weedy). CC were planted in late March to early April, terminated 52–59 days later using an undercutter, and soybean was planted within a week. The experiment had a randomized complete block design with four replications and was repeated for 3 years. Mustards and small grains produced similar amounts of biomass (1.54 Mg ha−1) but mustard biomass production was more consistent (0.85–2.72 Mg ha−1) than that of the small grains (0.35–3.81 Mg ha−1). Relative to the no-CC weedy treatment, mustards suppressed concurrent weed biomass in two out of 3 years, by 31–97%, and small grains suppressed concurrent weed biomass in only 1 year, by 98%. Six weeks after soybean planting, small grains suppressed weed biomass in one out of 3 years, by 79% relative to the no-CC weedy treatment, but mustards did not provide significant weed suppression. The no-CC tilled treatment suppressed weeds each year relative to the no-CC weedy treatment, on average 87%. The ineffective weed control by CC reduced soybean biomass by about 50% six weeks after planting. While spring-planted CC have the potential for pre-plant weed control, they do not provide adequate early season weed suppression for soybean.

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Effects of Management Type and Timing on Weed Suppression in Soybean No-Till Planted into Rolled-Crimped Cereal Rye

Weed Science ◽

10.1614/ws-d-12-00024.1 ◽

2012 ◽

Vol 60 (4) ◽

pp. 624-633 ◽

Cited By ~ 25

Author(s):

Eric A. Nord ◽

Matthew R. Ryan ◽

William S. Curran ◽

David A. Mortensen ◽

Steven B. Mirsky

Keyword(s):

Weed Control ◽

Community Composition ◽

Weed Management ◽

Cover Crop ◽

Weed Suppression ◽

Planting Dates ◽

Weed Biomass ◽

Cereal Rye ◽

No Till ◽

Weed Emergence

Knowledge of weed emergence periodicity can inform the timing and choice of weed management tactics. We tested the effects of weed management system (conventional [CNV] and herbicide-free [HF]), timing of rye sowing (two dates), timing of soybean planting (5 planting dates, 3 in each system), and supplemental control (with and without) on weed suppression and weed community composition in soybean no-till planted into a cereal rye cover crop. Cereal rye was terminated with a roller-crimper and herbicide (CNV) or with a roller-crimper alone (HF), and supplemental weed control was achieved with a postemergence glyphosate application (CNV) or with interrow high-residue cultivation (HF). Supplemental control with glyphosate in CNV was more effective than high-residue cultivation in HF. When soybean was planted on the same date, CNV resulted in less weed biomass and a more even community composition, whereas HF resulted in greater weed biomass, dominated by common ragweed. When we controlled for cereal rye biomass and compared the effects of cereal rye sowing and termination timing within each system, earlier management reduced weed biomass in HF, but tended to increase weed biomass in CNV. Our results suggest the ability to control emerged weeds prior to soybean planting is an important factor that influences the optimal cereal rye cover crop management timing for weed suppression.

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Integrated Weed Management Using Planting Pattern, Cultivar, and Herbicide in Dry-Seeded Rice in Northwest India

Weed Science ◽

10.1614/ws-d-13-00115.1 ◽

2014 ◽

Vol 62 (2) ◽

pp. 350-359 ◽

Cited By ~ 11

Author(s):

Gulshan Mahajan ◽

Vikas Poonia ◽

Bhagirath S. Chauhan

Keyword(s):

Grain Yield ◽

Weed Control ◽

Weed Management ◽

Field Experiments ◽

Weed Suppression ◽

Integrated Weed Management ◽

Rice Grain ◽

Planting Pattern ◽

Weed Biomass ◽

Northwest India

Field experiments were conducted in Punjab, India, in 2011 and 2012 to study the integrated effect of planting pattern [uniform rows (20-cm spacing) and paired rows (15-, 25-, and 15-cm spacing)], cultivars (PR-115 and IET-21214), and weed control treatments (nontreated control, pendimethalin 750 g ai ha−1, bispyribac-sodium 25 g ai ha−1, and pendimethalin 750 g ha−1 followed by bispyribac-sodium 25 g ha−1) on weed suppression and rice grain yield in dry-seeded rice. In the nontreated control, IET-21214 had higher grain yield than PR-115 in both planting patterns. However, such differences were not observed within the herbicide treatment. IET-21214 in paired rows, even in nontreated control, provided grain yield (4.7 t ha−1) similar to that in uniform rows coupled with the sole application of pendimethalin (4.3 t ha−1) and bispyribac-sodium (5.0 t ha−1). In uniform rows, sequential application of pendimethalin (PRE) and bispyribac-sodium (POST) provided the highest grain yield among all the weed control treatments and this treatment produced grain yield of 5.9 and 6.1 t ha−1 for PR-115 and IET-21214, respectively. Similarly, in paired rows, PR-115 in paired rows treated with sequential application of pendimethalin and bispyribac-sodium had highest grain yield (6.1 t ha−1) among all the weed control treatments. However, IET-21214 with the sole application of bispyribac-sodium produced grain yield similar to the sequential application of pendimethalin and bispyribac-sodium. At 30 days after sowing, PR-115 in paired rows coupled with pendimethalin application accrued weed biomass (10.7 g m−2) similar to the sequential application of pendimethalin and bispyribac-sodium coupled with uniform rows (8.1 g m−2). Similarly, IET-21214 with bispyribac-sodium application provided weed control similar to the sequential application of pendimethalin and bispyribac-sodium. Our study implied that grain yield of some cultivars could be improved by exploring their competitiveness through paired-row planting patterns with less use of herbicides.

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Weed Management in Wide- and Narrow-Row Glyphosate-Resistant Sugarbeet

Weed Technology ◽

10.1614/wt-d-10-00033.1 ◽

2010 ◽

Vol 24 (4) ◽

pp. 523-528 ◽

Cited By ~ 10

Author(s):

Jon-Joseph Q. Armstrong ◽

Christy L. Sprague

Keyword(s):

Weed Control ◽

Weed Management ◽

Field Studies ◽

Weed Competition ◽

Yield And Quality ◽

Row Width ◽

Herbicide Treatments ◽

Narrow Row

Planting glyphosate-resistant sugarbeet in narrow rows could improve weed control with fewer herbicide applications and cultivations. Field studies were conducted in 2007 and 2008 at multiple locations in Michigan to compare weed management and sugarbeet yield and quality in glyphosate-resistant sugarbeet planted in 38-, 51-, and 76-cm rows. At all locations, weed densities and biomass were less after glyphosate treatments than after conventional herbicide treatments. Weed densities and biomass also were less in 38- and 51-cm rows compared with 76-cm rows following a single glyphosate application when weeds were 10 cm tall. Averaged over row width, sugarbeet treated with glyphosate when weeds first reached 2 cm in height and again as needed thereafter yielded similarly to sugarbeet treated when weeds were 5 to 10 cm tall. However, root yields were reduced when glyphosate application was delayed until weeds averaged 15 cm in height. Sugarbeet root and sugar yields were greater from 38- and 51-cm row widths than from the 76-cm row widths, averaged over all herbicide treatments. Regardless of row width, initial glyphosate applications should be made before weeds reach 10 cm in height to maximize yield and minimize weed competition with sugarbeet.

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Effect of Separate and Combined Applications of Herbicides on Weed Control and Yield of Sugar Beet

Weed Technology ◽

10.1614/wt-03-142r2 ◽

2004 ◽

Vol 18 (4) ◽

pp. 968-976 ◽

Cited By ~ 9

Author(s):

Farzin Abdollahi ◽

Hossein Ghadiri

Keyword(s):

Sugar Beet ◽

Weed Control ◽

Field Studies ◽

Sucrose Content ◽

Weed Biomass ◽

Maximum Reduction ◽

Agronomic Characteristics ◽

Crop Injury ◽

Herbicide Treatments

Field studies were conducted to investigate the effects of different rates of herbicides on weed control, agronomic characteristics, and quality of sugar beet at Shiraz, Iran, in 2000 and 2001. Separate and combined applications of herbicides, including 14 combinations and different rates of grass and broadleaf herbicides, at two rates were used. Herbicides reduced weed biomass compared with the weedy check. In both years, maximum reduction in weed biomass was observed with desmedipham plus phenmedipham plus ethofumesate at 0.23 + 0.23 + 0.23 kg ai/ha and desmedipham plus phenmedipham plus propaquizafop at 0.46 + 0.46 + 0.1 kg ai/ha. Efficacy of grass herbicides was reduced when they were combined with pyrazon. Highest crop injury in both years was observed with desmedipham plus phenmedipham plus ethofumesate at 0.23 + 0.23 + 0.23 kg/ ha. Highest and lowest root yields in both years were produced in weed-free and weedy check plots, respectively. All herbicide treatments produced lower sugar beet yields than the hand-weeded check. Of the herbicide treatments evaluated, the highest sugar beet yields were with desmedipham plus phenmedipham plus propaquizafop at 0.46 + 0.46 + 0.1 kg/ha in 2001 and with desmedipham plus phenmedipham plus ethofumesate at 0.23 + 0.23 + 0.23 kg/ha in 2000. Sucrose content and other sugar beet brei characteristics were not affected by the herbicide treatments.

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High-Residue Cultivation Timing Impact on Organic No-Till Soybean Weed Management

Weed Technology ◽

10.1017/wet.2016.24 ◽

2017 ◽

Vol 31 (2) ◽

pp. 320-329 ◽

Cited By ~ 5

Author(s):

Gladis M. Zinati ◽

Rita Seidel ◽

Alison Grantham ◽

Jeff Moyer ◽

Victoria J. Ackroyd ◽

...

Keyword(s):

Weed Control ◽

Weed Management ◽

Cover Crop ◽

Weed Suppression ◽

Management Approach ◽

Optimal Timing ◽

Weed Biomass ◽

Cereal Rye ◽

Organic Cultivation ◽

No Till

A cereal rye cover crop mulch can suppress summer annual weeds early in the soybean growing season. However, a multi-tactic weed management approach is required when annual weed seedbanks are large or perennial weeds are present. In such situations, the weed suppression from a cereal rye mulch can be supplemented with the use of high-residue cultivators which can prolong the weed-free period during soybean growth. Research trials were conducted to determine the optimum timing of high-residue cultivation for weed control in rolled-crimped cereal rye mulches. Treatments included three cultivation timings with a high-residue cultivator: early (3-4 wk after soybean planting (WAP)), intermediate (5-6 WAP), and late (7-8 WAP), a weed-free and no-cultivation control. Crop and weed measurement included cereal rye biomass, weed biomass, soybean population and biomass, and yield. Cereal rye biomass was 50% lower and weed biomass was three times greater in 2011 than in 2010 and 2012 due to 2011 being a dry year. There was no significant effect of cultivation timing on soybean population when compared to no-cultivation or hand-weeded treatments. While cultivation reduced weed biomass by 67% compared to no-cultivation, soybean yield was only improved by 12% in early and late cultivation treatments and 22% in intermediate cultivation treatment when compared to no-cultivation. Effective strategies for improving weed management by integrating the use of a high-residue cultivator in no-till organic systems could help existing organic field crop producers to reduce tillage while also encourage adoption of organic crop production by conventional growers who prefer reduced-tillage systems. Unlike traditional organic cultivation equipment, therefore, optimal timing of cultivation should be delayed several weeks in organic cover crop-based no-till planted soybean production as compared to the typical tillage-based approach to ensure both weed control and optimal yield.

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Developing a multispecies weed competition model for high-yielding cotton

Weed Technology ◽

10.1017/wet.2020.97 ◽

2020 ◽

pp. 1-8

Author(s):

Graham W. Charles ◽

Brian M. Sindel ◽

Annette L. Cowie ◽

Oliver G. G. Knox

Keyword(s):

Weed Control ◽

Weed Management ◽

Production Systems ◽

Integrated Approach ◽

Field Studies ◽

Integrated Weed Management ◽

Cotton Lint ◽

Weed Biomass ◽

Models Comparison ◽

Using Data

Abstract Glyphosate-tolerant and glyphosate-resistant weeds are becoming increasingly problematic in cotton fields in Australia, necessitating a return from a glyphosate dominated system to a more integrated approach to weed management. The development of an integrated weed management system can be facilitated by identifying the critical period for weed control (CPWC), a model that enables cotton growers to optimize the timing of their weed control inputs. Using data from field studies conducted from 2003 to 2015, CPWC models using extended functions, including weed biomass in the relationships, were developed for the mimic weeds, common sunflower and Japanese millet, in high-yielding, fully irrigated cotton. A multispecies CPWC model was developed after combining these data sets with data for mungbean in irrigated cotton, using weed height and weed biomass as descriptors in the models. Comparison of observed and predicted relative cotton-lint yields from the multispecies CPWC model demonstrated that the model reasonably described the competition from these three very different mimic weeds, opening the possibility for cotton growers to use a multispecies CPWC model in their production systems.

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Integrative Approaches for Weed Management in Organic Citrus Orchards

HortScience ◽

10.21273/hortsci.41.4.998a ◽

2006 ◽

Vol 41 (4) ◽

pp. 998A-998

Author(s):

Jose Linares ◽

Johannes Scholberg ◽

Carlene Chase ◽

Robert McSorley ◽

James Fergusson

Keyword(s):

Weed Control ◽

Cover Crops ◽

Weed Management ◽

Pigeon Pea ◽

Weed Suppression ◽

Velvet Bean ◽

Weed Biomass ◽

Crimson Clover ◽

Weed Growth ◽

Sunn Hemp

Lack of effective weed control may hamper organic citrus establishment. Cover crop/weed biomass (CCW) indices were used to assess the effectiveness of annual and perennial cover crops (CC) in reducing weed growth. The CCW values for perennial peanut (PP) were 0.06, 0.14, 0.4, and 0.5 during 2002, 2003, 2004, and 2005, respectively (very poor to poor weed control). Initial PP growth was slow and repeated mowing was required, but, over time, PP became more effective in controlling weeds. Weed biomass with sunn hemp was 0.3 Mg/ha in 2002 (CCW = 25, outstanding weed control) compared to 1.4 Mg/ha with use of cowpea (CCW = 1) in 2004. In 2004, the dry weights (Mg/ha) for different summer CC were: hairy indigo = 7.6, pigeon pea = 7.6, sunn hemp = 5.3, cowpea = 5.1, alyce clover = 2.9, velvet bean = 1.3, and lablab bean = 0.8. Corresponding 2005 values were: 9.5, 3.7, 12.6, 1.0, 1.9, and 1.4. Respective CCWI values were: 7, 4, 2, 16, 28, 0.6, and 0.3 (2004) vs. 17, 2, 64, 80, 0.5, 2, and 14. In 2004, winter CC production (Mg/ha) was radish (R) = 3.2, crimson clover (CR) = 1.7, oats (O) + lupine = 1.6, and rye (WR)/vetch (V) mix = 1.1. Results for 2005 were: CR + R + WR = 8.0, WR = 6.0; CR + WR = 5.3, CR = 5.0, CR + O + WR = 5.0, R = 4.3, and O = 3.6 Mg/ha. Corresponding values for CCW-indices were 15, 2, 1, and 3 (2004) and 100, 25, 76, 35, 62, 11, and 16 (2005). Although OMRI-approved herbicides showed up to 84% weed injury for selected species, none of these products provided long-term weed control. Combination of repeated tillage, use of compact/reseeding CC mixes in tree rows, more vigorous annual CC and/or perennial PP in row middle and repeated use of organic herbicides near sprinklers and tree trunks are thus required to ensure effective weed suppression in organic citrus.

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Postemergence Control of Italian Ryegrass in Hazelnut Orchards

Weed Technology ◽

10.1017/wet.2021.41 ◽

2021 ◽

pp. 1-22

Author(s):

Marcelo L. Moretti

Keyword(s):

Weed Control ◽

Weed Management ◽

Field Studies ◽

Early Spring ◽

Italian Ryegrass ◽

Specific Response ◽

Record Keeping ◽

Effective Option ◽

Contrast Analysis ◽

Herbicide Use

Abstract Italian ryegrass has become a problematic weed in hazelnut orchards of Oregon because of the presence of herbicide-resistant populations. Resistant and multiple-resistant Italian ryegrass populations are now the predominant biotypes in Oregon; there is no information on which herbicides effectively control Italian ryegrass in hazelnut orchards. Six field studies were conducted in commercial orchards to evaluate Italian ryegrass control with POST herbicides. Treatments included flazasulfuron, glufosinate, glyphosate, paraquat, rimsulfuron, and sethoxydim applied alone or in selected mixtures during early spring when plants were in the vegetative stage. Treatment efficacy was dependent on the experimental site. The observed range of weed control 28 d after treatment was 13 to 76 % for glyphosate, 1 to 72% for paraquat, 58 to 88% for glufosinate, 16 to 97 % for flazasulfuron, 8 to 94% for rimsulfuron, and 25 to 91% for sethoxydim. Herbicides in mixtures improved control of Italian ryegrass compared to single active ingredients based on contrast analysis. Herbicides in mixture increased control by 27% compared to glyphosate, 18% to rimsulfuron, 15% to flazasulfuron, 19% to sethoxydim, and 12% compared to glufosinate when averaged across all sites, but mixture not always improved ground coverage of biomass reduction. This complex site-specific response highlights the importance of record-keeping for efficient herbicide use. Glufosinate is an effective option to manage Italian ryegrass. However, the glufosinate-resistant biotypes documented in Oregon may jeopardize this practice. Non-chemical weed control options are needed for sustainable weed management in hazelnuts.

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Weed Control with Reduced Rates of Chlorimuron Plus Metribuzin and Imazethapyr in No-Till Narrow-Row Soybean (Glycine max)

Weed Technology ◽

10.1017/s0890037x00042536 ◽

1998 ◽

Vol 12 (1) ◽

pp. 32-36 ◽

Cited By ~ 9

Author(s):

William G. Johnson ◽

Jeffrey S. Dilbeck ◽

Michael S. Defelice ◽

J. Andrew Kendig

Keyword(s):

Glycine Max ◽

Weed Control ◽

Field Studies ◽

Weed Suppression ◽

Crop Response ◽

Soybean Production ◽

No Till ◽

Giant Foxtail ◽

The Difference ◽

Narrow Row

Field studies were conducted at three locations in 1993 and 1994 to evaluate weed control and crop response to combinations of glyphosate, metolachlor, 0.5 X and 1 X label rates of chlorimuron plus metribuzin applied prior to planting (PP), and 0.5 X and 1 X label rates of imazethapyr applied early postemergence (EPOST) or postemergence (POST) in no-till narrow-row soybean production. Giant foxtail densities were reduced with sequential PP followed by (fb) EPOST or POST treatments. Large crabgrass was reduced equivalently with all herbicide combinations involving chlorimuron plus metribuzin PP fb imazethapyr. Common cocklebur control was variable but was usually greater with treatments that included imazethapyr. Ivyleaf morningglory densities were not reduced with any herbicide combinations. Sequential PP fb EPOST or POST treatments tended to provide slightly better weed suppression than PP-only treatments, but the difference was rarely significant. Soybean yields with treatments utilizing 0.5 X rates were usually equal to 1 X rates.

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