An Integrated Weed Management Approach to Managing Foxtail Barley (Hordeum jubatum) in Conservation Tillage Systems

A 4-yr field experiment was conducted to determine the merits of combining cultural and chemical controls to manage foxtail barley in reduced-tillage systems. Factors studied were crop row spacing, seeding rate, and application rate and timing of glyphosate within a spring wheat-flax cropping sequence. Glyphosate applied preseeding at 400 or 800 g/ha killed foxtail barley seedlings but only suppressed established perennial plants. Glyphosate applied postharvest at 800 g/ha killed 60 to 70% of established plants. Combinations of preseeding and postharvest glyphosate gave the greatest reductions in foxtail barley biomass and seed production and resulted in the greatest increases in crop yield. Including flax in the rotation allowed use of grass herbicides such as quizalofop or sethoxydim that effectively controlled foxtail barley seedlings and provided some suppression of perennial plants. An increase in wheat seeding rate from 75 to 115 kg/ha reduced foxtail barley growth and increased wheat yield in 3 of 4 yr. Increasing the flax seeding rate from 40 to 80 kg/ha or reducing wheat and flax row spacing from 30 to 20 cm provided little benefit in managing foxtail barley or increasing crop yield. A multiyear approach combining agronomic practices and timely use of herbicides should allow growers to effectively manage foxtail barley in annual cropping systems using conservation tillage.

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Seeding rate and row spacing affect flax yields and weed interference

Canadian Journal of Plant Science ◽

10.4141/cjps96-098 ◽

1996 ◽

Vol 76 (3) ◽

pp. 537-544 ◽

Cited By ~ 16

Author(s):

F. C. Stevenson ◽

A. T. Wright

Keyword(s):

Seed Yield ◽

Weed Management ◽

Management Practices ◽

The Other ◽

Integrated Weed Management ◽

Row Spacing ◽

Flax Seed ◽

Seeding Rate ◽

Weed Interference ◽

Interference Study

Seeding rate and row spacing are management practices that affect flax seed yield. Two experiments were conducted from 1988 to 1990 to determine the influence of flax seeding rates (300, 600, and 900 seeds m−2) and row spacings (9, 18, and 27 cm). One was a flax-weed interference study (three sites) and the other was a weed-free study (13 sites). In the presence of weeds, increasing seeding rate from 300 to 900 seeds m−2 improved flax seed yield by 180 kg ha−1, and reduced broadleaf weed yields by 300 kg ha−1 and grassy weed yields by 180 kg ha−1. In weed-free conditions, seed yield was not affected by seeding rate. Row spacing did not affect flax yield and had minor effects on weed yields when weeds were not controlled. When weeds were controlled, seed yield in the 9-cm row spacing was 9% (15% in the flax-weed interference study) greater than in the two wider row spacings. Seeding rate and row spacing independently influenced flax yield, and their effect was consistent among sites with weeds present, but was not consistent when weeds were controlled. Our results showed that flax seeding rate was an important component of integrated weed management. Key words: Flax, seeding rate, row spacing, weed interference

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Sustainability, conservation tillage and weeds in Canada

Canadian Journal of Plant Science ◽

10.4141/cjps96-115 ◽

1996 ◽

Vol 76 (4) ◽

pp. 651-659 ◽

Cited By ~ 22

Author(s):

D. A. Derksen ◽

R. E. Blackshaw ◽

S. M. Boyetchko

Keyword(s):

Biological Control ◽

Weed Management ◽

Conservation Tillage ◽

The United States ◽

Integrated Weed Management ◽

Biological Weed Control ◽

Plant Residues ◽

Tillage Systems ◽

Weed Communities ◽

Inundative Biological Control

The sustainability of conservation tillage is dependent on the extent of changes in weed community composition, the usage of herbicides, and the development of integrated weed management (IWM) strategies, including biological weed control. The objective of this paper is to review research on conservation tillage and weed management in light of these factors. Recent Canadian research has found that changes in weed communities due to the adoption of conservation tillage are not necessarily those expected and were not consistant by species, location, or year. Changes reflected the use of different selection pressures, such as different crop rotations and herbicides, within the studies to a greater extent than weed life cycle groupings. Therefore, research that determines the reasons for change or the lack of change in weed communities is required to provide the scientific basis for the development of IWM strategies. Documented herbicide usage in conservation tillage varies from less than to more than conventional-tillage systems. Potential to reduce herbicide usage in conservation-tillage systems exists. Furthermore, the herbicides used in western Canada are different from those causing ground water contamination in the United States, are less volatile, and are used at lower rates. The presence of surface crop residues in conservation tillage may provide a unique environment for classical and inundative biological control agents. Some insects, fungi, and bacteria have the potential to survive to a greater extent in undisturbed plant residues. Residue management and conservation tillage systems are evolving in Canada. Research must keep pace by providing weed management strategies that enchance the sustainability of these systems. Key words: Biological control, zero tillage, integrated weed management, residues, herbicides, rhizobacteria.

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Tillage, fertiliser and glyphosate timing effects on foxtail barley (Hordeum jubatum) management in wheat

Canadian Journal of Plant Science ◽

10.4141/p99-132 ◽

2000 ◽

Vol 80 (3) ◽

pp. 655-660 ◽

Cited By ~ 14

Author(s):

R. E. Blackshaw ◽

G. Semach ◽

X. Li ◽

J. T. O'Donovan ◽

K. N. Harker

Keyword(s):

Weed Management ◽

Production Systems ◽

Conservation Tillage ◽

Wheat Yield ◽

Soil Surface ◽

Integrated Weed Management ◽

Canadian Prairies ◽

Application Timing ◽

Hordeum Jubatum ◽

Timing Effects

Foxtail barley (Hordeum jubatum L.) is becoming a more severe weed problem as conservation tillage becomes widely adopted on the southern Canadian prairies. A 5-yr field study was conducted to determine the combined effects of tillage, N rate, N placement and application timing of glyphosate to manage foxtail barley in spring wheat. Wide-blade tillage conducted in fall and spring, compared to zero-till, reduced foxtail barley biomass and seed production in all yr and increased wheat yield in 4 of 5 yr. Foxtail barley was highly competitive with wheat for added N. N fertiliser placed mid-row in 10-cm-deep bands reduced foxtail barley growth in 2 of 5 yr and increased wheat yield in 3 of 5 yr compared with soil surface broadcast N. Wheat yield sometimes was similar when N was banded at 60 kg ha−1 or broadcast at 120 kg ha−1, indicating the large advantage of banding N in some situations. Glyphosate at 800 g ha−1 applied preharvest or postharvest gave similar levels of foxtail barley control in 2 of 3 yr. Results indicate that foxtail barley can be adequately managed in wheat production systems utilizing conservation tillage. Key words: Foxtail barley, Hordeum jubatum, glyphosate, integrated weed management, nitrogen placement, zero tillage

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Weed Management and Cotton Yield under Two Row Spacings in Conventional and Conservation Tillage Systems Utilizing Conventional, Glufosinate-, and Glyphosate-based Weed Management Systems

Weed Technology ◽

10.1614/wt-d-10-00124.1 ◽

2011 ◽

Vol 25 (4) ◽

pp. 542-547 ◽

Cited By ~ 9

Author(s):

J. S. Aulakh ◽

A. J. Price ◽

K. S. Balkcom

Keyword(s):

Weed Management ◽

Management System ◽

Conservation Tillage ◽

Conventional Tillage ◽

Palmer Amaranth ◽

Management Systems ◽

Row Spacing ◽

Cotton Yield ◽

Tillage Systems ◽

Large Crabgrass

A field experiment was conducted during three cropping seasons to compare weed control and cotton yield provided by conventional (CV), glufosinate-resistant (LL), and glyphosate-resistant (RR) weed management systems under standard (102 cm) and narrow (38 cm) row spacing grown in conventional and conservation tillage systems. The conventional tillage and/or CV cotton received a PRE application of pendimethalin. The CV, LL, and RR cotton varieties received two POST applications of pyrithiobac, glufosinate, and glyphosate, respectively, at two- and four-leaf cotton growth stages. A final (LAYBY) application of trifloxysulfuron was applied to 38-cm row cotton while a LAYBY POST-directed spray of prometryn plus MSMA was used in 102-cm row cotton. The LL and RR weed management systems controlled at least 97% of large crabgrass, Palmer amaranth, sicklepod, and smallflower morningglory, while the CV system controlled 89, 73, and 87 to 98% of large crabgrass, smallflower morningglory, and Palmer amaranth, respectively. Sicklepod control increased from 85% in 102-cm rows to 95% in 38-cm rows in the CV herbicide system. Yellow nutsedge and pitted morningglory control exceeded 98% and was not affected by tillage, row spacing, or weed management system. Cotton yield was not affected by row spacing any year, by tillage in 2005, or by weed management system in 2004 and 2005. In 2006, yield in the RR weed management system was 27 and 24% higher than LL and CV weed management systems, respectively. In 2004, yield of conventional tillage cotton was 18% higher than conservation tillage cotton, but in 2006 the yield in conservation tillage was 12% higher than conventional tillage.

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Combining agronomic practices and herbicides improves weed management in wheat–canola rotations within zero-tillage production systems

Weed Science ◽

10.1614/ws-04-211r ◽

2005 ◽

Vol 53 (4) ◽

pp. 528-535 ◽

Cited By ~ 25

Author(s):

Robert E. Blackshaw ◽

Hugh J. Beckie ◽

Louis J. Molnar ◽

Toby Entz ◽

James R. Moyer

Keyword(s):

Crop Yield ◽

Spring Wheat ◽

Weed Management ◽

Crop Yields ◽

Wheat Yield ◽

Integrated Weed Management ◽

Weed Biomass ◽

Weed Growth ◽

Spring Canola ◽

Crop Seed

Development of more comprehensive and cost-effective integrated weed management systems is required to facilitate greater integrated weed management adoption by farmers. A field experiment was conducted at two locations to determine the combined effects of seed date (April or May), seed rate (recommended or 150% of recommended), fertilizer timing (applied in fall or spring), and in-crop herbicide dose (50% or 100% of recommended) on weed growth and crop yield. This factorial set of treatments was applied in four consecutive years within a spring wheat–spring canola–spring wheat–spring canola rotation in a zero-till production system. Both wheat and canola phases of the rotation were grown each year. Weed biomass was often lower with May than with April seeding because more weeds were controlled with preplant glyphosate. However, despite fewer weeds being present with May seeding, wheat yield was only greater in 1 of 7 site-years, and canola yield was never greater with May compared with April seeding. Higher crop seed rates had a consistently positive effect on reducing weed growth and the weed seedbank. Crop yield was sometimes greater, and never lower, with higher seed rates. Fertilizer timing did not have a large effect on crop yield, but applying N in the spring compared with fall was less favorable for weeds as indicated by lower weed biomass and a 20% decrease in the weed seedbank. In-crop herbicides applied at 50% compared with 100% doses often resulted in similar weed biomass and crop yield, especially when higher crop seed rates were used. Indeed, the weed seedbank at the conclusion of the 4-yr experiment was not greater with the 50% compared with 100% herbicide dose at one of two locations. This study demonstrates the combined merits of early seeding (April), higher crop seed rates, and spring-applied fertilizer in conjunction with timely but limited herbicide use to manage weeds and maintain high crop yields in rotations containing wheat and canola.

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Agronomic and economic responses to integrated weed management systems and fungicide in a wheat-canola-barley-pea rotation

Canadian Journal of Plant Science ◽

10.4141/p05-165 ◽

2006 ◽

Vol 86 (4) ◽

pp. 1281-1295 ◽

Cited By ~ 19

Author(s):

F. A. Holm ◽

R. P. Zentner ◽

A. G. Thomas ◽

K. Sapsford ◽

A. Légère ◽

...

Keyword(s):

Weed Management ◽

Management Systems ◽

Integrated Weed Management ◽

Zero Tillage ◽

Economic Returns ◽

Seeding Rate ◽

Tillage Systems ◽

Net Return ◽

Tillage System ◽

Herbicide Use

Changes in tillage intensity and herbicide use can influence the incidence of weeds, insects and diseases, crop yields and economic returns. We examined the effects of six integrated weed management systems (with varying combinations of tillage methods, seeding rate, seeding date, time when weed control was applied, and annual fungicide applications on pest incidence, grain yield and quality, and economic returns for a spring wheat (Triticum aestivum L.)-canola (Brassica napus L.)-barley (Hordeum vulgare L.)-pea (Pisum sativum L.) rotation in the Dark Brown soils of the Moist Mixed Grassland Ecoregion of Saskatchewan. Herbicide use intensity was reduced without a significant increase in weed biomass in five of the six systems in most crops and years. The complete elimination of herbicides in one system resulted in significant crop yield losses. Certain insects were more prevalent in the cropping systems with early planting dates. Zero tillage systems produced higher yields, and yields generally declined as tillage intensity increased. For all crops, the high herbicide-zero tillage system produced the highest yields, whereas the lowest yields were obtained in the no herbicide-high tillage system. Management method had minimal impact on seed quality. Application of fungicide generally increased yields of barley, wheat and pea, but the increases were not sufficient to recover fungicide cost. High herbicide-zero tillage, medium herbicide-zero tillage, and low herbicide-zero tillage systems produced the highest net return and no herbicide-high tillage system the lowest net return, under all grain price scenarios. Key words: Agronomic, economic, tillage, herbicide, fungicide, weed management systems, weed, insect, disease

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Spring Wheat, Canola, and Sunflower Response to Persian Darnel (Lolium persicum) Interference

Weed Technology ◽

10.1614/wt-03-056r ◽

2004 ◽

Vol 18 (3) ◽

pp. 509-520 ◽

Cited By ~ 12

Author(s):

Johnathon D. Holman ◽

Alvin J. Bussan ◽

Bruce D. Maxwell ◽

Perry R. Miller ◽

James A. Mickelson

Keyword(s):

Crop Yield ◽

Spring Wheat ◽

Weed Management ◽

Management Practices ◽

Yield Loss ◽

Wheat Yield ◽

Integrated Weed Management ◽

Crop Density ◽

The Impact ◽

Number Of Branches

Integrated weed management practices, such as crop rotation and increased seeding rates, potentially improve weed management. Yet, few studies compare competitive interactions of weeds with different crops. This research quantified the impact of Persian darnel on spring wheat, canola, and sunflower yield across different seeding rates. Increasing crop density increased yield when Persian darnel affected crop yield early in physiological development. Crop yield loss was estimated to reach 83, 70, and 57% for spring wheat, canola, and sunflower, respectively, at high Persian darnel densities. Persian darnel reduced spring wheat yield by limiting the number of tillers per plant and seed per tiller; reduced canola yield by limiting the number of branches per plant, pods per branch, and seed per pod; and reduced sunflower yield by limiting the number of seed per plant. Persian darnel affected crop growth early in physiological development, indicating that interspecific interference occurred early in the growing season. Cultural and resource management aimed at reducing Persian darnel impact on resource availability and crop yield components will reduce Persian darnel impact on crop yield.

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Effect of Row Spacing and Seeding Rate on Russian Thistle (Salsola tragus) in Spring Barley and Spring Wheat

Plants ◽

10.3390/plants10010126 ◽

2021 ◽

Vol 10 (1) ◽

pp. 126

Author(s):

Judit Barroso ◽

Nicholas G. Genna

Keyword(s):

Seed Production ◽

Crop Yield ◽

Spring Wheat ◽

Plant Biomass ◽

Integrated Management ◽

Spring Barley ◽

Management Strategies ◽

Crop Productivity ◽

Row Spacing ◽

Seeding Rate

Russian thistle (Salsola tragus L.) is a persistent post-harvest issue in the Pacific Northwest (PNW). Farmers need more integrated management strategies to control it. Russian thistle emergence, mortality, plant biomass, seed production, and crop yield were evaluated in spring wheat and spring barley planted in 18- or 36-cm row spacing and seeded at 73 or 140 kg ha−1 in Pendleton and Moro, Oregon, during 2018 and 2019. Russian thistle emergence was lower and mortality was higher in spring barley than in spring wheat. However, little to no effect of row spacing or seeding rate was observed on Russian thistle emergence or mortality. Russian thistle seed production and plant biomass followed crop productivity; higher crop yield produced higher Russian thistle biomass and seed production and lower crop yield produced lower weed biomass and seed production. Crop yield with Russian thistle pressure was improved in 2018 with 18-cm rows or by seeding at 140 kg ha−1 while no effect was observed in 2019. Increasing seeding rates or planting spring crops in narrow rows may be effective at increasing yield in low rainfall years of the PNW, such as in 2018. No effect may be observed in years with higher rainfall than normal, such as in 2019.

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Weed Management in Minimum-Tillage Peanuts (Arachis hypogaea) as Influenced by Cultivar, Row Spacing, and Herbicides

Weed Science ◽

10.1017/s0043174500082163 ◽

1985 ◽

Vol 33 (2) ◽

pp. 233-237 ◽

Cited By ~ 22

Author(s):

Daniel L. Colvin ◽

Glenn R. Wehtje ◽

Mike Patterson ◽

Robert H. Walker

Keyword(s):

Arachis Hypogaea ◽

Weed Management ◽

Field Experiments ◽

Sandy Loam ◽

Management Systems ◽

Row Spacing ◽

Seeding Rate ◽

Minimum Tillage ◽

Naphthylphthalamic Acid ◽

Peanut Production

Field experiments were conducted in 1982 and 1983 on a Dothan sandy loam (Plinthic Paleudult) at Headland, AL, to investigate minimum-tillage production of peanuts (Arachis hypogaeaL.). The experiments included two peanut varieties: a) ‘Pronto’ (an earlier maturing Spanish type), and b) ‘Florunner’ (a later maturing runner type). Two row-spacing patterns were used: a) conventional 91-cm rows, and b) a modified twin 18-cm row pattern. A constant seeding rate (140 kg/ha) was used regardless of row spacing. Six herbicide systems were evaluated within each combination of variety and row spacing. The Florunner variety outyielded the Pronto variety across both years and weed management systems. Modified twin 18-cm rows outyielded conventional 91-cm rows across years and peanut varieties. Two of the six weed management systems were successful: 1) paraquat (1,1’-dimethyl-4,4’-bipyridinium ion) + oryzalin (3,5-dinitro-N4,N4-dipropylsulfanilamide) (preemergence), paraquat (ground cracking), naptalam (N-1-naphthylphthalamic acid) + dinoseb (2-sec-butyl-4,6-dinitrophenol) (postemergence); and 2) paraquat + pendimethalin [N-(1-ethylpropyl-3,4-dimethyl-2,6-dinitrobenzenamine] (preemergence), acetochlor [2-chloro-N(ethoxymethyl)-6’-ethyl-o-acetotoluidide] + dinoseb (ground cracking), and cyanazine {2-[[4-chloro-6-(ethylamino)-s-triazine-2-yl]amino]-2-methylpropionitrile} (early postdirected spray). Both systems provided the best overall control of Texas panicum (Panicum texanumBuckl. ♯ PANTE), Florida beggarweed [Desmodium tortuosum(Sw.) DC. ♯ DEDTO], and sicklepod (Cassia obtusifoliaL. ♯ CASOB) and were acceptable for use in minimum-tillage peanut production.

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Seeding Date, Seeding Rate, and Row Spacing Affect Wheat (Triticum aestivum) and Cheat (Bromus secalinus)

Weed Technology ◽

10.1017/s0890037x0003373x ◽

1991 ◽

Vol 5 (4) ◽

pp. 707-712 ◽

Cited By ~ 15

Author(s):

Jeffrey A. Koscelny ◽

Thomas F. Peeper ◽

John B. Solie ◽

Stanley G. Solomon

Keyword(s):

Triticum Aestivum ◽

Winter Wheat ◽

Field Experiments ◽

Wheat Yield ◽

Row Spacing ◽

Infestation Level ◽

Seeding Rate ◽

Seeding Date ◽

Bromus Secalinus ◽

Winter Wheat Yield

Field experiments were conducted in Oklahoma to determine the effects of winter wheat seeding date and cheat infestation level on cultural cheat control obtained by increasing winter wheat seeding rates and decreasing row spacing. Seeding rate and row spacing interactions influenced cheat density, biomass, or seed in harvested wheat (dockage) at two of three locations. Suppressive effects on cheat of increasing wheat seeding rates and reduced row spacings were greater in wheat seeded in September than later. At two other locations, increasing seeding rate from 67 to 101 kg ha–1or reducing row spacings from 22.5 to 15 cm increased winter wheat yield over a range of cheat infestation levels.

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