Influence of Various Cover Crop Species on Winter and Summer Annual Weed Emergence in Soybean

Field experiments were conducted in 2013, 2014, and 2015 in Columbia and Moberly, Missouri to determine the effects of cereal rye, Italian ryegrass, winter wheat, winter oat, crimson clover, Austrian winterpea, hairy vetch, oilseed radish, and cereal rye plus hairy vetch on winter and summer annual weed emergence in soybean. For comparison purposes, each experiment in each year included a Fall PRE, Spring PRE without residual, and Spring PRE residual herbicide programs. Cereal rye and cereal rye plus hairy vetch reduced winter annual weed emergence by 72 and 68%, respectively, but were not comparable to the Fall PRE which reduced winter annual weed emergence by 99%. The following spring, early-season waterhemp emergence was similar among treatments of cereal rye, cereal rye plus hairy vetch, and the Spring PRE residual herbicide program. In contrast, all cover crop species other than Italian ryegrass reduced late season waterhemp emergence between 21 and 40%, but were not comparable to the Spring PRE residual herbicide program, which reduced late season waterhemp emergence by 97%. All other summer annual weeds excluding waterhemp showed a similar response among cover crop and herbicide treatments. Overall, results from this experiment indicate that certain cover crops are able to suppress winter and summer annual weed emergence, but not to the extent of soil-applied residual herbicides.

Download Full-text

Carryover of Common Corn and Soybean Herbicides to Various Cover Crop Species

Weed Technology ◽

10.1614/wt-d-16-00062.1 ◽

2017 ◽

Vol 31 (1) ◽

pp. 21-31 ◽

Cited By ~ 19

Author(s):

Cody D. Cornelius ◽

Kevin W. Bradley

Keyword(s):

Cover Crops ◽

Cover Crop ◽

Production Systems ◽

Italian Ryegrass ◽

Hairy Vetch ◽

Crop Species ◽

Cereal Rye ◽

Crimson Clover ◽

Crop Establishment ◽

Biomass Reduction

The recent interest in cover crops as component of Midwest corn and soybean production systems has led to the need for additional research, including the effects of residual corn and soybean herbicide treatments on fall cover crop establishment. Field studies were conducted in 2013, 2014, and 2015 in Columbia, Missouri to investigate the effects of common residual herbicides applied in corn and soybean on establishment of winter wheat, tillage radish, cereal rye, crimson clover, winter oat, Austrian winter pea, Italian ryegrass, and hairy vetch. Cover crops were evaluated for stand and biomass reduction 28 d after emergence (DAE). Rainfall from herbicide application to cover crop seeding date was much greater in 2014 and 2015, which resulted in less carryover in these years compared to 2013. When averaged across all herbicides evaluated in these experiments, the general order of sensitivity of cover crops to herbicide carryover, from greatest to least was Austrian winter pea=crimson clover>oilseed radish>Italian ryegrass>hairy vetch>wheat >winter oat>cereal rye. Cereal rye had the fewest instances of biomass or stand reduction with only four out of the 27 herbicides adversely effecting establishment. Pyroxasulfone consistently reduced Italian ryegrass and winter oat biomass at least 67% in both the corn and soybean experiments. In the soybean experiment, imazethapyr- and fomesafen-containing products resulted in severe stand and biomass reduction in both years while flumetsulam-containing products resulted in the greatest carryover symptoms in the corn experiment. Results from these experiments suggest that several commonly used corn and soybean herbicides have the potential to hinder cover crop establishment, but the severity of damage will depend on weather, cover crop species, and the specific herbicide combination.

Download Full-text

Integration of residual herbicides with cover crop termination in soybean

Weed Technology ◽

10.1017/wet.2019.111 ◽

2019 ◽

Vol 34 (1) ◽

pp. 11-18 ◽

Cited By ~ 2

Author(s):

Derek M. Whalen ◽

Lovreet S. Shergill ◽

Lyle P. Kinne ◽

Mandy D. Bish ◽

Kevin W. Bradley

Keyword(s):

Weed Control ◽

Cover Crops ◽

Cover Crop ◽

Biomass Accumulation ◽

Field Studies ◽

Italian Ryegrass ◽

Cereal Rye ◽

Herbicide Treatments ◽

Residual Herbicide ◽

Herbicide Programs

AbstractCover crops have increased in popularity in midwestern U.S. corn and soybean systems in recent years. However, little research has been conducted to evaluate how cover crops and residual herbicides are effectively integrated together for weed control in a soybean production system. Field studies were conducted in 2016 and 2017 to evaluate summer annual weed control and to determine the effect of cover crop biomass on residual herbicide reaching the soil. The herbicide treatments consisted of preplant (PP) applications of glyphosate plus 2,4-D with or without sulfentrazone plus chlorimuron at two different timings, 21 and 7 d prior to soybean planting (DPP). Cover crops evaluated included winter vetch, cereal rye, Italian ryegrass, oat, Austrian winter pea, winter wheat, and a winter vetch plus cereal rye mixture. Herbicide treatments were applied to tilled and nontilled soil without cover crop for comparison. The tillage treatment resulted in low weed biomass at all collection intervals after both application timings, which corresponded to tilled soil having the highest sulfentrazone concentration (171 ng g−1) compared with all cover crop treatments. When applied PP, herbicide treatments applied 21 DPP with sulfentrazone had greater weed (93%) and waterhemp (89%) control than when applied 7 DPP (60% and 69%, respectively). When applied POST, herbicide treatments with a residual herbicide resulted in greater weed and waterhemp control at 7 DPP (83% and 77%, respectively) than at 21 DPP (74% and 61%, respectively). Herbicide programs that included a residual herbicide had the highest soybean yields (≥3,403 kg ha−1). Results from this study indicate that residual herbicides can be effectively integrated either PP or POST in conjunction with cover crop termination applications, but termination timing and biomass accumulation will affect the amount of sulfentrazone reaching the soil.

Download Full-text

Evaluation of Organic Spring Cover Crop Termination Practices to Enhance Rolling/Crimping

Agronomy ◽

10.3390/agronomy9090519 ◽

2019 ◽

Vol 9 (9) ◽

pp. 519

Author(s):

Price ◽

Duzy ◽

McElroy ◽

Keyword(s):

Cover Crop ◽

Conservation Tillage ◽

The United States ◽

Clove Oil ◽

Hairy Vetch ◽

Brassica Napus L ◽

Crop Species ◽

Cereal Rye ◽

Crimson Clover ◽

Clear Plastic

With organic farming hectarage and cover crop interest increasing throughout the United States, effectively timed cover crop termination practices are needed that can be utilized in organic conservation tillage production systems. Four commercially available termination treatments approved by Organic Materials Review Institute (OMRI) were evaluated, immediately following mechanical termination with a cover crop roller/crimper and compared to a synthetic herbicide termination to access termination rates. Treatments included rolling/crimping followed by (1) 20% vinegar solution (28 L a.i. ha−1 acetic acid), (2) 2.5 L a.i. ha−1 45% cinnamon (Cinnamomum verum L.) oil (cinnamaldehyde, eugenol, eugenol acetate)/45% clove oil (eugenol, acetyl eugenol, caryophyllene) mixture, (3) 0.15 mm clear polyethylene sheeting applied with edges manually tucked into the soil for 28 days over the entire plot area (clear plastic), (4) broadcast flame emitting 1100 °C applied at 1.2 k/h (flame), (5) glyphosate applied at 1.12 kg a.i. ha−1 (this non-OMRI-approved, non-organic conservation tillage cover crop termination standard practice was included to help ascertain desiccation, regrowth, and economics), and (6) a non-treated control. Five cover crop species were evaluated: (1) hairy vetch (Vicia villosa Roth), (2) crimson clover (Trifolium incarnatum L.), (3) cereal rye (Secale cereale L.), (4) Austrian winter pea (Pisum sativum L.), and (5) rape (Brassica napus L.). Three termination timings occurred at four-week intervals beginning mid-March each year. In April or May, organic producers are most likely to be successful using a roller crimper as either a broadcast flamer for terminating all winter covers evaluated, or utilizing clear plastic for hairy vetch, winter peas, and cereal rye. Ineffectiveness and regrowth concerns following cover crop termination in March are substantial. Commercially available vinegar and cinnamon/clove oil solutions provided little predictable termination, and producers attempting to use these OMRI-approved products will likely resort to cover crop incorporation, or mowing, to terminate covers if no other practice is readily available.

Download Full-text

Response of broadleaf and grass cover crop species to soil residues of glyphosate and aminomethylphosphonic acid (AMPA)

Weed Technology ◽

10.1017/wet.2021.77 ◽

2021 ◽

pp. 1-25

Author(s):

Zahoor A. Ganie ◽

Amit J. Jhala

Keyword(s):

Seed Germination ◽

Cover Crops ◽

Cover Crop ◽

Hairy Vetch ◽

Crop Species ◽

Cereal Rye ◽

Crimson Clover ◽

Aminomethylphosphonic Acid ◽

Loam Soil ◽

The Impact

Abstract Glyphosate is the most widely used herbicide in the United States; however, concern about increasing residues of glyphosate and its metabolite aminomethylphosphonic acid (AMPA) in soil is escalating. There is a lack of scientific literature examining the response of cover crops to soil residues of glyphosate or AMPA. The objectives of this study were to evaluate the impact of glyphosate or AMPA residues in silty clay loam soil on emergence, growth, and biomass of cover crops, including cereal rye, crimson clover, field pea, hairy vetch, and winter wheat, as well as their germination in a 0.07% (0.7 g/L) solution of AMPA or glyphosate. Greenhouse studies were conducted at the University of Nebraska-Lincoln to determine the dose response of broadleaf and grass cover crops to soil-applied glyphosate or AMPA. The results indicated that soil treated with glyphosate or AMPA up to 105 mg ae kg–1 of soil had no effect on the emergence, growth, above-ground biomass, and root biomass of any of the cover crop species tested. To evaluate the impact of AMPA or glyphosate on the seed germination of cover crop species, seeds were soaked in petri plates filled with a 0.7 g L−1 solution of AMPA or glyphosate. There was no effect of AMPA on seed germination of any of the cover crop species tested. Seed germination of crimson clover and field pea in a 0.7 g L−1 solution of glyphosate was comparable to the nontreated control; however, the germination of cereal rye, hairy vetch, and winter wheat was reduced by 48%, 75%, and 66%, respectively, compared to the nontreated control. The results suggested that glyphosate or AMPA up to 105 mg ae kg–1 in silt clay loam soil is unlikely to cause any negative effect on the evaluated cover crop species.

Download Full-text

Sensitivity and Likelihood of Residual Herbicide Carryover to Cover Crops

Weed Technology ◽

10.1017/wet.2018.7 ◽

2018 ◽

Vol 32 (3) ◽

pp. 236-243 ◽

Cited By ~ 5

Author(s):

Matheus G. Palhano ◽

Jason K. Norsworthy ◽

Tom Barber

Keyword(s):

Biomass Production ◽

Cover Crops ◽

Cover Crop ◽

Sensitivity Study ◽

Hairy Vetch ◽

Sensitivity Experiment ◽

Cereal Rye ◽

Crimson Clover ◽

Residual Herbicide ◽

Crop Planting

AbstractResearch was conducted to evaluate the sensitivity of cover crops to a low rate of soil-applied herbicides and investigate the likelihood of herbicide carryover to fall-seeded cover crops following an irrigated corn crop. In the sensitivity study, herbicides were applied at a 1/16×rate (to simulate four half-lives) 1 d after cover crop planting, whereas for the carryover study residual herbicides were applied at a 2×rate at the maximum label corn height or growth stage and cover crops sown immediately after corn harvest. In the sensitivity experiment, atrazine, diuron, fluridone, fomesafen, metribuzin, pyrithiobac, and sulfentrazone reduced emergence of the leguminous cover crops Austrian winterpea, crimson clover, and hairy vetch. However, reduced biomass production of leguminous cover crops in the spring was only observed for atrazine, fluridone, and pyrithiobac. For rapeseed, atrazine, flumioxazin, fluridone, pyrithiobac, pyroxasulfone, sulfentrazone, and tembotrione reduced emergence, but biomass production was reduced only by atrazine and fluridone. Conversely, wheat, cereal rye, barley, oats, and triticale were not affected by soil-applied herbicides. Barley was the only cereal cover crop that showed biomass reduction due to the application of flumioxazin, fluridone, mesotrione,S-metalochlor, and sulfentrazone. In the carryover study, with the exception of crimson clover, Austrian winterpea, cereal rye, hairy vetch, rapeseed, and wheat showed no negative affect on biomass production following a 2×rate of postemergence-applied residual herbicide in corn.

Download Full-text

Cover crop-based reduced tillage system influences Carabidae (Coleoptera) activity, diversity and trophic group during transition to organic production

Renewable Agriculture and Food Systems ◽

10.1017/s1742170516000466 ◽

2017 ◽

Vol 32 (6) ◽

pp. 538-551 ◽

Cited By ~ 14

Author(s):

Ariel Rivers ◽

Christina Mullen ◽

John Wallace ◽

Mary Barbercheck

Keyword(s):

Cover Crops ◽

Cover Crop ◽

Cultural Practices ◽

Reduced Tillage ◽

Hairy Vetch ◽

Crop Species ◽

Cereal Rye ◽

Activity Density ◽

Tillage System ◽

Termination Date

AbstractOrganic grain growers rely on cultural practices and biological control to regulate pests, and the implementation and timing of cultural practices can affect many characteristics of the cropping system as a habitat for natural enemies of arthropod pests. Ground beetles (Coleoptera: Carabidae) in particular are important insect and weed-seed predators, and are sensitive to crop rotations, tillage and environmental complexity. In a reduced tillage system in transition to organic management, we evaluated the effect of cover crop species and termination date, crop rotation and high residue cultivation on ground and tiger beetle (Coleoptera: Carabidae) activity-density, community composition and size and trophic groups. The 3-year experiment included a sequence of corn (Zea maysL.), soybean (Glycine max(L.) Merr.) and winter wheat (Triticum aestivumL.). A mixture of hairy vetch (Vicia villosaRoth) and triticale (xTriticosecaleWittmack) preceded corn, and cereal rye (Secale cerealeL.) preceded soybean, and each crop sequence was present in each year (full-entry). We compared three cover crop termination (and cash crop planting) dates by terminating the overwintered cover crops with a roller-crimper, and immediately or soon after, we no-till planted corn and soybean through the mat created by the rolled cover crops. In the corn and soybean phases of the rotation, we also compared inter-row cultivation as a pest management strategy to a control treatment (no inter-row cultivation in corn, and an alternative row-spacing in soybean). Wheat was planted on a single date in each year into tilled soil. Carabids were sampled using pitfall traps 2 weeks after termination of the two cover crop treatments, and in mid-June in wheat. Carabid activity-density and species richness increased across the experimental site during the 3-year transition, and community evenness across the experimental site increased by the third year. Crop species influenced carabid community composition, and by the third year, the carabid community was comparable between wheat and hairy vetch-triticale cover crop. The late cover crop termination date was positively associated with higher activity-densities of large carabids in rolled hairy vetch-triticale and rolled cereal rye; carnivorous beetles in rolled hairy vetch-triticale; and granivorous beetles in rolled cereal rye. Inter-row cultivation occurring in corn and soybean resulted in a significantly higher proportion of small beetles in the wheat phase of the rotation, with a significantly higher proportion of large beetles in wheat treatments, which had not received inter-row cultivation in corn and soybean. Results have strong implications for management during the transition to organic, including the importance of plant residue, reduced tillage and timing of cover crop termination dates for augmenting carabid populations.

Download Full-text

Biomass and Nitrogen Content of Hairy Vetch-Cereal Rye Cover Crop Mixtures as Influenced by Species Proportions

Agronomy Journal ◽

10.2134/agronj14.0462 ◽

2015 ◽

Vol 107 (6) ◽

pp. 2069-2082 ◽

Cited By ~ 42

Author(s):

Hanna J. Poffenbarger ◽

Steven B. Mirsky ◽

Raymond R. Weil ◽

Jude E. Maul ◽

Matthew Kramer ◽

...

Keyword(s):

Nitrogen Content ◽

Cover Crop ◽

Hairy Vetch ◽

Cereal Rye ◽

Species Proportions

Download Full-text

Cover Crops Suppression of Palmer Amaranth (Amaranthus palmeri) in Cotton

Weed Technology ◽

10.1017/wet.2017.97 ◽

2017 ◽

Vol 32 (1) ◽

pp. 60-65 ◽

Cited By ~ 4

Author(s):

Matheus G. Palhano ◽

Jason K. Norsworthy ◽

Tom Barber

Keyword(s):

Cover Crops ◽

Cover Crop ◽

Field Experiments ◽

Palmer Amaranth ◽

Cotton Yield ◽

Cotton Production ◽

Seed Cotton ◽

Cereal Rye ◽

Seed Cotton Yield ◽

Weed Emergence

AbstractWith the recent confirmation of protoporphyrinogen oxidase (PPO)-resistant Palmer amaranth in the US South, concern is increasing about the sustainability of weed management in cotton production systems. Cover crops can help to alleviate this problem, as they can suppress weed emergence via allelochemicals and/or a physical residue barrier. Field experiments were conducted in 2014 and 2015 at the Arkansas Agricultural Research and Extension Center to evaluate various cover crops for suppressing weed emergence and protecting cotton yield. In both years, cereal rye and wheat had the highest biomass production, whereas the amount of biomass present in spring did not differ among the remaining cover crops. All cover crops initially diminished Palmer amaranth emergence. However, cereal rye provided the greatest suppression, with 83% less emergence than in no cover crop plots. Physical suppression of Palmer amaranth and other weeds with cereal residues is probably the greatest contributor to reducing weed emergence. Seed cotton yield in the legume and rapeseed cover crop plots were similar when compared with the no cover crop treatment. The seed cotton yield collected from cereal cover crop plots was lower than from other treatments due to decreased cotton stand.

Download Full-text

Systemic Colonization by Metarhizium robertsii Enhances Cover Crop Growth

Journal of Fungi ◽

10.3390/jof6020064 ◽

2020 ◽

Vol 6 (2) ◽

pp. 64

Author(s):

Imtiaz Ahmad ◽

María del Mar Jiménez-Gasco ◽

Dawn S. Luthe ◽

Mary E. Barbercheck

Keyword(s):

Cover Crops ◽

Cover Crop ◽

Field Experiments ◽

Negative Relationship ◽

Crop Growth ◽

Above Ground Biomass ◽

Crop Species ◽

Metarhizium Robertsii ◽

Cereal Rye ◽

Ground Biomass

Fungi in the genus Metarhizium (Hypocreales: Clavicipitaceae) are insect pathogens that can establish as endophytes and can benefit their host plant. In field experiments, we observed a positive correlation between the prevalence of M. robertsii and legume cover crops, and a negative relationship with brassicaceous cover crops and with increasing proportion of cereal rye in mixtures. Here, we report the effects of endophytic M. robertsii on three cover crop species under greenhouse conditions. We inoculated seeds of Austrian winter pea (Pisum sativum L., AWP), cereal rye (Secale cereale L.), and winter canola (Brassica napus L.) with conidia of M. robertsii to assess the effects of endophytic colonization on cover crop growth. We recovered M. robertsii from 59%, 46%, and 39% of seed-inoculated AWP, cereal rye, and canola plants, respectively. Endophytic M. robertsii significantly increased height and above-ground biomass of AWP and cereal rye but did not affect chlorophyll content of any of the cover crop species. Among inoculated plants from which we recovered M. robertsii, above-ground biomass of AWP was positively correlated with the proportion of colonized root but not leaf tissue sections. Our results suggest that winter cover crops may help to conserve Metarhizium spp. in annual cropping systems.

Download Full-text

Modeling Hairy Vetch and Cereal Rye Cover Crop Decomposition and Nitrogen Release

Agronomy ◽

10.3390/agronomy10050701 ◽

2020 ◽

Vol 10 (5) ◽

pp. 701

Author(s):

Madhav Dhakal ◽

Gurbir Singh ◽

Rachel L. Cook ◽

Taylor Sievers

Keyword(s):

Cover Crop ◽

Cropping System ◽

Plant Residue ◽

Hyperbolic Model ◽

Hairy Vetch ◽

Cereal Rye ◽

Double Exponential ◽

N Release ◽

Shoot Mass ◽

Combined Data

Empirical models could help us to understand the process of plant residue decomposition and nutrient release into the soil. The objective of this study was to determine an appropriate model to describe the decomposition of hairy vetch (Vicia villosa Roth) and cereal rye (Secale cereale L.) cover crop (CC) residue and nitrogen (N) release. Data pertaining to above and belowground CC residue mass loss and N release for up to 2633 cumulative decomposition degree days (112 d) after litterbag installation were obtained from two cropping system experiments, a 1-yr study conducted in 2015 and a 2-yr study during 2017 to 2018 in the humid subtropical environment of southern IL, USA. Six exponential and two hyperbolic models were fit to percent mass and N remaining data to find the one with minimum Akaike information criterion (AIC) and residual sum of squares. Modified three-parameter single exponential and two- or three-parameter hyperbolic models best met the assumed criteria of selection for above and belowground CC residue, respectively. Fitting a double exponential model to combined data for percent mass and N remaining identified two mass and N pools, a fast and a slow pool with different rate constants. A five-parameter double exponential with an asymptote met the preset criteria and passed all tests for normally distributed population, constant variance, and independence of residuals at α = 0.05 when fit to combined data of hairy vetch shoot mass and N remaining. However, a two-parameter hyperbolic and three-parameter asymptotic hyperbolic model provided the best fit to a combined data of cereal rye shoot mass and N remaining, respectively. Both hyperbolic decay models showed a good fit for belowground mass decomposition and N release for both CCs. Cereal rye had a poorer fit than hairy vetch for mass and N remaining of both above and belowground mass. The best-selected decay models can be used to estimate the decomposition and N release rates of hairy vetch and cereal rye above and belowground residue in a similar environment.

Download Full-text