Management of High-Residue Cover Crops in a Conservation Tillage Organic Vegetable On-Farm Setting

A three year on-farm conservation-tillage experiment was initiated in fall of 2008 at Randle Farm LLC, located in Auburn, AL. Our objective was to evaluate and demonstrate implementation of tenable conservation vegetable production practices using high amounts of cover crop residues that reduce soil erosion, improve soil productivity and quality, reduce energy costs, and promote farm profitability. Cereal rye, crimson clover, and a rye and crimson clover mixture were evaluated as cover crops; these were terminated using either a prototype two-stage roller/crimper alone or followed by an application of 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 in the spring prior to crop establishment. A winter fallow conventional tillage system was included for comparison. Watermelons, cantaloupes, and okra then were transplanted into each cover crop and termination treatment combination in mid-May, utilizing a modified transplanter equipped with a custom fitted subsoiling shank and row cleaners to alleviate soil compaction and facilitate transplanting. In all years, all cover crop treatments exceeded 4000 kg ha−1and in 2009 and 2011, exceeded 6000 kg ha−1. At 21 days after termination in 2010 when the slowest termination occurred, higher termination rates were obtained for cereal rye (95% to 96%) followed by lower termination rates for the clover/rye mixture (83% to 85%); the lowest termination rates were obtained for crimson clover (66% to 68%). Commercially available cinnamon/clove oil solution provided little cover crop termination above that provided by a roller crimper alone. Volumetric soil moisture content for rolled/crimped cover crops was consistently higher compared to the conventional system, indicating that flattened and desiccated cover crop residue provided water conservation. In 2010 and 2011, yields for cantaloupe, okra, and watermelons were consistently higher for the conventional system compared with no-till system with cover crops likely due to weed cultivation limitations and insect pressure. Future studies need to focus on weed control and integrated pest management.

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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.

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Influence of legume cover crops and conservation tillage on soil populations of selected fungal genera

Canadian Journal of Microbiology ◽

10.1139/m88-038 ◽

1988 ◽

Vol 34 (3) ◽

pp. 201-206 ◽

Cited By ~ 9

Author(s):

C. S. Rothrock ◽

W. L. Hargrove

Keyword(s):

Cover Crops ◽

Cover Crop ◽

Conservation Tillage ◽

Field Studies ◽

Macrophomina Phaseolina ◽

Hairy Vetch ◽

Fusarium Spp ◽

Crimson Clover ◽

Legume Cover Crops ◽

Legume Cover Crop

The influence of winter legume cover crops and of tillage on soil populations of fungal genera containing plant pathogenic species in the subsequent summer sorghum crop were examined in field studies. Legume cover crops significantly increased populations of Pythium spp. throughout the sorghum crop compared with a rye cover crop or no cover crop. This stimulation of the populations of Pythium spp. was not solely due to colonization of cover-crop residue, as populations were significantly greater at the time the legume cover crop was desiccated. Removal of aboveground residue generally decreased populations of Pythium spp. in soil. Incorporation of residue by tillage increased populations of Pythium spp. at some sampling dates. Legumes differed in the magnitude of stimulation, with hairy vetch stimulating Pythium spp. more than crimson clover. Cover crop treatments did not consistently influence soil populations of Fusarium spp., Rhizoctonia solani, Rhizoctonia-like binucleate fungi, or Macrophomina phaseolina. Macrophomina phaseolina populations were significantly greater under no tillage.

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Evaluation of Chemical Termination Options for Cover Crops

Weed Technology ◽

10.1017/wet.2017.113 ◽

2018 ◽

Vol 32 (3) ◽

pp. 227-235 ◽

Cited By ~ 7

Author(s):

Matheus G. Palhano ◽

Jason K. Norsworthy ◽

Tom Barber

Keyword(s):

Cover Crops ◽

Cover Crop ◽

Agricultural Research ◽

Yield Potential ◽

Crop Acreage ◽

Potential Cost ◽

Cereal Rye ◽

Crimson Clover ◽

Legume Cover Crops ◽

And Control

AbstractCover crop acreage has substantially increased over the last few years due to the intent of growers to capitalize on federal conservation payments and incorporate sustainable practices into agricultural systems. Despite all the known benefits, widespread adoption of cover crops still remains limited due to potential cost and management requirements. Cover crop termination is crucial, because a poorly controlled cover crop can become a weed and lessen the yield potential of the current cash crop. A field study was conducted in fall 2015 and 2016 at the Arkansas Agricultural Research and Extension Center in Fayetteville to evaluate preplant herbicide options for terminating cover crops. Glyphosate-containing treatments controlled 97% to 100% of cereal rye and wheat, but glyphosate alone controlled less than 57% of legume cover crops. The most effective way to control hairy vetch, Austrian winterpea, and crimson clover with glyphosate resulted from mixtures of glyphosate with glufosinate, 2,4-D, and dicamba. Higher rates of auxin herbicides improved control in these mixtures. Glufosinate alone or in mixture controlled legume cover crops 81% or more. Paraquat plus metribuzin was effective in terminating both cereal and legume cover crops, with control of cereal cover crops ranging from 87% to 97% and control of legumes ranging from 90% to 96%. None of these herbicides or mixtures adequately controlled rapeseed.

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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.

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Herbicide Programs for the Termination of Various Cover Crop Species

Weed Technology ◽

10.1017/wet.2017.20 ◽

2017 ◽

Vol 31 (4) ◽

pp. 514-522 ◽

Cited By ~ 5

Author(s):

Cody D. Cornelius ◽

Kevin W. Bradley

Keyword(s):

Cover Crops ◽

Cover Crop ◽

Field Experiments ◽

Crop Yields ◽

Production Systems ◽

Annual Ryegrass ◽

Crop Species ◽

Cereal Rye ◽

Crimson Clover ◽

Herbicide Treatments

The recent interest in cover crops as a component of Midwest corn and soybean production systems has led to a greater need to understand the most effective herbicide treatments for cover crop termination prior to planting corn or soybean. Previous research has shown that certain cover crop species can significantly reduce subsequent cash crop yields if not completely terminated. Two field experiments were conducted in 2013, 2014, and 2015 to determine the most effective herbicide program for the termination of winter wheat, cereal rye, crimson clover, Austrian winter pea, annual ryegrass, and hairy vetch; and cover crops were terminated in early April or early May. Visual control and above ground biomass reduction was determined 28 d after application (DAA). Control of grass cover crop species was often best with glyphosate alone or combined with 2,4-D, dicamba, or saflufenacil. The most consistent control of broadleaf cover crops occurred following treatment with glyphosate +2,4-D, dicamba, or saflufenacil. In general, control of cover crops was higher with early April applications compared to early May. In a separate study, control of 15-, 25-, and 75-cm tall annual ryegrass was highest with glyphosate at 2.8 kg ha−1or glyphosate at 1.4 kg ha−1plus clethodim at 0.136 kgha−1. Paraquat- or glufosinate-containing treatments did not provide adequate annual ryegrass control. For practitioners who desire higher levels of cover crop biomass, these results indicate that adequate levels of cover crop control can still be achieved in the late spring with certain herbicide treatments. But it is important to consider cover crop termination well in advance to ensure the most effective herbicide or herbicide combinations are used and the products are applied at the appropriate stage.

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Evaluating Cover Crops and Herbicides for Glyphosate-Resistant Palmer Amaranth (Amaranthus palmeri) Control in Cotton

Weed Technology ◽

10.1614/wt-d-15-00113.1 ◽

2016 ◽

Vol 30 (2) ◽

pp. 415-422 ◽

Cited By ~ 18

Author(s):

Matthew S. Wiggins ◽

Robert M. Hayes ◽

Lawrence E. Steckel

Keyword(s):

Cover Crops ◽

Cover Crop ◽

The United States ◽

Palmer Amaranth ◽

Amaranthus Palmeri ◽

Hairy Vetch ◽

Cereal Rye ◽

Crimson Clover ◽

Legume Cover Crops ◽

Herbicide Programs

Glyphosate-resistant (GR) weeds, especially GR Palmer amaranth, are very problematic in cotton-producing areas of the midsouthern region of the United States. Growers rely heavily on PRE residual herbicides to control Palmer amaranth since few effective POST options exist. Interest in integrating high-residue cover crops with existing herbicide programs to combat GR weeds has increased. Research was conducted in 2013 and 2014 in Tennessee to evaluate GR Palmer amaranth control when integrating cover crops and PRE residual herbicides. Cereal rye, crimson clover, hairy vetch, winter wheat, and combinations of one grass plus one legume were compared with winter weeds without a cover crop followed by fluometuron or acetochlor applied PRE. Biomass of cover crops was determined prior to termination 3 wk before planting. Combinations of grass and legume cover crops accumulated the most biomass (> 3,500 kg ha−1) but by 28 d after application (DAA) the cereal rye and wheat provided the best Palmer amaranth control. Crimson clover and hairy vetch treatments had the greatest number of Palmer amaranth. These cereal and legume blends reduced Palmer amaranth emergence by half compared to non–cover-treated areas. Fluometuron and acetochlor controlled Palmer amaranth 95 and 89%, respectively, at 14 DAA and 54 and 62%, respectively, at 28 DAA. Cover crops in combination with a PRE herbicide did not adequately control Palmer amaranth.

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Cover Crop and Postemergence Herbicide Integration for Palmer amaranth Control in Cotton

Weed Technology ◽

10.1017/wet.2017.10 ◽

2017 ◽

Vol 31 (3) ◽

pp. 348-355 ◽

Cited By ~ 3

Author(s):

Matthew S. Wiggins ◽

Robert M. Hayes ◽

Robert L. Nichols ◽

Lawrence E. Steckel

Keyword(s):

Cover Crops ◽

Weed Management ◽

Cover Crop ◽

Field Experiments ◽

Palmer Amaranth ◽

Cereal Rye ◽

Crimson Clover ◽

Annual Grasses ◽

Winter Annual ◽

Hand Weeding

Field experiments were conducted to evaluate the integration of cover crops and POST herbicides to control glyphosate-resistant Palmer amaranth in cotton. The winter-annual grasses accumulated the greatest amount of biomass and provided the most Palmer amaranth control. The estimates for the logistic regression would indicate that 1540 kg ha−1would delay Palmer amaranth emerging and growing to 10 cm by an estimated 16.5 days. The Palmer amaranth that emerged in the cereal rye and wheat cover crop treatments took a longer time to reach 10 cm compared to the hairy vetch and crimson clover treatments. POST herbicides were needed for adequate control of Palmer amaranth. The glufosinate-based weed control system provided greater control (75% vs 31%) of Palmer amaranth than did the glyphosate system. These results indicate that a POST only herbicide weed management system did not provide sufficient control of Palmer amaranth, even when used in conjunction with cover crops that produced a moderate level of biomass. Therefore, future recommendations for GR Palmer amaranth control will include integrating cover crops with PRE herbicides, overlaying residual herbicides in-season, timely POST herbicide applications, and hand weeding in order to achieve season-long control of this pest.

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Effectiveness of Cover Crop Termination Methods on No-Till Cantaloupe

Agriculture ◽

10.3390/agriculture12010066 ◽

2022 ◽

Vol 12 (1) ◽

pp. 66

Author(s):

Ted S. Kornecki ◽

Corey M. Kichler

Keyword(s):

Cover Crops ◽

Cover Crop ◽

Hairy Vetch ◽

Two Stage ◽

Cereal Rye ◽

Crimson Clover ◽

Termination Rate ◽

Growing Seasons ◽

No Till ◽

Crop Planting

In a no-till system, there are many different methods available for terminating cover crops. Mechanical termination, utilizing rolling and crimping technology, is one method that injures the plant without cutting the stems. Another popular and commercially available method is mowing, but this can cause problems with cover crop re-growth and loose residue interfering with the planter during cash crop planting. A field experiment was conducted over three growing seasons in northern Alabama to determine the effects of different cover crops and termination methods on cantaloupe yield in a no-till system. Crimson clover, cereal rye, and hairy vetch cover crops were terminated using two different roller-crimpers, including a two-stage roller-crimper for four-wheel tractors and a powered roller-crimper for a two-wheel walk-behind tractor. Cover crop termination rates were evaluated one, two, and three weeks after termination. Three weeks after rolling, a higher termination rate was found for flail mowing (92%) compared to lower termination rates for a two-stage roller (86%) and powered roller-crimper (85%), while the control termination rate was only 49%. There were no significant differences in cantaloupe yield among the rolling treatments, which averaged 38,666 kg ha−1. However, yields were higher for cereal rye and hairy vetch cover crops (41,785 kg ha−1 and 42,000 kg ha−1) compared to crimson clover (32,213 kg ha−1).

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Net returns and risk for cover crop use in Alabama tomato production

Renewable Agriculture and Food Systems ◽

10.1017/s1742170513000227 ◽

2013 ◽

Vol 29 (4) ◽

pp. 334-344 ◽

Cited By ~ 2

Author(s):

Leah M. Duzy ◽

Ted S. Kornecki ◽

Kipling S. Balkcom ◽

Francisco J. Arriaga

Keyword(s):

Cover Crops ◽

Production System ◽

Cover Crop ◽

Conservation Tillage ◽

Weather Conditions ◽

Plastic Mulch ◽

Fresh Market ◽

Tomato Production ◽

Crimson Clover ◽

Net Returns

AbstractTomato (Solanum lycopersicumL.) producers are faced with uncertain yields and prices, and utilizing a production system that will reduce risk while maintaining yield may keep tomato producers economically sustainable into the future. A conservation tillage production system with high biomass cover crops may be an economically viable alternative for tomato producers in Alabama. The objective of this study was to compare the economics of alternative production systems using different cover crops, such as cereal rye (Secale cerealeL.) and crimson clover (Trifolium incarnatumL.), and different subsoiler shanks for fresh-market tomato production relative to a commonly used plastic mulch system to determine the preferred treatment. Gross revenues and net returns from tomato production using a rye cover crop were higher than tomato production using plastic mulch in 2 of the 4 years. For the clover cover crop, gross revenues and net returns were higher in 1 out of the 4 years. Under tomato prices and weather conditions observed during 2005–2008, the preferred treatment for a risk neutral producer was planting tomatoes into a rye cover crop with a wide shank. For a strongly risk averse producer, all cover crop treatments were preferred to plastic mulch. The use of a cover crop in tomato production has the potential to be an equally profitable, less risky alternative to plastic mulch in Alabama.

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Cover crop response to residual herbicides in peanut-cotton rotation

Weed Technology ◽

10.1017/wet.2020.5 ◽

2020 ◽

Vol 34 (4) ◽

pp. 534-539

Author(s):

Katilyn J. Price ◽

Xiao Li ◽

Andrew Price

Keyword(s):

Cover Crops ◽

Cover Crop ◽

Growth Parameters ◽

Common Vetch ◽

Crop Species ◽

Cereal Rye ◽

Crimson Clover ◽

Crop Establishment ◽

Initial Injury ◽

Chlorimuron Ethyl

AbstractCover crops can provide many benefits to peanut and cotton crops planted in rotation including suppressing weeds, conserving soil moisture after termination, increasing soil organic matter, and reducing soil erosion. However, herbicide carryover can affect cover crop establishment. The objective of this study was to investigate the responses of 6 cover crops (daikon radish, cereal rye, oat, crimson clover, winter wheat, and common vetch) to 12 soil residual herbicides. A multiyear (2016–2018), multilocation study was conducted in Macon and Henry counties, Alabama. Herbicide treatments included S-metolachlor, acetochlor, pyroxasulfone, diclosulam, imazapic, chlorimuron-ethyl, bentazon plus acifluorfen, pyrithiobac-sodium, trifloxysulfuron-sodium, diuron, prometryn, and flumioxazin, each applied at 10% of the full-labeled rate. At 42 to 52 and 145 to 149 d after planting (DAP), cover crop plant heights and stand counts were evaluated, as was biomass at 145 to 149 DAP. Treatments varied from year to year but not locations. In 2016, significant stand reductions (P ≤ 0.10) of 36% to 43% in rye and 44% to 75% in wheat were observed at 48 to 52 DAP for S-metolachlor, acetochlor, pyroxasulfone, imazapic, and bentazon plus acifluorfen compared with nontreated plants. Vetch had stand reductions ranging from 14% to 80% for all treatments 50 DAP except for plants treated with prometryn. S-metolachlor, pyroxasulfone, and acetochlor reduced stands of rye, wheat, and vetch more than any other herbicides. In 2017, at 147 to 149 DAP, clover stands were reduced by 29% with diclosulam and by 38% with trifloxysulfuron-sodium. Similarly, radish stands were reduced by 64% with diclosulam treatment. No significant biomass reductions were observed for any cover crop species either year. Oat showed the most tolerance with no treatments reducing any growth parameters either year. Although initial injury and stunting may occur, biomass at termination of cover crops were not affected by herbicide residues evaluated in this study.

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