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ARS Home » Southeast Area » Auburn, Alabama » Soil Dynamics Research » Research » Publications at this Location » Publication #325383
Title: Evaluation of organic cover crop termination methods: flame or fiction?

Author
item Price, Andrew
item Duzy, Leah
item MCELROY, JOSEPH - Auburn University

Submitted to: Weed Science Society of America Meeting Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: 2/8/2016
Publication Date: 2/8/2016
Citation: Price, A.J., Duzy, L.M., Mcelroy, J.S. 2016. Evaluation of organic cover crop termination methods: flame or fiction?. Weed Science Society of America Meeting Abstracts. CDROM.

Interpretive Summary:

Technical Abstract: Use of winter cover crops is an integral component of organic vegetable systems. However, timely spring termination currently relies on tillage in most instances due to time constraints. Thus, the use of conservation practices in organic systems is usually disjointed with some tillage required between crop transitions. Field experiments were conducted from autumn of 2012 through cover crop termination in spring 2014 at the Alabama Agricultural Experiment Station’s E.V. Smith Research Center at Shorter, AL to evaluate organic cover crop termination practices compared to an effective conventional standard, all managed using conservation practices including a cover crop roller-crimper. The experiment was a strip plot design with a factorial arrangement of cover crop, termination month, and termination method. Cover crops included hairy vetch, crimson clover, cereal rye, Austrian winter pea, and rape, terminated in late February, March, and April. The termination treatments applied over the entire plot included: 1) 20% vinegar solution, 2) 45% clove oil /45% cinnamon oil solution, 3) 3 mil clear plastic sheeting, 4) broadcast flame utilizing a boxed directed propane flame apparatus, and 5) 1.12 kg ae/ha glyphosate. Prior to termination application, the entire experimental area including non-treated was rolled with a cover crop roller-crimper. Cover crop termination was then evaluated one, two, and three weeks after application. In 2013, averaged over termination date, hairy vetch, Austrian winter pea, and cereal rye provided the highest biomass followed by clover and rape. Three weeks after treatment, results show that utilizing broadcast flaming was >90% effective and similar to glyphosate, except for crimson clover in which no organic treatment provided greater than 76% control due to regrowth. Clear plastic mulch terminated hairy vetch and winter peas > 90%. Vinegar and oil treatments provided little additional termination. In 2013 biomass was higher and three weeks after treatment, termination results show that all treatments were more effective than 2012 with similar trends. Thus, organic producers needing to terminate winter covers would most likely be successful using a broadcast flamer in most any winter cover or utilizing clear plastic in hairy vetch, winter peas, or cereal rye as ambient temperature increase along with solar radiation, both in combination with a roller/crimper. Commercially available vinegar and clove/cinnamon oil solutions provided little predictable termination and producers are likely to resort to tillage if no other material or practice is readily available.