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ARS Home » Southeast Area » Auburn, Alabama » Soil Dynamics Research » Research » Publications at this Location » Publication #370095
Research Project: Conservation Systems to Improve Production Efficiency, Reduce Risk, and Promote Sustainability

Location: Soil Dynamics Research

Title: Effect of cover crop mixture and herbicide timing on weed control in cotton

Author
item JOHNSON, ANNA - Auburn University
item Price, Andrew
item GAMBLE, AUDREY - Auburn University

Submitted to: ASA-CSSA-SSSA Annual Meeting Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: 11/8/2019
Publication Date: 11/8/2019
Citation: Johnson, A., Price, A.J., Gamble, A. 2019. Effect of cover crop mixture and herbicide timing on weed control in cotton[abstract]. ASA-CSSA-SSSA Annual Meeting. CD ROM.

Interpretive Summary:

Technical Abstract: The inclusion of winter cover crops is a common tool for integrated weed management in both conventional and conservation systems. A trial was established at E.V. Smith Research Center in Shorter, AL in November 2016 to evaluate the efficacy of several cover crop systems as an additional form of weed control in cotton. The trial consisted of twelve treatments. Cover crops included a rye (Secale cereal) treatment and a mixture of rye, oats (Avena sativa), wheat (Triticum aestivum), crimson clover (Trifolium incarnatum), and Daikon radish (Raphanus sativus) compared to winter fallow treatments. Each cover crop system was evaluated under four herbicide regimes including PRE only (pendimethalin and fomesafen), POST only (dicamba fb glyphosate), PRE+POST, and herbicide-free treatments. Cover crop biomass was measured prior to termination. Weed biomass samples and were taken in June each year, and weed control ratings were taken in early August. Pigweed control was significantly lower in all herbicide-free treatments compared to all PRE+POST treatments, and cotton lint yield was lower in the herbicide-free treatments compared to treatments with herbicide applications. Lint yield was highest in the PRE+POST treatments while herbicide-free treatments had the lowest lint yield, regardless of cover crop. Lint yield under PRE only treatments were not different from PRE+POST while POST only treatments had lower lint yield than PRE+POST treatments. Results indicate that cover crops alone will not eliminate the need for chemical weed control.