|NICHOLS, KRISTINE - Rodale Institute|
|TANAKA, DONALD - Retired ARS Employee|
Submitted to: ASA-CSSA-SSSA Annual Meeting Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: 7/11/2017
Publication Date: 10/22/2017
Citation: Archer, D.W., Liebig, M.A., Hendrickson, J.R., Schmer, M.R., Nichols, K.A., Tanaka, D.L. 2017. Short-term economics of late-seeded cover crops in a semi-arid environment. ASA-CSSA-SSSA Annual Meeting Abstracts. ASA-CSSA-SSSA Annual Meeting Abstracts. ASA-CSSA-SSSA Annual Meeting, October 22-25, 2017, Tampa, FL. https://doi.org/scisoc.confex.com/crops/2017am/webprogram/Paper105653.html .
Technical Abstract: While cover crops have many potential benefits, including reducing soil erosion, increasing soil organic carbon, improving nutrient cycling, reducing pest, and increasing yield and yield stability, if producers are to grow them, it is important to understand how they can be produced most cost-effectively. A field study was conducted from 2008-2011 to investigate the productivity, soil impacts, and economic performance of 19 cover crop treatments seeded after dry pea (Pisum sativum L.) harvest near Mandan, North Dakota. The cover crop treatments included seven crops in monoculture or mixtures, including proso millet (Panicum miliaceum L.), spring triticale (Triticale hexaploide Lart.), soybean [Glycine max (L.) Merr.], dry pea, sunflower (Helianthus annuus L.), winter canola (Brassica napus subsp. Rapifera), and purple top turnip (B. rapa). Eleven treatments represented cover crop mixtures ranging from binary mixtures to all seven cover crops in a mix, and one treatment served as a no cover crop control. In the year following the cover crop treatments, four response crops: spring wheat (Triticum aestivum L.), corn (Zea mays L.), soybean and dry pea were seeded in strips across each of the cover crop treatments to measure any short-term yield impacts of the cover crop treatments. This sequence was repeated on three sites. Costs for establishing cover crops were calculated based on the seed costs for the seeds included in each treatment, along with the cost for no-till planting the treatments. Response crop results showed no impact of cover crops on yields for any of the response crops, showing no short-term direct economic benefit, but also no added cost through negative production effects. Consequently, economic analysis focused not on the most profitable treatment, but on the most cost effective treatment as the treatment producing the most above ground cover crop biomass per unit cost. In addition, results showed apparent NO3-N uptake by each cover crop treatment that was correlated with biomass production. Economic analysis of this uptake also identified the most cost efficient treatments for NO3-N retention. Results showed cover crop establishment cost ranging from $53 to $106 ha-1. Cover crop biomass production and apparent NO3-N uptake varied widely between years. Overall, purple top turnip resulted in the lowest average cost per unit biomass and lowest cost per unit N uptake, at $42 Mg-1 biomass and $2.70 kg-1 N respectively.