Assessing the Economic Impact of inversion tillage, cover crops, and herbicide regimes in palmer amaranth (Amaranthus palmeri) infested cotton

Authors: Duzy, Leah; Price, Andrew; Balkcom, Kipling; AULAKH, JATINDER - University Of Nebraska

Submitted to: International Journal of Agronomy
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/2/2016
Publication Date: 12/1/2016
Publication URL: http://handle.nal.usda.gov/10113/5661735
Citation: Duzy, L.M., Price, A.J., Balkcom, K.S., Aulakh, J.S. 2016. Assessing the Economic Impact of inversion tillage, cover crops, and herbicide regimes in palmer amaranth (Amaranthus palmeri) infested cotton. International Journal of Agronomy. Volume 2016, Article ID 1524389, 9 pp. http://dx.doi.org/10.1155/2016/1524389.

Interpretive Summary: Cotton producers in Alabama and across the Cotton Belt are faced with a problem that decreases yields and increases production costs: herbicide-resistant weeds. Producers are relying on production methods that raise production costs, such as additional herbicide treatments, tillage, and hand weeding. The research presented in this article investigates how tillage, cover crops, and herbicides influence net returns for cotton production in Alabama from 2009 to 2011 under pressure from Palmer amaranth. Annual net returns and net present value across all three years were compared for two tillage treatments (inversion and non-inversion tillage), three cover crops (crimson clover, cereal rye, and fallow), and three herbicide regimes (pre-emergence only, post-emergence only, pre-emergence and post-emergence). Results indicate that under heavy Palmer amaranth infestations one year of inversion tillage followed by two years of non-inversion tillage, along with a post-emergence only or a pre-emergence plus post-emergence herbicide application had the highest net returns in the first year; however, there was no economic benefit of inversion tillage, across all herbicide treatments, in 2010 and 2011. Net present values were highest for non-inversion tillage with either a clover cover crop or fallow and either a post-emergence herbicide or a combination of pre-emergence and post-emergence herbicides. Cotton producers with Palmer amaranth infestations would likely benefit from tillage and cover crops, along with herbicide applications, as part of their weed management system to increase net returns.

Technical Abstract: Cotton (Gossypium hirsutum L.) producers in Alabama and across the Cotton Belt are faced with a rapidly expanding problem that decreases yields and increases production costs: herbicide-resistant weeds. Producers are increasingly relying on production methods that raise production costs, such as additional herbicide treatments, tillage, and hand weeding. This analysis evaluated how tillage, cover crops, and herbicide regime affected net returns for cotton production in Alabama from 2009 to 2011 under pressure from Palmer amaranth (Amaranthus palmeri S. Wats.). Annual net returns and net present value across all three years were compared for two tillage treatments (inversion and non-inversion tillage), three cover crops (crimson clover [Trifolium incarnatum L.], cereal rye [Secale cereal L.], and fallow), and three herbicide regimes (PRE, POST, PRE+POST). Inversion tillage with PRE and POST herbicide applications had the largest net returns above variable treatment costs in 2009 (1111.46 US$ ha-1). In 2010 and 2011, non-inversion tillage with a PRE herbicide application had the highest net returns (835.80 US$ ha-1 and 1707.95 US$ ha-1, respectively). Results indicate that under heavy Palmer amaranth populations one year of inversion tillage followed by two years of non-inversion tillage, along with a POST or PRE+POST herbicide application had the highest net returns in the first year; however, the economic benefit of inversion tillage, across all herbicide treatments, was non-existent in 2010 and 2011. Across all treatments, net present values were highest for non-inversion tillage with either a clover cover crop or fallow and either a POST herbicide or a combination of PRE and POST herbicides. Cotton producers with Palmer amaranth infestations would likely benefit from cultural controls, in conjunction with herbicide applications, as part of their weed management system to increase net returns.