Cover crop impact on irrigated cotton yield and net return in the southern Great Plains

Cover crops have the potential to increase ecosystem services of cropping systems, although mixed results have been found throughout the U.S. Great Plains. Crop performance and economic returns are often used by producers to gauge the feasibility of adoption. In addition, soil moisture use by cover crops is a concern in semiarid environments. The objective of this research was to determine the impact of cover crops on cotton (Gossypium hirsutum L.) yield and economic return compared with conventional practices in pivot irrigated systems of the southern Great Plains. A 6-yr study was conducted at the Texas A&M AgriLife Chillicothe Research Station evaluating the following treatments: (i) conventional till (CT); (ii) no-till (NT); (iii) NT with winter wheat (Triticum aestivum L.) cover crop (NT-W); and (iv) NT with a multi-species cover crop mixture (NT-M). Cotton yields, expenses, and returns were determined over a 6-yr period (2013-2018). No significant treatment effect was determined for crop yield. Compared to NT, lint yields were increased 9.5% by NT-M and 9.4% by NT-W. Cover crop treatments significantly increased total costs compared to NT. However, net returns were 12% greater for NT-W and 8% greater for NT-M compared to NT. Over the 6-yr study, NT-M did not provide an agronomic or economic advantage over NT-W. Under irrigated conditions in the southern Great Plains, cover crops were implemented without negatively affecting lint yield or net returns in continuous cotton systems at seeding rates of 34 kg ha(-1).