Crop yield and economics of cropping systems involving different rotations, tillage, and cover crops

Diversified cropping systems integrated with winter cover crops (CCs) and no-till (NT) systems can provide substantial soil conservation benefits in the midwestern Corn Belt of the United States, but there is uncertainty on how these practices affect producer profits. This study compared crop yield and economic performance from cropping systems that featured three crop rotations: corn (Zea mays L.)–soybean (Glycine max [L.] Merr.; two-year), corn–soybean–oat (Avena sativa L.; three-year), and corn–soybean–oat–winter wheat (Triticum aestivum L.; four-year); two tillage systems: NT and conventional-till (CT); and two cover cropping managements: CC and no-cover crop. Tillage and rotation treatments were established in 1991 whereas cover cropping was introduced in 2013, so data from 2014 through 2018 were used for the yield and economic comparisons. Over the study period, the NT system reduced the corn yield across all rotations but increased the soybean yield under two-year rotation as compared to the CT system. Hence, both tillage systems were economically equivalent, whereby the NT system improved benefit-cost ratio as compared to the CT system. In our study, while CC in its short term did not contribute to yield and overall economic benefits, we observed highest gross revenue and second-best net returns from two-year CC plots under the NT system as compared to all other cropping systems. When compared to two-year rotations, diverse crop rotations (three- and four-year) increased the corn and soybean yields and associated profits yet compromised overall profitability due to the lower profits of small grains. It is important to identify other profitable crops that are beneficial for soils and the environment to diversify the corn–soybean rotations.