Cropping system and landscape characteristics influence long-term grain crop profitability

Authors: CONWAY, L - University Of Missouri; YOST, M - Utah State University; Kitchen, Newell; Sudduth, Kenneth - Ken; MASSEY, R - University Of Missouri; Sadler, Edward

Submitted to: Agrosystems, Geosciences & Environment
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 7/27/2020
Publication Date: 9/25/2020
Citation: Conway, L.S., Yost, M.A., Kitchen, N.R., Sudduth, K.A., Massey, R.E., Sadler, E.J. 2020. Cropping system and landscape characteristics influence long-term grain crop profitability. Agrosystems, Geosciences & Environment. 3(1). Article e20099. https://doi.org/10.1002/agg2.20099.
DOI: https://doi.org/10.1002/agg2.20099

Interpretive Summary: Many cropping systems in the Midwestern United States consist of an annual corn-soybean rotation. Oftentimes, these systems have high input costs due to tillage and/or high rates of agrichemicals. Previous research has found reductions in topsoil loss and improvements in soil health by implementing no-tillage, extending crop rotations, and including cover crops. However, converting from a standard corn-soybean rotation to a more conservation-based system that includes an extended rotation, no-tillage, cover crops, and reduced inputs must be profitable for growers to adopt. Therefore, research was conducted to determine how cropping systems that vary in crop and soil management, landscape position, and topsoil depth affect profitability on claypan soil. The study was conducted near Centralia, MO from 1991 to 2009 on large plots included in the Long-Term Agroecosystem Network. Three cropping systems (tilled corn-soybean; no-tilled corn-soybean; no-tilled corn-soybean-wheat with cover crops) were evaluated across three landscape positions (summit, backslope, and footslope). Results across landscape positions indicated that both no-tillage cropping systems produced a greater net return than the system including tillage. Corn was most profitable in the no-tillage corn-soybean system, while soybean net return was similar among no-tillage systems. These findings indicate the potential to improve soybean profit with no-tillage. However, adjustments are needed before the corn-soybean-wheat rotation with cover crops is more profitable than the no-tilled corn-soybean system. This information will help growers and consultants improve cropping system management plans on claypan soil fields.

Technical Abstract: Converting from standard tillage or no-tillage cropping systems (CS) to a more conservation-based CS that includes no-tillage, cover crops, and reduced agrichemical inputs must be profitable for large-scale adoption. Therefore, research was conducted at the Central Mississippi River Basin site of the USDA Long-Term Agroecosystem Research Network from 1991 to 2009 to determine how CS, landscape position (LP), and depth to claypan (DTC) affected net economic return among different CS. Treatments consisted of three CS {MTCS, mulch till corn (Zea mays L.)-soybean [Glycine max (L.) Merr.]; NTCS, no-till corn-soybean; NTCSW, no-till corn-soybean-wheat (Triticum aestivum L.)-cover crop} and three LP (summit, backslope, and footslope). Within CS, each LP had a distinct DTC. Results for all crops showed that LP affected net return across CS, with the greatest net return occurring on summit and footslopes. Across LP, net return in NTCS was $252 and $119/(ha yr) greater than MTCS and NTCSW, respectively. Net return of corn in MTCS and NTCSW was negative, while corn in NTCS averaged $97/(ha yr). Only corn in NTCS had a positive linear response of net return to DTC. Soybean was much more profitable than corn, and both NTCS and NTCSW were less influenced by LP and had at least $252/(ha yr) greater return for soybean than did MTCS across LP. Results suggest that converting from a MT to NTCS would have large positive impacts on reducing within-field variability and increasing profitability in the region, and modifications are needed before NTCSW is profitable for corn.