Cost Analysis of Cover Crop Inclusion and Environmental Benefits in Central Illinois.

The use of cover crops (CC) in row crop agricultural systems has been shown to provide numerous environmental benefits along with increasing overall soil health. While the environmental benefits of CC are well known, the costs associated with CC inclusion must be accounted for before widespread adoption of CC can occur. Therefore, the objective of this study is to quantify the environmental benefits observed from CC and determine the potential of those benefits to offset the input costs of CC implementation. This experiment used data collected between CC planting in 2014 and cash crop harvest in 2016 from an associated study conducted at the Illinois State University Nitrogen Management Research Field Station, in Lexington, IL. Experimental treatments were fall dominated (70% fall, 30% spring) Nitrogen (N) application with and without CC and a spring dominated (20% fall, 80% spring) N application with and without CC. The chosen CC for the study was a 92% cereal rye (Secale cereal L.) and 8% daikon radish (Raphanus sativus L.) blend, and data were collected for both strip-till corn (Zea mays L.) and no-till soybeans (Glycine max L.). Different from existing attempts to model the economic value of CC, this model includes input variables that quantify the reduction of N loss through tile drainage and the return of N from CC residue after termination. Based upon data that capture the reduction in nitrate lost via subsurface drainage due to CC and the return of CC residue N to the soil solution, we estimated that CC offset their input cost by 81-85% in fall dominated N application systems and 52-116% in spring dominated N application systems. The results of this study have the potential to provide a more comprehensive assessment of CC value that will help producers make informed nitrogen and CC management decisions.