A Cost Analysis Approach to Valuing Cover Crop Environmental and Nitrogen Cycling Benefits: A Central Illinois on Farm Case Study.

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 considered before widespread CC adoption can occur. Therefore, the objective of this case study was to quantify the environmental and nitrogen (N) cycling benefits observed from CC and determine the potential of those benefits to offset the costs of CC inclusion. This experiment used data collected between CC planting in 2014 and cash crop harvest in 2017 from the Illinois State University Nitrogen Management Research Field Station, in Lexington, Illinois. In the case study, CC were integrated into two cropping systems common to Central Illinois. The cropping systems included a split application of N with the dominant portion applied in the spring with and without CC and a split N application with the dominant portion applied in the fall 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.). We estimated that environmental and nitrogen cycling benefits observed from CC resulted in an average calculated recovery of approximately 61% of the costs associated with implementing CC into the cropping systems. More specifically, the average composition of recovered costs was 34% from reductions in nitrogen loading to subsurface drainage, 57% from net N mineralization of CC residue, and 9% from erosion reduction. 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.