Corn Stover Harvesting: Potential Supply and Water Quality Implications

Abstract

Corn stover is a likely bioenergy feedstock, but whether farmers would find harvesting stover profitable depends on its price as well as on the prices of corn and other agricultural commodities. We analyze the potential supply of corn stover and the associated changes in crop rotations and tillage practices for a major US corn production region, the state of Iowa. Using remote-sensing crop-cover maps and digitized soils data as inputs to integrated economic, geographical, and environmental models, we simulate the land use changes in response to alternative crop and corn stover prices. The ensuing changes in soil erosion, nitrogen runoff, and phosphorus runoff are predicted with the Environmental Policy Integrated Climate model. We find that the amount and the location of corn stover available for sale at a viable stover market are greatly influenced by the primary product (crop) markets. High corn stover prices can significantly affect land use, which in turn may incur significant soil erosion as well as nitrogen and phosphorus runoff in the region.