Sustainability and Profitability of Residue Removal for Biofuel Use in a Water-Limited Region.

A corn residue removal research project began in 2009 on two sets of plots with 0, 25, 50, 75, and 100% stover removal levels. One plot is in eastern Kansas, and the other is an irrigated site in western Kansas. Crop grain yield is measured annually and soil organic C and bulk density are measured every other year in odd years. Thus far, there have been few instances where crop residue removal has been detrimental to corn yields. In fact, removal has led to increased crop yields at the irrigated site, where irrigation is used to double the natural precipitation each year. Corn yields are high, thus residue production has been high, and removal led to increased crop yields under irrigation in this high-yielding environment, until 2015 when the 0% removal was the highest yielding treatment, though not significantly different. At the rainfed site in eastern Kansas, differences in crop yields were observed in 2009, 2010, and 2015. In 2015, 0% removal was significantly lower yielding than all other treatments. Soil data indicates that wind erodibiility parameters increase with increasing levels of removal.