In cooperation with DuPont Cellulosic Ethanol, the research team has conducted a large scale, multi-pass corn stover harvest on ISU Research Farms and the ISU Ag 450 Farm. Research conducted through the 2012 harvest was concentrated around modifications for the improvement ofshredder performance in throughput and stover quality. The modifications were relayed to the commercial harvest crews who modified their machines to improve stover quality and harvest rate efficiency.