Thursday, August 9, 2007 - 2:30 PM

OOS 40-4: Biofuel production from switchgrass (Panicum virgatum L.)

Rob Mitchell and Kenneth P. Vogel. USDA-ARS and University of Nebraska

Switchgrass has been identified as an important perennial Bioenergy crop in the central US. An important aspect of the economic viability of switchgrass for Bioenergy is establishing a stand that produces harvestable yield during the seeding year. Successful stand establishment requires selecting the proper cultivar for the plant adaptation region, purchasing quality seed, properly calibrating the drill to dispense at least 225 pure live seed m-2, planting seed 10 mm deep in a firm seedbed, and applying herbicides to control grassy and broad leaf weeds. On 10 farms in Nebraska, South Dakota, and North Dakota, pre-emergent herbicide application to control annual grasses in the establishment year had 36% less feedstock costs than fields with no herbicide treatment or only a broadleaf herbicide application. Feedstock costs were 34% lower for farmers with previous experience growing switchgrass than for farmers with no switchgrass experience. Better establishment conditions east of 98.5° W. Longitude resulted in fields with 31% less feedstock costs than fields west of 98.5° W. Longitude. After harvest, poor storage conditions resulted in storage losses as high as 24% in a single year. Areas needing additional research include fertilizer requirements other than N, determining the stage of maturity that optimizes biomass production and composition for ethanol yield, determining economical methods for storing switchgrass to reduce storage losses, and the potential to develop cultivars specifically for high ethanol yields. Switchgrass is an economically viable and sustainable feedstock for the central USA east of 100o W. Longitude to reduce our dependence on fossil fuels.