The use of field crops as an energy source is important because of our need

1. Evaluating Switchgrass Cultivars for Biomass Potential at Low Soil FertilityGeorge T. ByrdFerrum College, Ferrum, VA 24088 Purpose Methods The use of field crops as an energy source is important because of our need • to reduce our dependency on fossil fuel • to mitigate anthropogenic atmospheric CO2 release Field Trial Location & Dates Ferrum College Agriculture Farm, Ferrum, VA (80°02’ W, 36°55’N; elevation 412 m) 2001 – 2005 Soil Type & History Hayesville loam (fine, kaolinitic, mesic Typic Kanhapludults) Pasture - previous botanical composition of tall fescue, orchardgrass, & red clover pH 5.8 with no fertilizer additions throughout the study Experimental Design A complete randomized design 4 switchgrass cultivars Alamo Cave-in-rock Kanlow Pathfinder 120 seedlings of each cultivar transplanted into the prepared soil (2001) 15 rows established, spaced 0.5 m equidistantly apart Biomass Biannual and annual potential yields from 20 randomly selected plants from each cultivar Harvested twice during 2002 & 2004 - July & October. Harvested in 2003 & 2005 in September only All harvested material removed from the area Persistence Determined annually by counting remaining living plants Switchgrass – Late September Biomass Results Yield (Mg/ha-year) Background Switchgrass (Panicum virgatum L.) has great potential as a biomass production system to generate biofuel. Switchgrass is a perennial crop that • produces well on marginal crop land. • incorporates more carbon as biomass via photosynthesis than it loses by burning as biofuel. Switchgrass as a bioenergy crop may become a successful option for producers as an alternative high value crop with reduced environmental costs. Cumulative Yield (2002-2005) Pairwise differences in potential yields of switchgrass were compared with Fisher’s protected LSD values (yields followed by different letters are different (p< 0.01) Objective Conclusions Switchgrass Persistence • To be economically suitable, two important criteria must be evaluated – production potential with minimal input and plant persistence. The objective of this study, therefore, was to • compare biomass & persistence among cultivars of switchgrass grown in infertile soil. • The cultivar Alamo produced more biomass • Persistence decreased after four years (56-63%) • Biomass without fertilizer input was only slightly lower than published data for switchgrass