Switchgrass biomass and chemical composition for biofuel in eastern Canada

Switchgrass (Panicum virgatum L.) is one of several warm-season grasses tha t have been identified as potential biomass crops in North America A two-ye ar field study was conducted, on a free-draining sands clay loam (St. Berna rd, Typic Hapludalf), to characterize the growth and evaluate changes in bi omass accumulation and composition of switchgrass at Montreal, QC. Three cu ltivars, Cave-in-Rock, Pathfinder, and Sunburst, were grown in solid stands in a randomized complete block design. Canopy height, dry matter (DM) accu mulation and chemical composition were monitored biweekly throughout the gr owing season. Average maximum canopy heights were 192.5 cm for Cave-in-Rock . 169.9 for Pathfinder, and 177.8 for Sunburst. The respective end-of-seaso n DM yields were 12.2, 11.5, and 10.6. Mg ha(-1). Biomass production among cultivars appeared to be related to time of maturation. Nitrogen concentrat ion of DM decreased curvilinearly from 25 g kg(-1) at the beginning of the season to 5 g kg(-1) DM at season's end. Both acid-detergent fiber (ADF) an d neutral-detergent fiber (NDF) concentrations increased to a maximum early in the season, after which no changes were detected The average maximum va lues of ADF and NDF were, respectively, 647.6 and 849.0 g kg(-1) DM for Cav e-in-Rock, 669.1 and 865.2 for Pathfinder, and 661.8 and 860.9 for Sunburst . Changes in canopy height, DM accumulation, and chemical composition could all be described by predictive regression equations, These results indicat e that switchgrass has potential as a biomass crop in a short-season enviro nment.