Switchgrass is a giant, warm-season perennial grass native to North America high in cellulose, making it attractive as a biomass crop for cellulosic ethanol production in North Carolina.  The tiny seeds are planted from late April to early June.  Most of the first year’s photosynthate goes into root development in preparation for a long life span.  Therefore, very little production is expected the first year.  In subsequent years, the switchgrass is harvested after the plants go dormant, usually after the first killing frost.  Yield during the second year should be about 4 to 6 tons per acre and then averages 6 to 8 tons per acre.

Adequate phosphorus and potassium levels in the soil are important for establishing switchgrass.   However, annual maintenance application of fertilizer should be low to moderate.  It is thought that since switchgrass is a perennial species, much of the nutrients in the foliage is translocated into the crown root system.

NC State University is conducting research on the agronomics of switchgrass at the Clayton research station and on the Williamsdale Farm near Wallace, North Carolina.  The Biofuels Center has planted four varieties on the Oxford campus.

With a life span of 10 to 20 years, an average yield of 6 to 8 tons per acre, and low maintenance inputs, the economics of switchgrass production can be competitive with other crops.  With varietal improvement, switchgrass yields might approach 10 to 12 tons per acre per year.