Submitted to: Extension Publications
Publication Type: Experiment Station
Publication Acceptance Date: 7/24/2012
Publication Date: 7/24/2012
Citation: Mitchell, R., Vogel, K.P., Schmer, M.R. 2012. Switchgrass (Panicum virgatum) for biofuel production. Extension Publications. http://www.extension.org/pages/26635/switchgrass-panicum-virgatum-for-biofuel-production.
Interpretive Summary: Contrary to popular belief, switchgrass is not a new or novel crop. Currently available plant materials and production practices can reliably-produce 5 tons per acre in the central Great Plains and Midwest, and 10 tons per acre in much of the Southeast. New cultivars and management practices will significantly increase yields similar to the increases that have been achieved with corn yields in the last 30 years. The availability of adequate acres of agricultural land and the profit potential provided to farmers for growing switchgrass in a region will determine the success of growing switchgrass for biomass energy. Production practices and plant materials are available to achieve sustainable and profitable biomass production, for both farmers and bio-refineries, to help meet the energy requirements of the nation and reduce our dependence on foreign oil.
Technical Abstract: Switchgrass (Panicum virgatum) is a native warm-season grass that is a leading biomass crop in the US. More than 70-years of experience with switchgrass as a hay and forage crop suggests switchgrass will be productive and sustainable on rain-fed marginal land east of the 100th Meridian. Long-term plot trials and farm-scale studies in the Great Plains and plot trials in the Great Plains, Midwest, South, and Southeast indicate switchgrass is productive, protective of the environment, and profitable for the farmer. Weed control is essential during establishment, but with good management is typically not required again. Although stands can be maintained indefinitely, stands are expected to last at least 10 years, after which time the stand will be renovated and new, higher-yielding material will be seeded on the site. Fertility requirements are well understood in most regions, with about 12 to 14 pounds of N per acre required for each ton of expected yield if the crop is allowed to completely senesce before the annual harvest. Historically, breeding and genetics research has been conducted at a limited number of locations by USDA and university scientists, but the potential bioenergy market has promoted testing by public and private entities throughout the US. Switchgrass is well-suited to marginal cropland and is an energetically and economically feasible and sustainable biomass energy crop with currently-available technology.