The values of warm-season native perennial grasses grown for pasture or biofuel in the southern Great Plains USA

摘要

The Renewable Fuel Standard under the Energy Independence and Security Act of2007 mandated the production of 136 billion liters of ccllulosic biofuel by 2022. Switchgrass (Punicum virgatum) has been identified as a primary feedstock because it is a perennial, produces high yields and is adapted to a wide environmental range. Development of the ccllulosic biofuel industry has been slow. A reason for this slow development is lack of available feedstock driven by lack of a developed market. Rather thanconsidering switchgrass only as a dedicated biofuel feedstock, wc examined its potential both for grazing and biofuel feedstock. In a series of experiments testing yield, grazing preference and animal gain; switchgrass (cv. Alamo) was found to produce greater total yield (17696 kg/ha) than fifteen other warm season perennial grasses, was the most preferred by stocker cattle in a grazing preference study and produced average daily gains in a grazing study (0.84-1.05 kg/hd). These results demonstrate thepotential of switchgrass for both grazing and biofuel feedstock. However, the feedstock price would need to increase above $91/t before the economics of dedicated switchgrass feedstock production would surpass that of a combination of switchgrass grazingand feedstock production.