Long-term miscanthus trials achieve impressive yields, beat switchgrass

Illinois researchers recently reported results gathered from 10 years of miscanthus field trials that show significantly higher yields than switchgrass grown in side-by-side trials. The average annual yield of miscanthus grown in seven Illinois locations over an 8 to 10 year period was 10.5 tons per acre. Switchgrass yields were only 4.5 tons per acre. 

“If cellulosic comes on stream, these yields would be competitive with corn on poor land,” said Stephen Long, University of Illinois plant biology and Institute for Genomic Biology professor.

Long and his colleagues have calculated the total land areas needed to produce enough miscanthus to meet the renewable fuels standard (RFS) mandate for cellulosic ethanol in 2022. They determined it would take 17 million acres of miscanthus or 39 million acres of switchgrass. To put that in perspective, the continental U.S. is comprised of about 2 billion acres, with 20 percent of that used in row-crop agriculture.