A team of research scientists from the University of Illinois (United States) report an "integrated biogeochemical and economic analysis of bioenergy crops in the Midwestern United States". One of the aims of the study was to determine the viability of "biofuel grasses" (miscanthus and switchgrass) as cash crops in the United States and how viability is affected by location. Using an integrated biophysical model of bioenergy crop yields with economic analysis, they examined how break-even prices differ across bioenergy crops and across different locations in the Midwestern United States. Among the results (as highlighted by Bioenergy site) are: (1) miscanthus generally showed a three-fold higher yield compared to switchgrass in the Midwest; (2) even if switchgrass is native to the region (Midwest), it has poor cold tolerance, and does not grow well in higher latitudes (i.e. Minnesota, Wisconsin); (3) biomass yields for both miscanthus and switchgrass were higher in the south than in the north; (4) the costs of cultivation were shown to vary between miscanthus and switchgrass, and farmers may have to consider tradeoffs in the choice of bioenergy crop; for example, miscanthus has a higher yield and longer lifespan, but it is planted from small sprouts (called "rhizomes"), which is more expensive than switchgrass seed. The full results of the study are published in the journal, Global Change Biology Bioenergy (URL above).