Rising wood pulp prices also are increasing the direct sale potential of hybrid poplar to paper mills. This may well have a greater short term impact than the biomass energy market in encouraging hybrid poplar production. A 1993 survey of CRP contract holders in 8 western Minnesota counties showed that 60 percent were interested in growing hybrid poplar. Corn The biomass market currently most developed is corn ethanol. Spurred by favorable gas tax credits, the U.S. industry has grown to about 1 billion gallons per year.
Corn ethanol is sold as a gasoline additive that reduces air pollution.
Corn usually is not an appropriate crop for marginal farmland. Alternatives to corn should be considered for highly erodible land. However, much of the CRP land in Minnesota can support corn without causing environmental damage if grown using conservation practices. New technologies show promise for making ethanol from cellulose-based crops such as grasses, trees, and corn plant residues. Other Crops Researchers are evaluating other potential energy crops, including biodiesel from soybean oil, industrial hemp, switchgrass, and crop residues.