At the turn of the last century, most of the nation's transportation and industries ran on power generated by plant biomass – the hay and feed that fueled more than 20 million horses and mules. As the century turns again, plant biomass is being touted as a potential major fuel source for the future.

A Nebraska native – switchgrass – has been selected as the U.S. Department of Energy's (DOE) top crop candidate for biomass fuel conversion. Thanks to the foresight and early research of Ken Vogel, a USDA-Agricultural Research Service geneticist in the University of Nebraska agronomy department, the university is a leader in developing this native prairie grass into a viable renewable fuel source.

"The idea is that using switchgrass as a renewable source of liquid fuel, in the form of ethanol, could boost our rural economy," Vogel said. "Switchgrass can be grown on marginal land, it's high yielding and it's environmentally friendly."

Ethanol for fuel now is produced mainly from corn starch, which is easily converted into glucose, the sugar fermented to produce ethanol. Switchgrass also contains abundant sugars but in the form of cellulose and hemicellulose – molecules much more difficult to break down into the simple sugars used in fermentation.

"The technology for converting biomass to ethanol is being developed," Vogel said. "The question is, how much do we want to pay for it?"

The DOE is confident this technology will be available and affordable by 2010, Vogel said. His job is to have the highest-yielding, best-performing switchgrass possible ready for large-scale production by then.

"Our goal is for the farmer to be able to get switchgrass established and have half of full production yields the first year, and then have full production in the second year," he said. "And we want to be able to produce 8 to 10 tons of biomass per acre in the 25-inch rainfall zone."

In 1990, Vogel notified officials at DOE's Oak Ridge National Laboratory of his extensive collection of Midwestern prairie switchgrass germplasm. The upshot was a three-year grant to evaluate his germplasm and existing switchgrass cultivars for yield potential and stability.

As interest in biomass fuels heated up, Vogel's initial study evolved into a comprehensive program to develop both improved switchgrass cultivars and management practices to maximize biomass production. Collaborative projects with Institute of Agriculture and Natural Resources Agronomists Don Lee, Bob Masters, Dan Walters and Lowell Moser include determining the feasibility of hybrid switchgrass cultivars, developing molecular markers for genetics studies, studying seed quality and optimum fertility requirements, and determining the best herbicides for switchgrass establishment.

Research shows that switchgrass production could work economically for farmers, Vogel said. His goal of 8 tons of biomass per acre is reachable – early trials yielded 6 tons per acre in a single cut; hybrid cultivars have the potential to increase yields by 30 percent. The ability of switchgrass to produce these high yields on marginal land is the key.

"Right now there are 40 million acres in CRP (Conservation Reserve Program) that could be used for biomass production, without displacing corn or other crops," Vogel said.

A detailed USDA study predicts that introducing switchgrass as a bioenergy crop on 42 million acres at a price of $40 per dry ton could boost U.S. net farm income by $2.3 billion to $5.5 billion annually – and increase Nebraska's net return by $83 million. Bioenergy crops could give farmers a reliable income buffer from grain price swings.

A new five-year, on-farm trial project in Nebraska and the Dakotas will add real-life data to the economic models, Vogel said. It will gather field-scale yield and production information and track the farmer's economic costs. The U.S. Department of Energy and the USDA-ARS fund this research.

–Monica Norby

Ken Vogel, a USDA-Agricultural Research Service geneticist at NU, walks through a field of young switchgrass. He's developing improved switchgrass cultivars for biomass fuel production.

Research Technician Steve Masterson weighs switchgrass seed in the lab.

A mature switchgrass plant. Below far right: Switchgrass grows beside young corn in a test plot. Farmers someday might raise switchgrass as a biomass fuel crop.