It's not quite as easy as collecting lawn clippings and yard waste and converting and distilling them in the garage into ethanol to run the family sedan - but it's close.

While professor Stephen J. Herbert of the Plant, Soil and Insect Sciences Department at the University of Massachusetts is comparing different varieties of a once-abundant prairie grass as a source of biomass for conversion to ethanol, professor Susan B. Leschine, senior faculty member and microbiologist, is working with a microbe, called simply the Q microbe and found in soil near Quabbin Reservoir, to make that conversion a one-step process.

Switch grass is a tall, somewhat rigid grass that once thrived on the Great Plains, while crambe is an oil-seed crop.

At the UMass Research Farm in South Deerfield and eight other test farms from Belchertown to Pittsfield, an evaluation of switch grass varieties is under way.

From another tangent, Ms. Leschine, chief scientist and a founding member of SunEthanol Inc. of Hadley, is working to determine if the Q microbe that has showed promise in lab tests has the same potential when ramped up for commercial ethanol production.

She said it's possible that "relatives" of the Q microbe could be found in environments similar to Quabbin - wet forest soils around the globe - but at this point, no one has looked at its distribution in the environment.

"The one most promising thing about the Q microbe is that it doesn't seem to have a preference. With some pretreatment, it will convert just about any biomass it encounters into ethanol," Ms. Leschine said.

The study of cellulose-based biofuel gained steam with the increasing number of voices questioning the use of corn, a food staple for both humans and livestock, as a source of fuel.

Mr. Herbert said the crop trial project was launched in 2006 and will continue for the foreseeable future based on total grants of $125,000 from the state Department of Energy Resources, the Department of Agricultural Resources, the Massachusetts Technology Collaborative and the university. The current grant money runs through 2009.

At the experimental farm and research station in South Deerfield just west of the Connecticut River, plots of different varieties of switch grass are being grown and evaluated for their economic potential.

Mr. Herbert said he and UMass Extension weed specialist Randall G. Prostak went to Nebraska last year.

"What we found out is that we needed 125,000 acres of switch grass within a 25-mile radius for a cost-effective supply of biomass for an ethanol production plant," Mr. Herbert said.

"Some day, perhaps we'll have the technology to make ethanol production viable at the community level," he said, adding until then switch grass could be formed into pellets and used for heating greenhouses and homes.

Mr. Herbert said baled switch grass could be used in wood-burning furnaces, or as a source of fuel in a power plant.

"We're seeing technology being developed on many fronts to make the most of this crop and the good news for farmers is that it can be grown successfully on marginal agricultural land. Because it's a perennial, it's harvested once a year, unlike a hay crop that is harvested three times a year, using that much more energy," he said.

The UMass research team is growing a dozen different varieties of switch grass, replicated three times with different soil and growing conditions.

Each of the plots occupies 200 square feet.

Based on preliminary research, Mr. Herbert said the recommended varieties are Blackwell, Carthage, Cave-in-Rock, Shawnee, Shelter, and Sunburst. The Alamo variety grew well the first year, he said, but originating in Texas, most plants did not survive subsequent winters.

"It's pretty much the result of genetics, and quite obvious from field trials, which varieties cope best with a New England winter," Mr. Prostak said.

Pointing to one of the test plots, Mr. Herbert said, "Take Dacotah for example. Just because it's from the north doesn't mean its going to be a better variety. This one is quite short. It matured more quickly, and is quite open. This particular variety might make excellent bird habitat, but it's not necessarily what we're looking for in maximum yield of biomass per acre."

He said one of the byproducts of the switch grass biofuel research is the identification of varieties that might be of interest to Massachusetts Audubon and other environmental groups as bird habitat.

Of immediate concern, however, is identifying the variety that delivers an annual yield of five to six tons of biomass for use as fuel.

Mr. Prostak said switch grass has demonstrated characteristics making it an optimum choice as a biofuel crop.

"It's got a life span as a perennial of 10 to 15 years; requires little or no work on the part of the farmer; and will grow on rocky or sandy soil that's not suitable for vegetable crops," he said.

"The only reason a farmer might make a change after 10 years, and plant a new crop of switch grass, is because an even better variety has come along. That's one facet of what we're doing right now - looking for the variety that produces the greatest amount of biomass per acre consistently under different soil conditions," Mr. Prostak said.

The weed specialist said phragmites - an invasive that grows in dense colonies and is crowding out native species in wetlands - has all of the characteristics one might like to find in a cellulosic biofuel. But the state's wetlands protection act would make harvesting this fast-growing and rapidly spread invasive plant species commercially impossible.

"Because its primary habitat is wetlands, and wetlands cannot be disturbed, phragmites is essentially getting a free pass; harvesting the crop would be expensive to say the least, to say nothing of the environmental damage that might occur, unless you were using something like a Hovercraft," he said.

Mr. Herbert and Mr. Prostak said what makes switch grass so attractive is that it's one crop where costs can be minimized at each step in the growing and harvesting cycle with the potential for a steady revenue given the demand for development of alternatives to fossil fuels and foreign oil.

Mr. Herbert said whether switch grass supplants corn as the primary crop for conversion to ethanol remains to be seen.

"To make this work, we truly need to commit switch grass to marginal agricultural land so that it's not taking land that otherwise would be used to grow vegetable crops," he said.

He said the success of switch grass as a source of ethanol may well depend on how well the Q microbe works at a commercial production level.