SOPERTON, Ga. -- A farmer whose cotton fields had been ravaged by boll weevils put this town on the map in the 1920s by plowing under his crop and replacing it with hearty pine trees.

James Fowler's enterprise eventually expanded to 7 million trees on 10,000 acres, spurred a national Depression-era reforestation movement, pioneered the use of Southern pine in paper manufacturing -- and gave tiny Soperton its nickname, "Million Pines City."

Does alfalfa -- the nation's most planted legume and its third most valuable crop -- have a future in a growing U.S. effort to produce its own energy supply?

Some Agriculture Department scientists think so.

"We see alfalfa as a crucial crop for the biomass feedstock portfolio," said Michael Russelle, a USDA soil scientist.

There's good reason to root for alfalfa to become a key ingredient in cellulosic ethanol, Russelle and other scientists say. It is plentiful -- already planted on millions of acres for livestock feed -- and it is good for the environment.

GETTYSBURG, Pa. -- Richard Waybright's cows produce 6,000 gallons of milk a day -- and generate enough electricity to run his sprawling dairy farm and earn a monthly check from the power company.

Waybright's 2,400 milk cows have been supplying the juice at Mason-Dixon Farms since 1979. Spurred by that decade's energy crisis -- marked by long lines at gasoline stations, fears of petroleum rationing and 40 percent price hikes at the gas pump -- the far-sighted farmer invested in equipment to tap methane from cow manure.

And now, with energy prices soaring, milk prices in flux and environmental regulations for farm wastes on the rise, many farmers are doing what Waybright did almost three decades ago: installing anaerobic digesters.