The Boston Globe reports on the loss of prairie lands to new corn production–not for food but to run our cars.

ROSCOE, S.D. — Robert Malsam nearly went broke in the 1980s when corn was cheap. So now that prices are high and he can finally make a profit, he’s not about to apologize for ripping up prairieland to plant corn.

Across the Dakotas and Nebraska, more than 1 million acres of the Great Plains are giving way to corn fields as farmers transform the wild expanse that once served as the backdrop for American pioneers.

This expansion of the Corn Belt is fueled in part by America’s green energy policy, which requires oil companies to blend billions of gallons of corn ethanol into their gasoline. In 2010, fuel became the number one use for corn in America, a title it held in 2011 and 2012 and narrowly lost this year. That helps keep prices high.

‘‘It’s not hard to do the math there as to what’s profitable to have,’’ Malsam said. ‘‘I think an ethanol plant is a farmer’s friend.’’