That's in addition to the 5 million acres of farmland that had been aside for conservation — more than Yellowstone, Everglades and Yosemite National Parks combined — that have vanished since Obama took office.
In South Dakota, more than 370,000 acres of grassland have been uprooted and farmed from since 2006. In Edmunds County, a rural community about two hours north of the capital, Pierre, at least 42,000 acres of grassland have become cropland — one of the largest turnovers in the region.
Malsam runs a 13-square-mile family farm there. He grows corn, soybeans and wheat, then rents out his grassland for grazing. Each year, the family converts another 160 acres from grass to cropland.
Chemicals kill the grass. Machines remove the rocks. Then tractors plow it three times to break up the sod and prepare it for planting.
Scattered among fields of 7-foot tall corn and thigh-high soybeans, some stretches of grassland still exist. Cattle munch on some grass. And "prairie potholes" — natural ponds ranging from small pools to larger lakes — support a smattering of ducks, geese, pelicans and herons.
Yet within a mile of Malsam's farm, federal satellite data show, more than 300 acres of grassland have been converted to soybeans and corn since 2006.
Nebraska has lost at least 830,000 acres of grassland, a total larger than New York City, Los Angeles and Dallas combined.
"It's great to see farmers making money. It hasn't always been that way," said Craig Cox of the Environmental Working Group. He advocates for clean energy but opposes the ethanol mandate. "If we're going to push the land this hard, we really need to intensify conservation in lockstep with production, and that's just not happening," he said.
Jeff Lautt, CEO of Poet, which operates ethanol refineries across the country, including in South Dakota, said it's up to farmers how to use their land.