WASHINGTON – Negotiators finalizing sweeping new changes in U.S. farm and nutrition programs could decide the contours of Minnesota's shrinking native prairie.

Among the sticking points in the farm bill talks, long stalled on crop subsidies and food stamps, are provisions protecting grasslands that naturalists say are being depleted at a rate not seen since the Dust Bowl days.

Although the losses have been greater in other Midwestern states such as Nebraska, Iowa and South Dakota, a pair of Minnesota Democrats have taken the lead in pressing for compliance measures and "sodsaver" protections meant to stem the conversion of wetlands and grasslands to agriculture.

But the conservation provisions backed by Sen. Amy Klobuchar and Rep. Tim Walz are so far part of only the Senate version of the farm bill. Decades-old requirements linking certain conservation practices to farm subsidies have been dropped in the bill passed by the Republican-led House, alarming environmentalists who have tracked the loss of prairie during a period of strong commodity prices.

"Once we lose the connection to the direct payments which are the primary farm program that gives us the most bang for our buck, conservation compliance literally goes by the wayside," said Bill Wenzel, agriculture program director for the Izaak Walton League of America.

Minnesota farmers, who grow crops under land conservation programs dating back to 1985, say they have no problem with maintaining practices designed to preserve native grasses and protect highly erodible land.

"The vast majority of farmers are in compliance," said Northfield corn and soybean producer Bruce Peterson, of the Minnesota Corn Growers Association. "We don't want to see environmental degradation, either."

However, with farm aid shifting from a system of direct payments to crop insurance subsidies, some farm groups say federally mandated conservation compliance might keep farmers from signing up for coverage and may no longer be necessary.

'Redundant'

House Agriculture Committee Chairman Frank Lucas, R-Okla., issued a statement in the lead-up to the final 2013 farm bill negotiations, calling the compliance measures "a redundant regulatory burden on people who are already the best caretakers of our natural resources and who already have conservation practices in place."

Some negotiators on the farm bill's secretive House-Senate conference committee have proposed a more limited program restricted to parts of Minnesota, Iowa, Montana and the Dakotas.

But Walz, one of the House negotiators, is pushing for a nationwide sodsaver program that would serve as a broad disincentive to plow up grasslands. He remains "cautiously optimistic" that it will be included in the final farm bill, spokesman Tony Ufkin said.

Walz and Klobuchar cite a Congressional Budget Office study projecting that the grasslands measure would protect wildlife habitat and save taxpayers $200 million over 10 years in the insurance program.

"Outdoor recreation and agriculture are both vital to Minnesota's economy, and we need to make sure that we have policies in place to protect our state's natural resources," Klobuchar said.

'Just not there'

Klobuchar, working with John Thune, R-S.D., co-sponsored a provision in the Senate version of the farm bill that would reduce insurance subsidies for crops grown on native sod converted to cropland, as well as on land that a producer cannot verify has ever been tilled. The provision is supported by farm and conservation groups, including the National Farmers Union, Pheasants Forever, Ducks Unlimited and the National Wildlife Federation.

The farm bill debate follows recent government reports documenting the rapid conversion of land to crops across the Midwest, notably in Nebraska, Texas and South Dakota. Minnesota ranked 10th in a U.S. Agriculture Department survey last year, with 12,453 additional acres turned over the crops. That's an area larger than the city of Edina.

A National Academy of Sciences study found that from 2006 to 2011, 1.3 million acres of grassland and wetland were converted to crops in the Dakotas, Nebraska and parts of Minnesota and Iowa — a conversion rate that the National Wildlife Federation compared to the Dust Bowl era.

Environmentalists say that taxpayer-supported crop insurance has contributed to that decline. Farm groups maintain that the conversion rates are a reflection of acreage set aside during hard years of low commodity prices.

The majority of corn acres added in Minnesota in recent years have come not from virgin land, Peterson said, but from acres that were used for pasture or for other crops such as wheat.

"Where are you going to find these grasslands to plow up?" he said. "They're just not there."

What is clear is that there is little virgin land to convert to cropland in Minnesota. By some estimates, as little as 1 percent remains of the vast native prairie that once stretched across the state.

The state and a consortium of conservation groups have launched a 25-year plan to preserve the vanishing prairie, to offset the land pressures of development and farming.

Farmers are critical in that effort, Wenzel said, but they need help from Congress. "We have nothing against farmers trying to maximize their bottom lines," he said. "The problem is in the policy."

Kevin Diaz • 202-383-6120