Prairie and other natural landscapes have been plowed up at an unprecedented rate across the nation's midsection since 2008, especially in the corn belt -- which includes Minnesota and the Dakotas -- according to an analysis released Monday by a leading conservation group.

Between 2008 and 2011, some 37,000 square miles of grasslands, wetlands and shrublands were transformed into cropland across the nation, said the study by the Environmental Working Group, which uses data analysis to try to influence public policy on public health and conservation issues.

In Minnesota, where half the total land mass is devoted to corn and soybeans, 2,000 square miles of native grassland and wetlands were converted to row crops, the study said. In the Dakotas, a major breeding ground for aquatic birds and grassland species, an area twice that size was plowed up for crops.

Ken Cook, president of Environmental Working Group, said that the land conversion has been propelled by record high commodity prices, demand for ethanol, and by crop insurance programs that guarantee profits for farmers, even on marginal land.

That means less habitat for wildlife and more water pollution from agricultural runoff, he said.

"Land is being plowed up that hasn't been plowed up for a generation," he said during a briefing on Monday. "Farmers are planting in ditch rows and planting up against river banks and the damage is severe."

Eyes on new farm bill

The situation will accelerate if a House version of the new farm bill is approved. It does not require farmers to follow good conservation practices on their land in order to obtain taxpayer-subsidized crop insurance (the Senate version does).

Congress could take up the bill as early as September.

"There is a very, very strong correlation between those parts of the country where we are seeing the greatest loss of habitat, and those parts of the country where the government is providing the greatest amount of insurance subsidies to farmers," said Scott Faber, the group's vice president of government affairs.

Farm commodity and crop insurance groups did not respond to requests for comment on Monday, but they have urged Congress to sever the link between subsidy programs and farmers' choices about land management. In Minnesota, farm groups say that agricultural conservation practices have improved dramatically in recent decades, and that farmers have the greatest incentive of all to be good stewards of the land.

Crop insurance subsidies in the next federal farm law are expected to replace price subsidies and other programs protecting farmers from severe financial risk.

Crop insurance initially was designed to cushion farmers from the multitude of risks that come with making a living off the land, primarily weather. But now, about 80 percent of the nation's crop insurance policies are revenue policies, protecting farmers from weather, drops in prices and yield losses.

It shifts the risk of losses from farmers to taxpayers and insurance companies. Farmers paid $4.2 billion in premiums last year, while taxpayers shelled out $7.4 billion, including at least $94 million for Minnesota farmers.

'Good farmers ... bad rules'

Critics say the safety net gives farmers an incentive to farm where they shouldn't -- where it is too dry, too near water or too likely to erode -- because they are protected from revenue losses.

"A lot of good farmers are playing by bad rules," said Cook.

"It's a problem for fish and wildlife, but also for consumers who are paying to have their water treated before they can drink it."

It also means that many declining species, such as the prairie chicken and swift fox, have less critical habitat, increasing the chances that they will end up on the endangered species list, said the Defenders of Wildlife, which co-authored the report.

Faber said that while the trend was apparent from California to New York, the greatest concentration was in the Great Plains, where the corn belt is moving north and west. It includes huge swaths of land in such drought-stricken central states as Texas, Oklahoma and Nebraska.

The data for the report came from the federal Department of Agriculture, which collects satellite data about land use across the country.

Analysts did not have comparisons prior to 2008. But in the 20 years before 2008, the amount of cropland remained fairly stable, said Faber.

Josephine Marcotty • 612-673-7394


Farmers have converted more than 23 million acres of prairie, grassland and shrubland into land for crops since 2008, a new study says. Nearly three-fourths of the land is in 11 states, including Minnesota. They are:

Texas 3.08 million acres

South Dakota 1.94 million

Iowa 1.51 million

Nebraska 1.50 million

Oklahoma 1.45 million

Illinois 1.40 million

Minnesota 1.34 million

North Dakota 1.31 million

Missouri 1.27 million

Kansas 1.20 million

Wisconsin 1.14 million

Source: "Plowed Under," study by the Environmental Working Group and Defenders of Wildlife.

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