Yesterday, Dan Morgan wrote in the Washington Post about the continued clearing of precious wildlife habitat and ecologically critical lands to make way for growing crops for ethanol production.

Today, signs of change are clearly visible. Emerald fields of ripening crops stand out against a sea of tawny grass in which a single square yard can hold 100 plant species.

This could easily have come from the thousands of stories documenting the deforestation of Brazilian rain forests. Instead, Mr. Morgan's piece centers on the prairie pothole region of North America.

The ducks arrive in early April, zeroing in on thousands of shallow ponds fed by melting snow amid a vast prairie. As the pintails, mallards and blue-winged teal make nests in the grass and feed their young on abundant aquatic insects and freshwater shrimp, a 276,000-square-mile area reaching across five states and into Canada is transformed into one of the world's greatest habitats for migrating birds.

Now this swath, known as the Prairie Pothole Region because of the depressions formed long ago by retreating glaciers, is threatened by the steady advance of farming. Spurred by federal subsidies and two years of surging commodity prices, farmers increasingly are digging up the grass to plant crops, raising concerns among cattle ranchers, hunters and environmental groups about the future of land where Sioux hunters chased grazing buffalo a mere century and a half ago.

The late conservationist Tony Dean was an ardent advocate for this region, one of the reasons he partnered with EWG to fight against proposed conservation cuts. Mr. Morgan also highlights one of the major culprits of this continued decimation of the prairie pothole region -- the subsidies and ethanol production mandates put in place that have accelerated unprecedented corn and soybean planting.

Consider this about our irrational ethanol policy of mandates and subsidies. The federal government is using three out of every four tax dollars spent on renewable energy on corn ethanol -- that includes wind, solar, and geothermal.

Yet if the entire US corn crop was converted into ethanol, we would displace only 15 percent of the gasoline we use each year. Furthermore, according to the Iowa Department of Natural Resources, the emissions from ethanol plants in Iowa alone equal the emissions from 1.4 million cars. That's on top of the increased run-off exacerbating the Gulf "Dead Zone" and the aforementioned destruction of wildlife habitat.

Meanwhile, proven conservation programs that could help mitigate the havoc the rush to corn is causing on our land, are woefully underfunded. And if you're looking for funds to help conservation, forget the five billion dollar per year in automatic fixed "direct payments" that go out to big farm operations, many of them growing corn, whether they need it or not.

Prairie grasslands

A corn field

Brazilian rainforest

Brazilian sugarcane