When President Barack Obama gave a major policy speech on reducing greenhouse gases last June, he didn't once mention ethanol, an alcohol-based fuel distilled from fermented corn. Biofuels in general — which are extracted from plant or animal matter — received a brief, passing reference.

But when the Iowa political caucuses were on the horizon in 2007, then–presidential candidate Obama made homegrown corn a centerpiece of his plan to slow global warming. And when former President George W. Bush signed a law that year requiring oil companies to add billions of gallons of ethanol to their gasoline each year, Bush predicted it would make the country "stronger, cleaner and more secure."

But the ethanol era has proved far more damaging to the environment than politicians said and much worse than the government admits today, an Associated Press investigation found. As farmers rushed to find new places to plant corn, they wiped out millions of acres of conserved land, destroyed habitats and polluted water supplies.



Five million acres of land — more than in Yellowstone, Everglades and Yosemite national parks combined — have been pulled from conservation on Obama's watch, according to Agriculture Department figures.

What's more, from 2005 to 2010, corn farmers increased their use of nitrogen fertilizer by more than 1 billion pounds. More recent data isn't available from the Agriculture Department, but because of the huge increase in corn planting, even conservative projections by the AP suggest another billion-pound fertilizer increase on corn farms since then.

Some of that fertilizer has seeped into drinking water, contaminating rivers and boosting the growth of enormous algae fields in the Gulf of Mexico; the algae eventually decompose, sucking oxygen from the water and leaving behind a huge dead zone, currently covering 5,800 square miles of sea floor where marine life can't survive.

That dead zone is just one example of a peculiar ethanol side effect: As one government program encourages farmers to plant more corn, other programs pay millions to clean up the mess.

Farmers planted 15 million more acres of corn last year than before the ethanol boom, and the effects are visible in places like south-central Iowa.

The hilly, once grassy landscape has a fragile soil that, unlike in the rest of the state, is poorly suited for corn. Nevertheless, it has yielded to America's demand for it.

"They're raping the land," said Bill Alley, a member of the board of supervisors in Wayne County, which now bears little resemblance to the rolling cow pastures shown in postcards sold at a Corydon pharmacy.