Cows and ethanol

I've been reading a lot lately about the pending corn shortage. Corn has been used for centuries to feed both humans and livestock. But recently the demand for it has grown as a biofuel, using it to make the gasoline substitute E85 (an ethanol blend). George Bush's call to reduce the use of gasoline in the US just fueled (so to speak) the fervor over ethanol as a substitute, as will the report on global warming coming out this week.

But the supply of corn isn't unlimited. Peasants in Mexico are uprising over a sharp increase in the price of tortillas, a dietary staple, the result of a shortage of their primary ingredient: corn.

I doubt that anyone is going to suggest we curb the use of biofuels. Nor are we likely to give up corn (in all its forms, including the ubiquitous corn syrup) as people food. So what's the obvious change? Livestock.

Cattle didn't always eat grain. Their stomachs are made to digest grass, and some theorize that it's the bacteria spawned by their unnatural diets that both force farmers to feed them antibiotics and create the E.coli that can cause so much havoc in humans. Switching cattle to a grass diet - how many problems might that solve?