"The amount of corn consumed by the ethanol industry combined with continued demand from overseas has cattle and hog farmers worried that if corn production drops due to drought or another natural disaster, the cost of feed could skyrocket, leaving them little choice but to reduce the size of their herds. A smaller supply could, in turn, mean higher meat prices and less selection at the grocery store.
The ethanol industry argues such scenarios are unlikely, but farmers have the backing of food manufacturers, who also fear that a federal mandate to increase production of ethanol will protect that industry from any kind of rationing amid a corn shortage."
A goal of the industry has been to use biomass instead of actual grain. A plant in the UK will be built soon to use biomass as fuel. Research into this is ongoing, such as in Wisconsin. Biomass can be grown in soil and conditions not good for food crops as well. It's just that biomass is harder to "digest" in order to get energy out than corn or other grains. Research has been done on how animals process biomass to get energy.
Biomass is the way to go rather than using our food supply to make fuel.