And much better renewable fuels then Ethanol.
If a farmer is looking to maximize his subsidy income, growing corn for Ethanol is a good idea for him. If he is looking to maximize his BTU production, growing rapeseed (or another oil crop) for BioDiesel is a much better idea.
Farmers pay the bills with dollars, not BTUs, so they grow corn for Ethanol.
It has nothing to do with these subsidies that everyone seems to conjur up, but with yield and value. An acre of midwestern land will produce , what, five times as much corn as canola?