He proves us wrong.
White House spokespam Trent Duffy blamed Bush's bicycle accident on the weather, saying "It's been raining a lot and the topsoil is loose."
Except, of course, that it hasn't rained in Crawford for over a week.
In other news, George W. Bush has announced the War on Topsoil. He plans on aggressively attacking the problem with the help of several major U.S. corporations, who will stripmine, pollute, irradiate, and salt all remaining arable land.
A spokesman for the Bush campaign proudly proclaimed "This is one war in which we're already well on our way to victory!"