EDIT: I forwarded this pic to a meteorologist at one of my local TV stations. This is what he had to say about it:
Photo looks like a hoax to me, photoshopped. Not the storm itself, but that is not what the storm that hit the camp ground would have looked like. That photo is of a classic supercell whereas the storm that hit Iowa was HP (high precipitation), the tornado would have been wrapped in rain and much more difficult to see than the highly contrasted wall cloud you see in this photo (that's not even a tornado hanging below the cloud base). Just an FYI, thanks for sharing though!
2nd Edit: Okay, so apparently it isn't a Photoshopped pic, but it's not the one that hit the Boy Scout camp in Little Sioux, IA. This one touched-down in Orchard, IA.