Farmers place cattle feed in round metal fences that the cows can eat out of. The cattle scar the earth around the feed enclosures. The farmers move the enclosures around (I'm guessing to spread the manure and reduce the scarring in one place.)
Also, on the southwest side of the farm house there are some more shapes that don't all appear to be circles, and they seem to be in a plowed field. There is also what looks like a dark foggy cloud on the south side of the house as well. It's just weird.
Anonymous was me, btw.
Anonymous
@ 2005-07-11 02:05:25
I think that they might be something like prairie dog mounds or something like that. That guy might have a prairie dog town in his back yard.
Farms - Irrigation Circles 
But still why are there different sizes?
Anonymous was me, btw.
http://maps.google.com/maps?ll=38.209430,-97.893687&spn=0.004994,0.007308&t=k&hl=en