we have the same problem with a foodplot we are putting in this year.. lots of stumps. in 2 hours, we were only able to dig out, and chop all the roots and teh tap root of 3 stumps. However, unlike you, these are about 18-24 inch dia. stumps. I agree with bowmanaj when he says just get a bunch of buddies together and put in the hard work. For me, the more hard work i put in, the more i appreciate when I harvest a deer over the foodplots I planted becuase I think about all the hardwork I put in, in puttin in that foodplot..