About 700 pounds. Compared to beavers, groundhogs/woodchucks are not adept at moving timber, although some will chew wood. (At Cornell, woodchucks that gnaw their wooden nest boxes are given scraps of 2-by-4 lumber.) A wildlife biologist once measured the inside volume of a typical woodchuck burrow and estimated that -- if wood filled the hole instead of dirt -- the industrious animal would have chucked about 700 pounds' worth.
Sources: College of Veterinary Medicine, Cornell University; New York State Department of Environmental Conservation; Mammals of the Eastern United States, Second Edi tion, William J. Hamilton Jr. and John O. Whitaker Jr.
at 11:39 AM on Sep. 18, 2010