Before the long-frozen winter sets in, buffalo grow thick coats to insulate their bodies against the extreme elements. Enormous herds traveled great distances from their summer grasslands to the lower, winter grazing grounds, and as spring arrived, the herds would travel along well used trails back to the plains of the summer grounds. As warm weather dawned, the shedding of winter coats began. Buffalo had places where they would wallow and roll in fine dirt to rid themselves of insects and loosen the molting hair. Large rough rocks protruding from the grasslands were used by these massive animals to scratch and rub against to help remove their winter coats. In this sculpture Bill is depicting an historic scene as one of the millions of buffalo migrating across the grassy plains. The “rubbing rocks” have been worn smooth over eons of time by the herds of buffalo which passed.