by LYLE GLASS.
Huge snowball made by Mother Nature. When the snow drifts, it often forms an overhang at the edge of the buttes. Then on a warm day, or when the snow is wet and heavy, a portion of the overhang drops off and rolls down the hillside, gathering more snow and forming the naturally made snowballs.
Adjusted in PSE7. Photographed in Theodore Roosevelt National Park, South Unit, Medora, North Dakota on 3-31-2009 at 6:40 p.m.