The nearby depression survives from an epoch when great buffalo herds migrated through west Texas, many moving between present Canada and Mexico over two major trails in the Odessa area. Wallows began with individual buffalo rolling in the dirt to rid themselves of pests or shed their heavy winter coats in springtime. Repeated wallowing in the same spot by countless buffalo created an efficient depression to accomplish the cleaning ritual. Most wallows were eight to 12 feet across and two feet deep. Buffalo existed in the millions in north America, ranging throughout the western and central plains of Texas. They were pursued seasonally by the plains Indians, who subsisted on the food and clothing the buffalo provided. In the late 19th century, railroads bisected their trails, isolating the herds and providing transportation of meat and hides to distant markets. In Texas vast buffalo slaughters were encouraged in the 1870s by the army, who wanted to deprive Indians of their commissary; settlers, who had crops trampled and forage consumed by the passing herds; and hunters, who realized quick profit particularly from hides. The buffalo had all but disappeared from this area when Odessa was founded in 1886. (1986)