The desert form attains a much larger size than the coastal species. Common in the lower elevations of the Mojave and Colorado Deserts, the barrel cactus is usually found on rocky or gravelly hillsides and alluvial fans. It usually attains a height of 3 to 4 feet and a diameter of about one foot. Ribs run the length of the body. The spines may reach a length of 6 inches. Yellow flowers are produced at the top of the cactus in the spring. Indians used to hollow out the barrel cactus and use it as a cooking pot.