The Cactus Family is found mostly in the New World, and while our parks have only 2 species, parks of the southwest may have dozens of species. The species illustrated here is frequently seen in the Mammoth area; O. fragilis is seen on gravelly terraces above the Snake River. The cacti can be recognized by thick, fleshy, green stems which are armed with spines. The conspicuous yellow flowers posses numerous sepals, petals and stamens. The Blackfeet Indians treated warts by lacerating them and applying the fuzz from the cactus. {Plants of Yellowstone and Grand Teton National Parks by Richard J. Shaw pg 90}