Woolly Cactus

(Engelmann & J. M. Bigelow) Britton & Rose, Smithsonian Miscellaneous Collections 50: 535, 1908 Lectotype (O. missouriensis trichophora); Herbarium; Herbarium; Herbarium; Herbarium; Herbarium; Herbarium; Drawing (The Botany of the Expedition, 1856, plate XV No. 1-4 [O. missouriensis trichophora]) Opuntia trichophora is possibly related to O. arenaria O. trichophora is related to O. diploursina O. trichophora is related to O. polyacantha Original Citation What is