Cylindropuntia imbricata var. imbricata
Trees, with short trunks, openly branched, 3(–5) m. Stem segments 12–40 cm; tubercles widely spaced. Spines and sheaths usually tan to dirty white or ± yello, sometimes absent. 2n = 22.
Phenology: Flowering spring–summer (May–Aug).
Habitat: Deserts, grasslands, pinyon-juniper woodlands, hills, plains
Elevation: (800-)1100-1800(-2200) m
Distribution
Ariz., Colo., Kans., N.Mex., Okla., Tex., Mexico (Chihuahua, Coahuila, Durango, Nuevo León, San Luis Potosí, Tamaulipas, Zacatecas).
Discussion
A dominant cholla of the Chihuahuan Desert, Cylindropuntia imbricata var. imbricata is wide- ranging and variable in several characters; it is generally shorter and more spiny northward (there often referred to as Opuntia arborescens). The species appears to be spreading northeastward in Oklahoma and Kansas as a result of cattle ranching activities. In Arizona, New Mexico, and Mexico, var. imbricata intergrades with C. spinosior. Northward, var. imbricata hybridizes with C. whipplei (= C. ×viridiflora).
Selected References
None.