Trees or shrubs, spreading, densely branched, 0.5-2 m. Stem segments usually firmly attached, terminal segments sometimes easily detached, green to light gray-green, cylindric, 3-7.5(-12) × 1-2.5 cm; tubercles salient, short oval, 0.4-1.3(-1.5) cm, moderately broad; areoles broadly elliptic, 4-4.5 × 2-3.5 mm; wool whitish, yellow to tan, aging gray. Spines (6-)10-17(-22) per areole, accompanied by 0-5 short bristlelike spines at areole margins, at most areoles, most prominent in adaxial ones, much interlaced with those of adjacent areoles, obscuring stems, sometimes brushlike; major abaxial spines whitish, yellow to tan, usually subterete to flattened, spreading to deflexed, the longest 20-30(-45) mm; major adaxial spines erect or spreading, white, pale yellow, or tan to brown (rarely deep red-brown), terete, the longest 22-35(-50) mm; sheaths whitish with yellow to golden tips, baggy. Glochids conspicuous in broad adaxial crescent, yellow, 3-4(-5) mm. Flowers: inner tepals light green to yellow-green, sometimes suffused with maroon or rose, spatulate, 20-23 mm, emarginate-apiculate; filaments greenish white or yellow, sometimes suffused with bronze or rose, but not red; anthers yellow; style and stigma lobes whitish, cream to light green. Fruits tan at maturity, obconic to subspheric, 13-23 × 11-20 mm, dry, tuberculate, densely spiny, sometimes burlike, with apical flange around deep umbilicus; basal tubercles not markedly longer than distal ones; areoles 16-24(-36). Seeds pale yellow, angular to squarish in outline, warped, 4-6 × 3.5-5 mm, sides smooth, each with 2-4 large depressions; girdle smooth (rarely with very narrow ridge). 2n = 22.
Mojave and Sonoran deserts, desert grasslands, juniper and oak-juniper woodlands, flats, bajadas, canyons, sandy, loam, alluvial to gravelly substrates; at elevations from 50-1,700 metres.
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