Habit: Perennial herb or shrub, erect to decumbent, many-branched, matted, succulent.
Stem: winter- or drought-deciduous, regularly segmented, segments < 30 cm, < 6 cm diam, cylindric to club-shaped, fleshy, glabrous; ribs 0, tubercles generally elongate, occasionally 0.
Leaf: deciduous.
Spines: 0--many per areole, densest and longest near stem tip, < 4 mm wide, awl- to dagger-shaped, flat to angular, straight, roughened, tip smooth or barbed, epidermis at spine tip separating as a papery sheath; glochids generally numerous in each areole.
Flower: lateral to terminal on stem, from upper portion of areole, 30--50 mm diam; perianth yellow or pink; ovary glabrous, spines 0--many, glochids many in each areole, scales 0.
Fruit: indehiscent, obconic, base generally long-tapering, glabrous to densely spiny, glochids many in each areole.
Seed: 3--6 mm, +- round, encased in an aril; bony, +- white when dry.
Species In Genus: 14 species: North America, Mexico.
Etymology: (Hermann August Jacques Gruson, German engineer, industrialist, 1821--1895)
Note: Hybridization unknown.
Jepson eFlora Author: Marc Baker, Bruce D. Parfitt & Jon Rebman
Index of California Plant Names (ICPN; linked via the Jepson Online Interchange)Key to Grusonia
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