Opuntia humifusa
Med. Fl. 2: 247. 1830.
Shrubs, forming clumps or often prostrate, usually only 1 or 2 stem segments tall, to 0.5 m (except in Florida where they may be erect and reach to 2+ m with short trunk), flattened to obovoid, sometimes from tuberlike rootstocks. Stem segments not disarticulating, dark or bright shiny green, wrinkling when stressed, circular to broadly oblong to obovate, 5–17.5 × 4–12 cm, fleshy, usually tuberculate, glabrous; areoles 4–6 per diagonal row across midstem segment, oval to circular, 2–4 mm diam., not raised, sometimes somewhat sunken; wool tan to brown. Spines often absent or 1–2(–3) per areole, spreading, whitish to brownish, terete, straight, and usually stout, 25–60 mm; occasionally also 1 deflexed spine present. Glochids in dense crescent of adaxial edge of areole and in dense tuft overtopping crescent in age, yellow to red-brown, to 4 mm. Flowers: inner tepals pale to bright yellow throughout, 20–30 mm diam.; filaments yellow to orange; anthers pale yellow to cream; style and stigma lobes white. Fruits greenish, tardily becoming apricot to brownish red, elongate, 30–50 × 12–20 mm, fleshy, tapering at base; pulp green and sour, becoming reddish and sweet under ideal conditions; areoles 10–18. Seeds tan, 3.5–4.5 mm diam., thickish; girdle protruding to 1 mm.
Distribution
Ont., Ala., Ark., Conn., Del., Fla., Ga., Ill., Ind., Iowa, Kans., Ky., La., Mass., Md., Mich., Minn., Miss., Mo., N.C., N.J., N.Y., Nebr., Ohio, Okla., Pa., R.I., S.C., S.Dak., Tenn., Tex., Va., W.Va., Wis.
Discussion
Varieties 2 (2 in the flora).
Selected References
None.
Key
| 1 | Shrubs forming clumps, often prostrate, usually only 1 or 2 stem segments tall, to 0.5 m | Opuntia humifusa var. humifusa |
| 1 | Shrubs or small trees, erect, to 2 m | Opuntia humifusa var. ammophilia |