19. Smilax tamnoides Linnaeus, Sp. Pl. 2: 1030. 1753.
China root, hellfetter, bristly greenbrier
Smilax grandifolia Buckley; S. hispida Muhlenberg ex Torrey; S. hispida var. australis Small; S. hispida var. montana Coker; S. tamnoides var. hispida (Muhlenberg ex Torrey) Fernald
Vines; rhizomes knotty, short. Stems perennial, climbing, branching, terete, to 7+ m × 9 mm, woody, glabrous, with prickles proximally, prickles usually absent distally; prickles blackish, unequal, 3–10+ mm, bristly, flexible. Leaves ± persistent in southern part of range, deciduous in north; petiole 1–2 cm; blade green, drying to light olive-gray, ovate-lanceolate, ovate, or sometimes pandurate, prominently reticulate, thin, 5–13 × 3–10 cm, not glaucous, glabrous (to prickly on major veins abaxially), base rounded to cordate, margins entire apically, minutely serrulate basally, thin, flat, not banded, not lobed, apex pointed. Umbels many, axillary to leaves, to 25-flowered, open to dense, spherical; peduncle often drooping, 1.5–6.5 cm. Flowers: peri-anth green to bronze; tepals 4–5 mm; anthers ± equaling to shorter than filaments; ovule 1 per locule; pedicel 0.4–1.2 cm. Berries black, globose, 6–10 mm, not glaucous.
Flowering May--Jun. Wet to dry woods, thickets, bottomlands; 0--400 m; Ont.; Ala., Ark., Conn., Del., D.C., Fla., Ga., Ill., Ind., Iowa, Kans., Ky., La., Md., Mass., Mich., Minn., Miss., Mo., Nebr., N.J., N.Y., N.C., Ohio, Okla., Pa., S.C., S.Dak., Tenn., Tex., Vt., Va., W.Va., Wis.
Smilax tamnoides is marked by its dark, flexible, and unequal bristles and leaves with minutely serrulate margins basally. The far-western S. californica appears to be closely related but lacks the serrulate margins of the leaf bases.