Sp. Pl. 2: 1030. 1753.
Vines. Stems annual, climbing, branching, to 2.5 m, herbaceous, glabrous; prickles absent. Leaves: petiole thin, 1–6 cm; tendrils numerous, long, functional; blade oblong-ovate, ovate, or round, 4.5–12 × 3–9 cm, glabrous abaxially, base cordate to truncate, margins entire, apex obtuse to acute; proximal cauline leaves narrower and smaller. Umbels many, axillary to leaves, 20–100+-flowered, globose; peduncle to 30 cm, progressively shorter distally. Flowers: perianth greenish, carrion-scented; tepals 3.5–4.5 mm; anthers much shorter than filaments; ovules (1–)2 per locule; pedicel 0.5–2 cm. Berries blue, subglobose, ca. 10 mm diam., glaucous. 2n = 26.
Phenology: Flowering May–Jun.
Habitat: Higher elevations in rich woods, alluvial thickets, and meadows, often in calcareous soils
Elevation: 100–800 m
N.B., Ont., Que., Ala., Ga., Ky., Maine, Md., Mass., N.H., N.Y., N.C., Ohio, Pa., S.C., Tenn., Vt., Va., W.Va.
The leaves and habit of Smilax herbacea are quite variable.