Fl. Amer. Sept. 1: 113. 1814.
Herbs, annual, with taproot, 1.5-8 dm. Stems usually branched from base, erect or reclining. Leaf blades narrowly ovate to orbiculate, distal blades sometimes lanceolate, 2-8 × 1-6 cm, base nearly cordate to rounded, sometimes cuneate in distal leaves, margins serrate, apex rounded to acute; cystoliths rounded or ± elongate. Inflorescences ± globose cymes. Flowers unisexual, staminate and pistillate intermixed in same inflorescence, sessile to short-pedunculate. Pistillate flowers: outer tepals linear, 0.4-0.8 mm, inner tepals ovate, 1.4-2 × 1-1.4 mm. Achenes ovoid to broadly ellipsoid, 1.2-1.4(-1.6) × 0.8-1 mm. 2n = 26.
Phenology: Flowering all year except early winter.
Habitat: Rich, wooded slopes, bluffs, stream banks, swamps, waste places, and fields, often on limestone or nearly neutral soils
Elevation: 0-600 m
Ala., Ark., Fla., Ga., Ill., Kans., Ky., La., Miss., Mo., N.C., Ohio, Okla., S.C., Tenn., Tex., n Mexico.