Stems erect, branched, 3–15 dm, glabrous. Leaves nonaromatic; petiole 0.15–0.45 cm; blade ovate to triangular, 3.5–15 × 2–9 cm, base cordate to truncate, margins sinuate-dentate with 1–5 coarse, acute teeth, distal leaves entire or with few small teeth, apex acute, glabrous. Inflorescences glomerules in terminal and lateral spikes and panicles, 6–15 cm; glomerules irregularly globose, flowers in different stages of development, 0.5–2 mm diam.; bracts absent. Flowers: perianth segments 5, connate into 0.5 mm tube; lobes ovate to lanceolate, 0.7–1 × 0.4–0.6 mm, apex retuse, slightly keeled, glabrous, margins meeting or separated by as much as their width, exposing more than 1/2 fruit at maturity; stamens 5; stigmas 2, 0.1 mm. Achenes depressed-ovoid; pericarp adherent, chartaceous, smooth. Seeds lenticular, 1.3–1.9 mm diam.; seed coat black, indistinctly honeycombed to nearly smooth, margins rounded. 2n = 18.
