Description

Key Characters:

Growth Form: Erect herbs 4–9(–15) dm tall.

Stems: Stems usually branched, conspicuously striate, pubescent, especially above, the hairs multicellular.

Roots:

Leaves: Leaves simple. Alternate. Blades ovate to rhombic–ovate, blades 1.5–8(–12) cm long, 0.7–5(–8) cm wide. Lower surfaces glabrous to sparsely pilose along the veins. Margins entire or sinuate. Petioles 0.6–5(–8) cm long. Stipules absent.

Flowers: Flowers in axillary clusters in the lower part of the plant, in unbranched or rarely branched spikes above, the lower clusters of flowers entirely pistillate, staminate flowers only in the upper 1 cm of the spikes, rarely scattered among pistillate ones. Bracts and bracteoles deltate–ovate, awn–tipped. Flowers unisexual; plants monoecious. Calyx of (4)5 sepals; sepals green, those of staminate flowers broadly lanceolate or lanceolate–oblong, apex acuminate, only the midrib green, those of pistillate flowers oblong or spatulate–oblong, apex obtuse or sometimes acute, mucronulate. Corolla (petals) absent. Stamens (2)3–5, distinct; anthers dithecal. Ovary superior, 2–3(4)-carpellate, the carpels connate to form a compound, 1-celled ovary; ovule placentation basal, free-central, or rarely apical; style 1, often lobed; stigmas 3.

Fruit: Utricles with circumscissile or irregularly dehiscient; or indehiscent; 2–3 beaked at apex; ovoid; with a short inflated neck below base of style; 1.5–1.8 mm long; dehiscent with a circumscissile lid; the lid rugulose near the line of dehiscence. Seeds 1 per fruit; the surface usually lustrous; endosperm essentially absent; inconspicuously reticulate.

Ploidy: 2n = 64

Habitat: In disturbed sites.

Elevation Range: