General: Biennial or short-lived perennial herb from a branched stem-base; stems erect, several, branched, stiff-hairy below, becoming glandular in the inflorescence, 0.3-1.0 m tall.
Leaves: Basal leaves lanceolate to oblanceolate, 2-10 cm long, 2 cm wide, slenderly to broadly stalked; stem leaves opposite, 5-10 pairs, lanceolate, the lower ones often larger than the basal, becoming slightly reduced and unstalked above; stipules lacking.
Flowers: Inflorescence of unisexual (the plants either male or female) flowers, rather showy, evening blooming and scented, several to many in open, spreading, leafy-bracted clusters; petals 5, white, stalklike at the bases, the blades 7-10 mm long, narrowly egg-shaped, 2-cleft to about midlength, with triangular appendages at the base; sepals 5, united, forming a downy, sticky tube 15-20 mm long.
Fruits: Capsules egg-shaped-cylindric, to 20 mm long, with 5, 2-toothed valves; seeds about 1.5 mm long, dark bluish-brown, prominently warty-pimply in concentric rows.
Notes: See S. dioicia for discussion of hybridization.
