Erect annual herb, mostly up to c. 90 cm. (rarely to 1.5 m.) tall. Stem rather slender to stout, usually branched, angular, glabrous or increasingly furnished upwards (especially in the inflorescence) with short to rather long, multicellular hairs. Leaves glabrous, or thinly and shortly pilose on the inferior surface of the primary venation, long-petiolate (petioles up to c. 8.5 cm. long, sometimes longer than the lamina), lamina ovate or rhomboid-ovate, 1.5–8 (12) × 0.7–5 (8) cm., blunt or retuse at the apex with a distinct, fine mucro formed by the percurrent nerve, cuneate (usually shortly so) at the base; leaf axils without spines. Flowers green, in the lower part of the plant in axillary clusters 4–10 cm. in diam., towards the ends of the stem and branches the leafless clusters approximated to form simple or (the terminal at least) branched spikes c. 3–15 (25) cm. long and 6–8 (10) mm. wide. Lower clusters of flowers entirely female, the spikes generally showing a few male flowers at the apices only (rarely in more than the apical 1 cm.), occasionally with male flowers also scattered among the lower female flowers. Bracts and bracteoles deltoid-ovate, pale-membranous with an erect reddish awn formed by the excurrent green midrib, bracteoles somewhat shorter than or subequalling the perianth, rarely slightly exceeding it. Perianth segments (4) 5, those of the female flowers c. 1.5–2.75 mm. long, narrowly oblong or spathulate oblong, obtuse or sometimes (particularly those approaching the male flowers) acute, mucronulate, frequently with a greenish dorsal vitta above; those of the male flowers broadly lanceolate or lanceolate-oblong, generally acuminate, only the thin midrib green. Stigmas 3, flexuose or reflexed, c. 0.75–1 mm. long. Capsule subequalling the perianth, ovoid-urceolate, with a short inflated beak below the style base, c. 1.5–1.75 mm., circumcissile, the lid strongly rugulose below the neck. Seed 1–1.25 mm., compressed, black, shining, faintly reticulate.
