General: Perennial, clumped herb from short rhizomes; stems triangular with smooth edges, slightly rough below the inflorescence, 5-40 cm tall, exceeding the leaves.
Leaves: Sheaths tight, short; blades flat, the margins rolled-under, well distributed along the stem, 4-6 mm wide, the lower ones slightly reduced.
Flowers: The terminal spike with male flowers, the lower spikes 2 to 3, with female flowers, unstalked or with short stalks, 1-1.5 cm long, erect; lowermost bract subtending the spikes scalelike, sheathless, with black ear-shaped lobes, shorter than the inflorescence, the upper ones reduced.
Fruits: Perigynia egg-shaped, 2-3.6 mm long, 0.8-2 mm wide, brownish-green, 3-angled, the angles rounded, smooth to somewhat wrinkled, beakless; female scales egg-shaped, shorter or longer than the perigynia, brownish-red to purplish-black, with lighter 3-nerved centres and translucent margins; stigmas 2; achenes lens-shaped, 1.1-1.3 mm long.
Wet margins of streams and pools in the subalpine and alpine zones; infrequent in N BC; circumpolar, N to AK, YT and NT, E to NF and S to ME, NY, CO and ID; Greenland, Iceland, Eurasia.
The table below shows the species-specific information calculated from original data (BEC database) provided by the BC Ministry of Forests and Range. (Updated August, 2013)
