General: Perennial, somewhat tufted herb from short rhizomes; stems 15-70 cm tall, usually longer than the leaves.
Leaves: Sheaths tight; blades numerous, borne on the lower part of the stem, 1-2.5 mm wide, flat, the lowermost leaves often reduced.
Flowers: Spikes 4 to 9 in a 3- to 5-cm long, narrow, interrupted inflorescence, occasionally with a few of the uppermost spikes aggregated into a small cluster, egg-shaped, many-flowered, 4-7 mm long, ascending, with both female and male flowers, the female flowers towards the tips, the male flowers inconspicuous; lowermost bract reduced or rarely awnlike, about 0.5 cm long.
Fruits: Perigynia egg-shaped, 2-3.5 mm long, 0.5-0.8 mm wide, dark green or brownish, minutely whitish-dotted, plano-convex, smooth, lightly nerved on both surfaces, unstalked, the beaks about 0.5 mm long, smooth, cleft on the upper surface; female scales egg-shaped, covering about 2/3 of the perigynia, pointed, green, with green midribs; stigmas 2; achenes lens-shaped, 1.2-1.7 mm long, filling the perigynia.
Notes: This is a variable species whose taxonomy and distribution have not been sufficiently studied. Kalela (1965) distinguished the following three subspecies in British Columbia:
1. Plants densely tufted; stems 15-40 cm long, stiff with short stiff leaves; perigynia 2-2.5 mm long, with a dark brown tinge, the margins without wings, with thick walls, coarsely dotted/pitted....................... ssp. alaskana Kalela
1. Plants loosely tufted, stems 30-70 cm long, lax with long, lax leaves; perigynia 2-3.5 mm long, with a purplish or rusty tinge, with winged margins, thin-walled, finely dotted/pitted.
2. Spikes all separated; perigynia without sharp lateral margins and with faint nerves, light olive-green when ripe; achenes entirely filling the perigynia......................... ssp. sphaerostachya (Tuckerm.) Kalela
2. Spikes forming a terminal head, only the lowermost spike remote; perigynia with weak margins and nerves, olive-brown, with rusty-brown spots when ripe; achenes not entirely filling the perigynia.......................ssp. pacifica Kalela
Bogs, fens and wet sites in forests in the montane and subalpine zones; frequent in N BC, rare in mountains S of 54degreeN; circumpolar, ssp. alaskana - N to AK, YT and NT and E to MB; ssp. pacifica - N to AK and S to WA and ID; ssp. sphaerostachya - N to NT, E to NF and S to ME, MS, SC, TN, OK, CO, UT, NV and OR; Eurasia.
