Ann. Bot. Soc. Zool.-Bot. Fenn. “Vanamo” 19(3): 11. 1944.
Plants loosely cespitose. Culms 15–60 cm, distally finely scabrous. Leaves 3–4 mm wide. Inflorescences: proximal bracts shorter than or exceeding inflorescences; spikes overlapping, distinct, contiguous, short-oblong or cylindric, 5–15 × 3–4.5 mm; lateral 2–3 spikes pistillate; proximal spikes separate, erect, short-pendunculate; distal lateral contiguous or separate, not forming dense terminal cluster, of similar length; terminal spike gynecandrous. Pistillate scales dark-brown to black, margins hyaline, ovate, shorter than and as broad as perigynia, midvein same color as body, inconspicuous. Perigynia ascending, green becoming dark-brown or purple-black, veinless, elliptic, 2–2.5 × 1.25–1.5 mm, frequently serrulate, apex abruptly or gradually beaked, smooth or distal margins sparsely papillose; beak 0.2–0.3 mm, shallowly bidentate, serrulate or smooth. Achenes nearly filling body of perigynia.
Phenology: Fruiting Jun–Aug.
Habitat: Open forests, moist meadows, stream banks, occasionally reaching lower alpine tundra (Colorado)
Elevation: 2400–3500 m
Colo., Idaho, Mont., N.Mex., Utah, Wyo.
The illustration in K. K. Mackenzie (1940) as Carex vahlii is C. stevenii. Although morphologically close to C. norvegica and alternatively treated as a race, C. stevenii is ecologically distinct and geographically distant from C. norvegica.