Caespitose. Stems erect, 15–70 cm. Leaves basal and cauline; blades 3–8 mm wide. Inflorescence of 2 to 5 ascending spikes; the lowest bract shorter than the inflorescence. Spikes: the uppermost male or bisexual with male flowers below, 1–3 cm long; the lower female, 10–25 mm long, pedunculate, cylindric. Perigynia ascending, green to purple, narrowly lanceolate, glabrous or sparsely setose above, 3.5–4.5 mm long with an entire, indistinct beak ca. 1 mm long; stigmas 3. Female scales purplish to black sometimes with a pale midstripe, shorter and ca. as wide as the perigynia (
Lesica et al. 2012. Manual of Montana Vascular Plants. BRIT Press. Fort Worth, TX).
In Montana we have varieties
ablata (L.H. Bailey) F. J. Herm. and
atropurpurea Dorn.