Montana Field Guide

Rhizomatous. Stems erect, 50–100 cm. Leaves basal and cauline; blades 4–10 mm wide, yellowish-green, not inrolled. Inflorescence of 4 to 8 well-separated spikes; the lowest bract greater than the inflorescence. Spikes unisexual; the uppermost 1 to 3 male, linear; the lower female, ascending, 2–10 cm long, subsessile to pedunculate, cylindric. Perigynia perpendicular spreading, green to tan, elliptic, inflated, glabrous, 4–6 mm long; the distinct narrow bidentate beak ca. 1.5 mm long; stigmas 3. Female scales acuminate to awned, brown with hyaline margins and pale midvein, smaller than the perigynia. Achene 3-sided, much smaller than the perigynium (Lesica et al. 2012. Manual of Montana Vascular Plants. BRIT Press. Fort Worth, TX).

Abundant in wet soil to standing water of marshes, fens, swamps, around streams, ponds; plains, valleys to subalpine (Lesica et al. 2012. Manual of Montana Vascular Plants. BRIT Press. Fort Worth, TX).