Distribution: Occurring chiefly east of the Cascades crest in Washington; southern British Columbia to California, east to Montana and Utah.
Habitat: In and around temporary lakes and pools, generally in lowlands and foothills.
Growth Duration: Perennial
Conservation Status: Review Group 1 in Washington (WANHP)
Perennial herb, aquatic to terrestrial; rootstock buried and corm-like, nearly globose, with 2 lobes, corky, brown.
Leaves deciduous, simple, in tufts somewhat resembling grass, spirally arranged on top of stem, erect to spreading, rigid but not brittle, up to 25 cm, linear above base, tapered to apex, bright green with pale to brown or shiny black base.
Sporangia solitary, embedded in enlarged leaf base, less than 1 cm, less than 3/4 covered by a translucent membrane, male or female; male spores less than 10,000, 0.025-0.035 mm, somewhat bean-shaped, brown in mass; female spores 20-200, 0.3-0.5 mm, spheric, white, ridged.