Herbs, annual, cespitose, 0.1--0.55(--0.65) dm. Culms to 100. Leaves to 2.5 cm x 0.1--0.3 mm. Inflorescences terminal clusters, each with 1--4 flowers; bracts subtending inflorescence 2--5, ovate to lanceolate, inconspicuous, 1--2.5 mm, membranous, apex acute to obtuse. Flowers 3-merous; : tepals dark reddish brown, 2--3.2 x 0.4--1 mm, margins unpigmented; inner series nearly equal to or slightly shorter than outer series, acute to acuminate; stamens 3, filaments 0.7--1.3 mm, anthers 0.3--0.5 mm; style 0.2--0.5 mm, stigma 0.4--1.3 mm. Capsules dark reddish, 3-locular, obovoid to ellipsoid, nearly equal to tepals, 1.8--2.9 x 1.2--1.6 mm. Seeds ovoid, 0.4--0.55 mm, apiculate. n = 17.

Flowering and fruiting spring--early summer. Sandy and clayey damp soils around vernal pools, seepage areas, and low spots in fields and meadows; to 800 m; B.C.; Calif., Nev., Oreg., Wash.