Stems 20-70 cm × 3.5-8 mm, glabrous. Roots not or scarcely fusiform-thickened proximally. Leaves: petiole glabrous. Leaf blade lanceolate, 5.8-14.1 × 1.2-2.9 cm, base acuminate or sometimes acute, margins serrulate. Flowers: petals 4-6, 7-11 × 4-8 mm.

Flowering spring (Apr-Jun). Wet meadows, bogs, shallow water of streams and ponds; 0-1700 m; B.C.; Calif., Idaho, Mont., Oreg., Wash.