Flowers: hypanthium obconic, 1.7-2.5 × 2.5-3 mm, glabrous or scattered-pubescent; sepals 4-6 mm; petals white, 2-3 mm; filaments 5-7 mm; styles 8-11 mm. Flowering Mar-May. Stream-sides, woods, open forests, edges of meadows, thickets, roadsides, fencerows; 0-600 m; B.C.; Oreg., Wash.