Inflorescences somewhat con-gested cymes. Pedicels 1-4 mm. Flowers: sepals 5-8 mm; petals 7-9 mm, ca. 1-1.1 times as long as sepals. Flowering summer. Sand dunes; 100-800 m; Oreg., Wash. Variety thompsonii, at one time known only from the type (Gilliam County, Oregon), was documented in the 1980s in Benton County, Washington.