Distribution: Occurring west of the Cascades crest in southwestern Washington; southwestern Washington to west-central Oregon.
Habitat: Gravelly, well-drained soil at low elevations.
Flowers: May-July
Origin: Native
Growth Duration: Perennial
Conservation Status: Endangered in Washington (WANHP)
Pollination: Bumblebees, bees, beetles
Herbaceous perennial from a stout taproot and short rhizome, glabrous to pubescent with short, stiff, appressed, simple hairs.
Leaves alternate, palmately veined, long petiolate, the lower rotund, shallowly lobed, the lobes with coarse, rounded teeth, the upper with 5-7 lobes to the base, the lobes linear and pointed.
Inflorescence an elongate, narrow raceme, many-flowered, the pedicels about 3 mm. long; calyx 5 lobed, 4-6 mm. long, purplish-tinged, sub-glabrous to thickly pubescent with stellate hairs; petals 5, pinkish-lavender, 5-15 mm. long, clawed, broadly obovate and notched; stamens 40-70, freed from the staminal tube in 2-3 series, the stamens united in groups; ovary superior, the carpels 5-10 in a ring around a central axis; styles equal to the number of carpels, elongate, stigmatic full length.
Fruit: Capsule 3 mm. long, with a beak less than 0.5 mm. long.
PNW Herbaria: Specimen records of Sidalcea nelsoniana in the Consortium of Pacific Northwest Herbaria database
WA Flora Checklist: Sidalcea nelsoniana checklist entry
OregonFlora: Sidalcea nelsoniana information
E-Flora BC: Sidalcea nelsoniana atlas page
CalPhotos: Sidalcea nelsoniana photos