Distribution: Occurring east of the Cascades crest in Washington; British Columbia to California, east to the Rocky Mountains, Great Plains, and east across Canada and the midwestern U.S. to northeastern North America.
Habitat: Sandy stream banks, lake shores, and moist flats.
Flowers: June-July
Origin: Native
Growth Duration: Annual, Biennial
Conservation Status: Not of concern
Annual or biennial from a taproot and simple or branched crown, the stem 4-7 dm. tall, glabrous below to stiff-hairy above, leafy throughout.
Leaves pinnate, the lower ones with 2-4 pairs of elliptic to oblong leaflets with rounded serrations, 1-3 cm. long, the upper sometimes ternate; stipules well-developed.
Flowers solitary on long peduncles from the leaf axils throughout the upper half of the plant; calyx stiff-hairy, 5-9 mm. broad, the 5 lobes ovate-triangular, 3-4 mm. long, erect; petals 5, yellow, obovate, about equal to the sepals; stamens usually 20, sometimes less; pistils numerous; style terminal, equaling the ovary.
Achenes 1.2 mm. long with a wedge-shaped thickening on one edge about the size of the rest of the fruit.
PNW Herbaria: Specimen records of Potentilla supina in the Consortium of Pacific Northwest Herbaria database
WA Flora Checklist: Potentilla supina checklist entry
OregonFlora: Potentilla supina information
E-Flora BC: Potentilla supina atlas page
CalPhotos: Potentilla supina photos