Distribution: Occurring chiefly east of the Cascades crest in Washington; British Columbia south to California, east to Montana and Colorado.
Habitat: Very wet places at mid-elevations in the mountains.
Flowers: June-August
Origin: Native
Growth Duration: Perennial
Conservation Status: Not of concern
Perennial with a solitary stem from the end of a short, horizontal rhizome, the stem 4-10 dm. tall.
Basal and lower cauline leaves well developed and rather long-petiolate, with 11-27 lanceolate and acute leaflets 1-4 cm. long and 2-13 mm. wide, somewhat reduced upward.
Flowers crowded in an elongate inflorescence; calyx herbaceous, 5-8 mm. long, the 5 lobes about equaling the tube; corolla blue, 1-1.6 cm. long and wide, the 5 lobes longer than the tube; style 3-parted, exserted and surpassing the stamens; ovary superior.
Capsule 3-celled.
PNW Herbaria: Specimen records of Polemonium occidentale in the Consortium of Pacific Northwest Herbaria database.
WA Flora Checklist: Polemonium occidentale checklist entry.
OregonFlora: Polemonium occidentale information.
E-Flora BC: Polemonium occidentale atlas page.
CalPhotos: Polemonium occidentale photos.
USDA Plants: Polemonium occidentale information.