Distribution: Occurring on both sides of the Cascades crest in Washington; British Columbia to Washington, east to the Rocky Mountains.
Habitat: Moderately dry, open places at low to middle elevations.
Flowers: July-September
Origin: Native
Growth Duration: Perennial
Conservation Status: Not of concern
Pollination: Bees, butterflies, flies, apomixis?
Perennial from a short, woody base, 1.5-8 dm. tall, the stems clustered, amply leafy, spreading-hairy throughout.
Leaves triple-nerved, entire, the lower oblanceolate or spatulate, petiolate, mostly deciduous, the other becoming sessile but ample.
Heads 1-13 in a open inflorescence; involucre 6-9 mm. high; rays 65-150, blue or rarely white or pink, 9-18 mm. long and 1 mm. wide; pappus 20-30 bristles, a few of the outer ones shorter.
PNW Herbaria: Specimen records of Erigeron subtrinervis in the Consortium of Pacific Northwest Herbaria database
WA Flora Checklist: Erigeron subtrinervis checklist entry
OregonFlora: Erigeron subtrinervis information
E-Flora BC: Erigeron subtrinervis atlas page
CalPhotos: Erigeron subtrinervis photos