Distribution: Occurring on both sides of the Cascades crest in Washington; Alaska to California, east to the Rocky Mountains.
Habitat: Moist places and streambanks from the lowlands to the subalpine.
Flowers: June-September
Origin: Native
Growth Duration: Perennial
Conservation Status: Not of concern
Pollination: Bumblebees, bees, butterflies, flies, beetles
Several-stemmed, glabrous, fibrous-rooted perennial 3-15 dm. tall.
Numerous, not tufted at the base nor strongly reduced upward, the lower triangular to triangular-cordate, long-petiolate, the upper with shorter petioles and narrower blades; leaf blades 4-20 cm. long and 2-10 cm. wide, usually strongly toothed.
Heads several in a short, flat-topped inflorescence; involucre 7-10 mm high, the principle bracts usually 13 but occasionally about 8. rays mostly 8, sometimes fewer, 7-13 mm. long, yellow.
The large, numerous, toothed, triangular leaves on a tall, lush plant growing in a wet area in the mountains will usually identify this species.
PNW Herbaria: Specimen records of Senecio triangularis in the Consortium of Pacific Northwest Herbaria database
WA Flora Checklist: Senecio triangularis checklist entry
OregonFlora: Senecio triangularis information
E-Flora BC: Senecio triangularis atlas page
CalPhotos: Senecio triangularis photos