Distribution: Occurring west of the Cascades crest in Washington; southwestern British Columbia to Oregon.
Habitat: Forest edge, typically where moist and disturbed; generally escaping from cultivation.
Flowers: June-September
Origin: Introduced from Asia
Growth Duration: Perennial
Conservation Status: Not of concern
Pollination: Bees, flies, beetles, wasps
[none provided]
PNW Herbaria: Specimen records of Petasites japonicus in the Consortium of Pacific Northwest Herbaria database
WA Flora Checklist: Petasites japonicus checklist entry
OregonFlora: Petasites japonicus information
E-Flora BC: Petasites japonicus atlas page
CalPhotos: Petasites japonicus photos