Distribution: Widely distributed on both sides of the Cascades crest in Washington; Alaska to California, east to the Atlantic Coast; circumboreal
Habitat: Common in open, dry to somewhat moist areas from low to high elevations; tolerant of disturbance.
Flowers: February-October
Origin: Both native and introduced populations
Growth Duration: Perennial
Conservation Status: Not of concern
Pollination: Bumblebees, bees, flies, beetles, wasps
Aromatic perennial from a rhizome, 1-10 dm. tall.
Leaves narrow, tri-pinnate, the ultimate segments linear and short.
Heads numerous, small, in a flat-topped inflorescence; involucral bracts imbricate in several series, dry, the margins translucent; rays 3-12, 2-3 mm. long and wide, white or occasionally light pink; disk flowers 10-75, pale yellow, perfect and fertile; receptacle convex, chaffy throughout; pappus none.
Achenes compressed parallel to the involucral bracts.
PNW Herbaria: Specimen records of Achillea millefolium in the Consortium of Pacific Northwest Herbaria database
WA Flora Checklist: Achillea millefolium checklist entry
OregonFlora: Achillea millefolium information
E-Flora BC: Achillea millefolium atlas page
CalPhotos: Achillea millefolium photos