– milfoil, yarrow
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.
Origin: Both native and introduced populations
Flowers: February-October
Growth Duration: Perennial
– pearl yarrow
Distribution: Reported from Washington but no specimens seen; Alaska to Oregon, east in scattered locations across North America to the Atlantic Coast.
Habitat: Roadsides, wastelots, and other disturbed open areas where occasinally escaping from cultivation.
Origin: Introduced from Eurasia
Flowers: May-August
Growth Duration: Annual, Perennial