Yarrow, Western

Achillea millefolium ssp. occidentalis

Formerly Achillea lanulosa., Rhizomatous native perennial forb with small flat flower clusters and fernlike leaves, blooming April to October. Extremely drought tolerant, though very common throughout the U.S. on wet or dry sites. Especially important in western sagebrush-Bluebunch wheatgrass (Pseudoroegneria spicata ssp. spicata) communities. Used on shrublands, prairies, mine reclamation and roadsides at all elevations; also as an ornamental and for pollinator habitat for native bees. Competitive with weeds. Smaller and much less aggressive than the introduced White yarrow (A. millefolium).