Achillea genus --- Aster Subfamily 2.1
common yarrow (Achillea millefolium) -- in August -- Arthur's Rock Trail, Lory State Park white & cream
common yarrow (Achillea millefolium) -- in April -- Arapaho Bend Natural Area, Fort Collins, CO FC-AB
common yarrow (Achillea millefolium) -- in September -- Parvin Lake State Wildlife Area, CO