About Ageratina occidentalis (Hook.) R.M.King & H.Rob.
Ageratina occidentalis (Hook.) R.M.King & H.Rob. is a species of flowering plant in the Asteraceae family, with the common names western snakeroot and western eupatorium. This species is native to the western United States, and it occurs across the states of California, Oregon, Washington, Idaho, Montana, Nevada, and Utah, where it grows in several different habitat types. It is a rhizomatous perennial herb that produces fuzzy green or purple stems that reach a maximum height of around 70 centimeters. Its leaves are glandular, triangular in shape, and have serrated edges. The inflorescence takes the form of a dense cluster of fuzzy flower heads. Each flower head contains long, protruding disc florets that come in shades of white, pink, and blue, and does not produce any ray florets. The fruit is an achene a few millimeters long, topped with a rough, bristly pappus.
