Medicinal Parts: The medicinal part is the herb after flowering.
Flower and Fruit: There are numerous flower heads in terminal, large, and slightly convex cymose-paniculate inflorescences. They consist of 10 to 12 white, inconspicuous florets with bristly pappus whose hairs are arranged in a single row. The fruit is a tufted achene.
Leaves, Stem, and Root: Eupatorium perfoliatum is a perennial herb with a horizontal hairy rootstock. The stems are rough-haired and grow to about 1.5 m. The leaves are opposite, 10 to 15 cm long, lanceolate, crenate, tapering to narrow point and fused at the base. They have …