Eutrochium pupureum; Asteraceae (aster family)
Those wacky taxonomists are always re-naming things. The genus formerly known as Eupatorium contained a large number of species, a few of which I’ll be featuring over the next several days. Colloquially they’re known as joe-pye weeds, thoroughworts, bonesets, and snakeroots. Apparently the joe-pye weeds are now in the genus Eutrochium (for a while they were in the genus Eupatoriadelphus).
There’s a lot of folklore around the medicinal uses of this plant, named for a Native American who used it for a variety of ailments. It’s a plant with a lot of presence, growing to seven feet tall in rich, constantly moist soils all over the eastern half of North America.