Eupatorium lancifolium
Eupatorium lancifolium, commonly called lanceleaf thoroughwort or lanceleaf eupatorium, is a North American herbaceous perennial plant in the family Asteraceae native to the south-central United States.
It is related to Eupatorium semiserratum and has sometimes been considered to be part of that species, but can be distinguished by the size and color of the leaves and because it grows in wetter areas.