This is widely distributed in mesic woods of eastern states, especially from mid-Atlantic to midwestern regions, but it is rare to absent on most of the southeastern Coastal Plain (K). It does not generally occur in more disturbed woods that have been exposed to dense deer populations or livestock. In Ky. all plants are probably typical purpureum (with 2n = 20 as in other species of Eutrochium). Other variants may be recognizable, especially to the west and north, and hybrids with other species have been reported (F, FNA 21, W). With a long history of diverse medicinal uses, purpureum, or other species of Eutrochium, are known to contain potent furanocoumarins and pyrrolizidine alkaloids (Habtemariam 1998, Herz 2001, Roeder et al. 2015).