This diploid (2n = 20) occurs widely on wet fertile soils in eastern and central North America. Occasional hybrids with serotinum (X truncatum Muhl. ex Willd.) are scattered widely across east-central states (Tucker & Dill 1989), and have been found in MARI, NELS and ROWA (M). These hybrids include plants named E. perfoliatum var. cuneatum Engelm. & Gray or, misleadingly, E. resinosum Torr. var. kentuckiense Fern. E. perfoliatum is particularly well-known as a medicinal plant with varied uses, probably involving its unusual sesquiterpen-lactones, phenolics and polysaccharides (Sharma et al. 1998, Herz 2001, Mass et al. 2011, Roeder et al. 2015).