Unlike the other North American Toxicodendron species (the four species of Poison-ivy and Poison-oak), Poison-sumac is unlikely to be encountered by most people since it typically lives in shady swamps and bogs. It is a shrub that may grow to 5 m with leaves composed of 7 to 13 smooth-margined leaflets. It can be found across much of the eastern United States and adjacent Canada. Poison-sumac and its close relatives are well-known for possessing skin-irritating oil (urushiol), which can cause severe allergic reactions in humans.
Poison-sumac is one of just five North American Toxicodendron species now generally recognized: Common Poison-ivy (T. radicans), Western Poison-ivy (T. rydbergii), Eastern Poison-oak (T. pubescens), Western Poison-oak (T. diversilobum), and Poison-sumac (T. vernix) (Gleason and Cronquist 1991; Senchina 2006)
Senchina (2008) reviewed the literature on animal and fungal associates of Toxicodendron in North America.