Toxicodendron vernix

Toxicodendron vernix, commonly called poison sumac, is a woody shrub or small tree found in wetlands and forests. It produces a clear oil called urushiol that causes skin irritation, redness, itching, and blisters upon contact for many people. The oil can also be transferred from clothing or equipment. Unlike poison ivy or oak, poison sumac has smooth, pale stems and leaves grouped in pairs or clusters of 7–13 leaflets. To avoid a reaction, it's best to recognize and steer clear of this plant, wear protective clothing, and wash affected skin immediately if contact occurs.