Toxicodendron vernix aka Poison Sumac

Toxicodendron vernix, also known as poison sumac or swamp-sumach, is a deciduous, erect shrub or small tree that grows up to 9 meters (30 feet) tall. It was previously classified as Rhus vernix. The plant is also called thunderwood, especially in the southern United States. The leaves are dark green, alternate, and compound with 7-13 leaflets that are oval-to-oblong, acuminate, cuneate, undulate, with a glabrous or slightly pubescent underside. The stems along the leaflets are red, and new bark is light gray, while the bark of an older plant is darker. Its greenish-yellow flowers grow in dangling panicles, while the subglobose fruits are whitish-gray, flattened, and about 0.2 inches (0.5 cm) across, attracting birds and rabbits. The fruit and leaves contain urushiol, an oil that causes an allergic rash upon contact with human skin and mucous membranes. Inhalation of smoke from burning the plant may cause respiratory difficulty and extreme pain. However, the plant is not toxic to animals and is eaten by birds and other animals when other food is scarce, especially in winter.