Sub-category: Cashew family
The species is variable in its appearance and habit, and despite its common name it is not a true ivy (Hedera), but rather a member of the cashew and almond family. The deciduous leaves are trifoliate with three almond-shaped leaflets. Young leaves are reddish when expanding, turn green through maturity, then back to red, orange, or yellow in the fall. The leaflets are somewhat shiny. The leaflets are 3 to 12 cm long, rarely up to 30 cm. Each leaflet has a few or no teeth along its edge, and the leaf surface is smooth. Leaflet clusters are alternate on the vine, and the plant has no thorns. Vines growing on the trunk of a tree become firmly attached through numerous aerial rootlets. The vines develop adventitious roots, or the plant can spread from rhizomes or root crowns. The milky sap of poison ivy darkens after exposure to the air. The yellowish- or greenish-white flowers are typically inconspicuous and are located in clusters up to 8 cm above the leaves.
Poison ivy is a common weed and found in many places including forests, waste/disturbed areas, residential areas, meadows and even near coastal areas. Blooms in summer, produces berries in fall.