Recognize poison oak by the leaves composed of three leaflets with hairs on the underside. Leaf color varies depending on the time of year and can be green, yellowish, bronze or red. Leaves occasionally exhibit five or seven leaflets.Continue Reading
Poison oak grows in the Eastern and Western parts of the United States and produces green-white or tan berries. The Atlantic variety presents hairs on the underside of the leaves, which distinguishes it from poison ivy. It grows in a shrub-like manner, and leaves generally occur in groups of three. Individual leaves have a lobed or rounded shape.
The western variety grows from the Pacific Coast to British Colombia and into Mexico's Baja California. It grows as a vine or shrub and represents the most common woody shrub in California. The plant propagates by seed or rhizome. Leaves exhibit three leaflets, but the leaf edges can have toothed, lobed or scalloped edges. A single plant may exhibit all three types of leaf edges.
Poison oak belongs to the genus Toxicidendron, consisting of shrubs, trees and vines that include poison ivy. Oily sap contained in poison oak may create an allergic reaction in individuals that causes rash and itching by touching the plant or anything exposed to the sap.Learn more about Gardening & Landscapes