Eastern poison ivy - Toxicodendron radicans - is a woody, perennial vine or small shrub that can be found in fields, pastures, woodlands, farms and home landscapes. As a vine, it attaches itself to trees or other structures with hairy, aerial roots borne along the stem. Poison ivy has compound leaves that occur in threes - trifoliate or three leaflets. Poison ivy is an allergenic plant in the genus Toxicodendron native to Asia and North America. It is well known for causing urushiol-induced contact dermatitis, an itchy, irritating, and sometimes painful rash, in most people who touch it. The rash is caused by urushiol, a clear liquid compound in the plant`s sap. The plant 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 pistachio family - Anacardiaceae.

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