Toxicodendron is a genus of plants that includes species like poison ivy, poison oak, and poison sumac. These plants are known for producing an oil called urushiol, which can cause allergic skin reactions in many people upon contact. They are commonly found in North America and can thrive in various environments, including forests and gardens. The leaves of Toxicodendron plants typically have a distinctive appearance, often with a glossy finish. They can vary in shape and size, but many have a characteristic three-leaf structure, especially poison ivy. Awareness and identification of these plants are important for avoiding allergic reactions during outdoor activities.