Poison ivy

Poison ivy (Toxicodendron radicans or formerly Rhus toxicodendron or Rhus radicans) is a plant in the family Anacardiaceae. The name is sometimes spelled "Poison-ivy" to indicate with the hyphen that the plant is not a true Ivy or Hedera. It is a woody vine that is well known for its ability to produce urushiol, a skin irritant that causes an itching rash for most people, technically known as urushiol-induced contact dermatitis.