Poison Ivy, Oak, and Sumac
Poison ivy, poison oak, and poison sumac plants can cause a severe skin reaction when their leaves come in contact with human skin. The result of contact with one of these plants is a red, bumpy skin rash, usually on areas of the body where the skin is thinnest, like the arms, shins and face.
Audio Health Library: Poison Ivy/Oak/Sumac
Botanical.com: Poison Ivy
Health World: Medical Self-Care for Poison Ivy, Oak, and Sumac prevent, identify, and treat an outbreak.
Let's Talk about Poison Oak Palo Alto Boy Scout Troop 5.
Poison Ivy, Oak, and Sumac Information Center identify, cure, treat, and exterminate these plants
Poison Oak and Ivy Translation Project "leaves of three, leave them be" and its variants translated into many languages.
Poison Oak! an article in Herbalgram.