An oil called urushiol causes skin irritation when you brush up against this 3-leafed plant, Rhus radicans
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stinging nettles, toxicodendron radicans, toxicodendron rydbergii,... [DOC] [TLE] Toxicodendron radicans - Wikipedia [PAR] Toxicodendron radicans, commonly known as eastern poison ivy or poison ivy, is 
a poisonous Asian and North American flowering plant that is well known for 
causing an itching, irritating, and sometimes painful rash in most people who 
touch it, caused by urushiol, a clear liquid compound in the plant's sap.