Safety/Medical: The entire poison-oak plant is covered with oily resin. Human dermatitis results when skin comes in direct contact with the oil, either by touching the plant or touching something that has contacted it, such as clothing or firewood. 

 Urushiol is the poison present in the oil . Poison-oak does not cause dermatitis in wildlife or livestock, but pets may react to it .  American folklore holds that drinking the milk of poison-oak-fed goats bolsters the immune system against poison-oak because the poison is present in the milk in trace amounts. Drinking the milk probably does not grant immunity, however. Analysis of milk from does fed a straight poison-oak diet for 3 days showed no trace of urushiol. Some urushiol was present in the does' urine, but most was apparently catabolized . Control: Poison-oak is controlled by glyphosate, triclopyr, or 2,4,5-T. Used alone, 2,4-D is ineffective. Goats are an effective biological control . Other: Poison-oak vines sometimes kill their support plant by smothering or breaking it .