| Poison Ivy is not a parasite in the biological definition of the word. The Urushiol oil on its leaves and vines just happen to cause an allergic skin reaction in most humans but does not affect other animals like dogs. Deer can actually eat the plant. A parasite is an organism that benefits living with another organism (the host) which is harmed. Poison Ivy does not live with to humans and neither does their oil, a non living product of the plant. So to sum up: parasite, no - huge pain in the butt, yes. |
