Poison ivy is more than a nuisance. For many, it is a serious medical problem, and a condition requiring lengthy recuperation. While poison ivy is active all year, spring and summer are when contact is more likely to occur.
All varieties have three leaves.
They can be smooth or toothed, hairless or hairy, glossy or dull. It can grow as a vine or shrub, and survive almost anywhere. Affected skin reddens and breaks into bumps and blisters, which begin to ooze. The clear liquid from open blisters will not spread the rash or cause others to get poison ivy. The harmful chemical in poison ivy is urushiol.