Poison Ivy Vs. Poison Oak

Poison ivy and poison oak are cousins, which means their effects are similar. The difference between the two comes primarily in their location and in their visual appearance.

Urushiol Oil

• Both poison ivy and poison oak secrete urushiol oil, which causes the itching and rashes. In that sense, there is no difference between the two.

Contact

• Up to 90 percent of the population is allergic to urushiol oil. People can contract it by brushing their bare skin against poison oak or poison ivy or by inhaling smoke from burning poison oak or ivy.

Location

• Poison ivy can mostly be found east of the Rockies in North America, particularly the Southeastern states of the United States. Poison oak usually grows in Western states, though an Atlantic version can also be found in the Southeast.

Appearance

• Poison ivy typically appears as a vine, while poison oak is often a shrub. Both appear in shaded areas with a lot of standing water nearby.

Leaves

• Poison oak and poison ivy typically have leaves in clusters of three. However, both can have five-leaf or even seven-leaf clusters as well.