What is the difference between poison oak and poison ivy?

Plants: The shape of the leaf is the only difference. Poison ivy is a smooth border. Poison oak is rugged and shaped like an oak leaf. Both plants have bracts of 3 leaves. Both cause blister like rashes to hands and skin.

Diff plant: They ate different plants that cause similar appearing contact dermatitis.

Poison ivy vs. oak: Poison ivy and oak are two different planst which have an oil whic causes an allergic rash. The characteristic rash you see is the result of your own body's response to the oil, not the particular plant.

Leaf shape: The Ivy has a leaf shape more pointed like an arrow point.The poison oak has rounded lobed. Both have a palmate (palm like) shape with 3 leaflets originating from a central stem.