Poison Ivy – Galls on Leaves

Q: What in the heck is going on with these poison ivy leaves? They look to be covered with warts.

A: The warts are caused by gall making eryophid mites. These tiny creatures wound the leaf and insert eggs. Leaf tissue grows around them in these characteristic forms.

The infestation doesn’t hurt the leaves. I wish it did….the world might be a better places with a few less poison ivy plants!