Question
I have a large hickory tree in my yard that has small green balls on the leaves on the lower portion of the tree. Inside them are whitish/orange worms or small winged insects. What are these things and should the tree be treated? Thank you.

Answer
Hi Jodi,

You are seeing a gall caused by an insect laying eggs inside the leaf tissue. Your tree reacts to this foreign substance (the eggs) by isolating them in this ball of tissue since it has no idea what what was inserted into its leaves. It is more of a protection mechanism and is a normal response. No treatment is necessary if you do  not notice the leaves eventually wilting, curling or turning brown.