Mystery on Oak Ridge

This weekend, days before Halloween, I walked our woods--catching up on many areas I don't regularly see.
My eyes were focused on the ground, where fallen leaves now obscure every last bit of dirt. Hickories and oaks make up most of our woods, with a few maples thrown in for occasional color. Even in a colorless landscape, their different shapes and textures are beautiful.
One tree seemed to be the only of its kind--maybe a chestnut oak? Whatever it is, something seems to have made a meal of it.

Rounded holes, the size of a small pea, are in almost every leaf.
The green leaves above show them, too--as light filtered through this odd patterning.


I'd seen caterpillars feeding on different oaks earlier in the summer--but their ravenous eating devoured entire leaves, not small nibbles. And, what sort of creature takes a bite out of the middle, when the edge would seem to be an easier mark? It's like taking a bite out of the center of a pizza!
Hmmm.