Gall over the ground in Houston
I’ve always called them simply “woolly oak galls.” That filled my needs, but North Carolina State Entomologist Emeritus James Baker has a much better name. He says they’re the “detachable woolly leaf gall,” caused by the work of the “detachable woolly leaf gall wasp.”
If you’ve grown live oaks you’ve probably seen the marble-sized woody galls that develop on some trees’ twigs. Those are called “woody oak galls,” at least in my terms. And there are scores of other galls common to oaks. They seem to be fertile feeding grounds for gall-forming insects.
Here is Mr. Baker’s complete report. It’s short, and I think you’ll find it to be very interesting. It will tell you what damage this insect does to your live oaks and what you could consider doing to stop them. (I recommend that you not bother with it.)