06/11/2026
Have you spotted these strange little spheres scattered beneath oak trees lately? They’re called larger oak apple galls, and they’re actually former tiny homes built by the larger oak apple wasp.
A female wasp lays a single egg in an oak leaf bud, and the tree responds by growing this protective “oak apple” around the developing larva. The wasp spends nearly its entire life cycle connected to this oak before eventually emerging through a small hole as an adult.
While they may look alarming at first, these galls are a fascinating example of the complex relationships happening quietly in our forests every day. Next time you’re walking beneath an oak tree, take a closer look at the ground. Nature is full of tiny architecture projects hiding in plain sight.