Backyard and Beyond

Andricus quercusstrobilanus on swamp white oak (Quercus bicolor). There’s no common name for this gall-forcing wasp species.
Note the gap here, and the hollows within.
The individual galls brown and shrivel up as they grow. Then they fall to the ground. (I don’t think this is standard for gall wasps in general).
Since this tree had two other similar clusters, I thought it was ok to take a living sample, i.e., no exit holes for the wasp. (Many Cynipid wasps emerge in the fall as a flightless generation. Looks like this species overwinters, however.)
I cut one open.
Behold, the larva!
With something growing on it! So a gall is good protection against the vicissitudes, but it’s not foolproof. There are parasitic inquiline wasps that prey on gall wasps.
There are also parasitic wasps that prey on the parasitic wasps of gall wasps.