I think this is from a Besbicus mirabilis, I could be wrong, I wasn't able to find much more about it then photos of the galls.
|I think that the gall is on a white oak leaf.|
Gall wasps stimulate the over growth of tissue so their babies have a safe place to live and grow.
|The top side of the leaf where the gall was attached.|
|The underside of the leaf, where the gall attached.|
|This is where the gall was attached to the leaf.|
|The wasp larva lived here!|
Hope you have a great night!!