Subject: What sort of gall is this?
Location: Northeast Tennessee
March 28, 2014 7:47 pm
I found this gall on what I believe to be a small oak tree in my backyard. I’m not very familiar with the various types of galls, but I know that they can be caused by wasp larvae or fungi. I’m curious to know the origin of this one.
Signature: Erin
Dear Erin,
We believe this is an Eastern Oak Bullet Gall, which we found pictured on the Henderson State University Plant Gall Page. It is described as: “smooth, spherical galls approximately 1/2 inch in diameter produced by a wasp of the genus Disholcaspis. These galls are very hard because they form from the tough, woody tissues of twigs.” According to BugGuide, the species Disholcaspis quercusglobulus: “Forms round, detachable twig galls, 8-15 mm in diameter, singly or in small clusters, on white oak (Quercus alba).”