What’s In My Backyard?

Meet the neighbors: Oak Rough Bulletgall Wasp

Look at the young oak tree in the photos. All of its branches are covered with strange hard bumps! If you look closely, you may notice small round holes on the bumps. These bumps are called galls and they are the work of the Oak Rough Bulletgall Wasp. The female wasps lay eggs on oak branches. The eggs hatch and the tree forms a woody structure around the wasp to protect itself. The young wasp lives in the gall feeding on sticky tree sap until it is fully developed. It then breaks out of the gall leaving a small round hole. Though they do damage the oak tree, these galls are not all bad. Oak galls were used in the past to make ink. The US Constitution was written and signed with oak gall ink!