I need an ID on some spheres on the underside of a young oak tree's leaf. They're on most leaves and they are leaving a discoloured yellow circle on the top of the leaf as well, even though they are firmly attached only to the bottom. These eggs(?) are light yellow with a hard coating and gel like stuff inside. Does anyone know what this is and if it's dangerous to the tree? Thank you
Galls, caused by a gall-wasp. Harmless.
Resin
Thank you. I was talking to a city arborist today at one of the Canada Day events, and he said the same thing. I didn't get back to this forum until now. It is harmless, as you say, but here in Victoria where we have the garry oak population and the ecosystem is a bit tipped anyway, the powers that be are keeping a close watch. The problem is increasing somewhat. There are lots of bugs out there that find the wasp larvae yummy, so that's a plus. Thanks again
