Question
Oak tree leaves with s
I saw your answer about "oak leaf galls" but I am not sure if I have the same thing. Attached is picture of several leaves, set on a blue vehicle hood. I've owned this property in the Western Sierra Nevadas for thirty years, and I don't recall seeing these on Quercus Kelloggi leaves.
AnswerYes those are leaf galls caused by insect laying it eggs on the leaf. This looks like a very minor infestation and would not need to be treated. For insect galls to effect the growth or the leaf fall the numbers would be many many times the ones in the picture. This low a population will more than likely not exist next year. No need to worry with this.
