Spores on oak leaves
Are the spores on the back side of oak leaves a series problem?
Livingston County Michigan
I have no idea what you mean by spores. Those, if they were there, would be so tiny you could not see them. I am guessing that you are talking about various leaf galls. These are rounded growths on the backs of the leaves caused by small insects.
If this is what you mean, leaf galls are harmless. You have seen all the power and destructive force they have... a bump on the back of a leaf. Oaks and leaf galls have lived together for billions of years and no one was damaged in the process. You will notice that they are a distended portion of leaf, not an add-on. They are of no consequence and leaf galls could be considered "cosmetic."