What causes holes in oak tree leaves?
There are a number of insects that chew on oak leaves. If you have experienced gypsy moth in your area, that is one possibility, but without seeing the insect or some other identifying factor such as excrement or a cocoon, it is not possible to make an exact identification. The following websites will provide some information about the most common pests of oaks. This information may help you to identify the pest.
It is important to correctly identify the pest before attempting to treat the tree. For most pests, correct timing of treatment is critical for success. It could be that the pest has finished eating. If this is the case, treatment would be unnecessary.
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