Here you can request to determine the cause of the damage. You can view the requests of other users and sort them according to the selected criteria. In addition, you can get information about your request, and you can follow the progress of its current state. If your application was not approved, it had probably been because it was impossible to identify the damage based on the sent photos or because the application does not address our topic - determining the pests of trees and shrubs. We will inform you about the status of your application by email.
Dear Friend, thank you for your inquiry. Several species of mites (Aceria) live on oak trees and cause similar symptoms. Based on the oak species and location, I assume it could be Aceria ilicis. Best regards, M. Zúbrik
Brown spots at the bottom of the leaf and bubbles on the top of the leaf.
Answer
Dear Sara, thank you for your inquiry. The species is an acari (Acari: Eriophyoidea - gall mite) known as Aceria ilicis. It is known to cause damage to oak, specifically Quercus ilex. To control this infestation, please purchase some acaricide from the nearest garden shop and apply it according to the instructions. Best regards, M. Zubrik