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.
Thank you for your inquiry. This is Erysiphe platani, a fungus commonly known as plane tree powdery mildew or sycamore powdery mildew. It is an invasive species in Europe. While it typically does not cause serious problems, severe attacks can lead to tree decline and reduced plant vigor. Common fungicides may help, but repeated applications are often necessary. With best regards, M. Zubrik.