Answer: Based on your description I am not able to diagnose the problem specifically. It might be a fungal infection or a combination of disease problems. I would suggest you work with your local Penn State cooperative extension to obtain a specific diagnosis, and based on kwowing that, decide what to do. If a chemical control is needed, they will have the most up to date information on what to use and when/how is best to apply it for maximum results. In the meantime, clean up all the fallen leaves from the tree -- both now and this fall -- and put them in the trash to try to limit possible sources of reinfection. I'm sorry I can't be more specific for you long distance.
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