Could be a few things. Possibly a fungus. Possibly wind dessication.
Gather all leaves this fall and dispose of them. It may be a seasonal
thing and the tree will recover next year. You may try a general
fungicide next year. Keep the tree well hydrated.
HomeOwnersHub.com is a website for homeowners and building and maintenance pros. It is not affiliated with any of the manufacturers or service providers discussed here.
All logos and trade names are the property of their respective owners.