Heavier than usual rainfalls in much of the country have prompted a lot of foliage problems......tar spot and anthracnose are very common this year and they can account for a lot of early leaf drop. Some trees can be heavier affected than others for a variety of reasons, just like some humans can have weakened immune systems and are more prone to health issues.

There is really nothing you can do about it at this stage nor do you even need to treat. It is more weather related than anything and the situation should right itself next year.

Thank You! for a very prompt and appropriate response. I did a quick read on tar spot and anthracnose, which were terms I was unfamiliar with. We did have a very hot and dry summer last year followed by a very rainy spring this year. I am reassured that the tree should be OK.