I have a rather large oak tree and many of its leaves are turning partially brown (it's mid-to-late July). The tree is in Northeastern Mississippi. A few of the leaves are falling off. I have other oak trees and they are not exhibiting this behavior. What might be going on? See photos below.
The symptom is water stress, and it's likely caused by some fungal infection but there isn't really enough to say definitively what it is.
I immediately thought of Oak Wilt, Sudden Oak Death or Biscogniauxia dieback since they're the most prevalent and potentially deadly. Can you check the trunk and lower branches for any abnormal peeling bark or oozing sap? If you happen to see tiny holes, it could also be some shothole borer--but I wouldn't expect that much damage so quickly from borers.
What's in that compost pile? Any wood chips or leaves that came from further away? (If so, it could have introduced some pathogen to the nearby tree...)