I have 3 large mature white oaks about 2.5 feet in diameter each. They are in somewhat of a row about 25' apart (roots and branches touching). Oak 1 in years past would have a branch lose leaves in late summer before the rest of the branches. I assumed it to be a result of drought stress. This year, Oak 2 (middle oak has dropped 1/4 of it's leaves. Oak 3 is healthy. There hasn't been any construction damage over the roots of any of these oaks. Some of the fallen leaves of Oak 2 are speckled with black spots. Most other leaves of Oak 2 are simple brown at base of leave near petiole. I see so reports of oak wilt in this area.