Why would an oak tree just start dying? No damage to the trunk, no signs of being struck by lightning, I live innawoods and it's the only one on the row that's dying so I doubt it's been poisoned.

>>5008427 (OP)
Soil, root restriction or root wrapping, proper drainage, over watering.

Any signs of disease or anything on the trunk? Looks like they've all been there awhile. Where do you live?

>>5008445
Yeah they were all here when I moved here, some are close to 3' across the base. No, no sign of disease, no mold, fungus etc. I didn't even really pay it any attention until limbs started falling out. I'm in the southeastern US