I planted 3 of these 1,5 years ago. Just got through 3 days of +90F weather. Trees looked good before, one still does, one has a few brown tinged branches, the worst looks like this.
I am hoping this is heat related.
Thoughts?
You probably already know this, but that is a Chinkapin Oak rather than just a Chinkapin.
There are several different diseases of oak trees, and they can be difficult to diagnose. In some cases it could take a lab to make a positive ID. Look at the link below to lean more. They give a few tips that might help.
Chinkapin oak typically grow around here on thin soil cover over shallow limestone bedrock, so I don't understand why their seedlings struggle in drought and heat...
I planted a bunch of things from early spring until a week ago. I knew the young ones would need water, but not all of them. My soil ranges from loam to clay. I have a water meter so was figuring out which plants needed it and which did not. Since the DCOs are barely established, I checked them. The two that showed OK did not get water, the third was dry and got water. That is the one that looks OK and is 10' from the one in the pictures.
That sudden blackening of the tips and overall greying of the leaves made me think they were wet and then got too hot. This also sometimes shows up as anthracnose, which is typically a secondary stressor.