What is this?



This browning of the leaves? These aren't my trees, but I have this same browning on some Midwest crabs I bought this year. I never had it before.
I agree with MO looks like sunburn or windburn
The interesting thing is I have my new grafts and some seed started pear next to them and those are fine. They are watered regularly in high om soil.
The only difference is the sick looking trees are in Potted, but the pots are buried. They were also mailed bare root in spring, maybe that hurt them?
Have you sprayed any chemicals them or anything near them? Looks like a burn of some sort to me.
Are the roots circling in the pots?
I don't think so, it seems like that leaf coloring is distinctive.
Oak wilt?

Although it looks to dark. We have it in the woods behind our home and it has spread to a false horse chestnut I planted.
This is Oak wilt at my place. It mainly affects oaks but I have it on this false chestnut and I've seen it on a few sassafras trees.

No way to combat it other than cut it out and burn it. This tree is a goner.