Not too sure but it's probably something obvious. I thought maybe figs but I don't know.
Years ago DH and I were at the Botanical Gardens, went up a little-used path, and stumbled on a plantation of dying saplings that we didn't recognize - ended up deciding they were an unsuccessful attempt to breed blight resistance into chestnuts. (The BG is also a U-M research facility.) Think I read somewhere that someone else managed to do it.
I don't remember what caused the chestnut blight; it happened before my time. Elms were destroyed by something called Dutch elm disease, which is spread by an insect and can be prevented by spraying. And now we have the emerald ash borer.
