Sorry, I should have been more clear. Yoshinos are an ornamental that's very popular around here, as they are the same variety as the original gift trees from Japan that ring the Tidal Basin. I understand that they are more closely related to plums, but (being a snotty American kid that I am) I don't want plums. I want cherries!

I have done it on Evans and should work for Montmorency, bark grafting. Konrad Here is a link that might be useful: Bark Grafting

Thank you intotheark for letting us know on this Lutowka cherry. I'd be interested to test it for myself. As the Evans, [my bench mark standard]..can you please tell us the size difference, do you have picture side by side? Also production overall in %. As you and me said, Evans cant be beat in it's vigor and production, another nice darker flesh cherry, reliable, is nice to have around. Got this from a friend, ..after all, this cherry didn't originate out of Poland, ..link translated from Polish.... It is very old of unknown origin, possibly French or Dutch Here is a link that might be useful: Åutówka

If the thin layer of inner bark - the xylem - has been completely removed around the trunk circumference then yes, the trees are doomed. This is the primary vascular system for young trees and is responsible for the transport of water and nutrients to the top growth. Grafting is certainly a possibility and you may want to do it soon while there is still life left but I'll let someone else make those suggestions on how and when.