I've tried to grow apple trees on our property many times over the years, and they have always gotten canker and had to be removed. There was a large apple tree nearby that had canker and I assume that was the source. That tree is gone now. But we have 2 cherry trees that also have canker, that give good privacy and we don't want to remove them. Is cherry an alternate host for canker? We want to plant 1 or 2 again, this time on M111 rootstock, which should have a better chance of success. It or they will be somewhat canker resistant. They will be within range of the cherry trees. I'm just wondering if it will all be a waste again.
The canker on apples is usually anthracnose, while on cherries canker is usually pseudomonas. I haven't found rootstock or cultivar of apples to affect canker sucseptibility, but removing the old diseased tree will make a difference. That was likely the spore source of your canker problems.
