Cherry Tree

Gum does sometimes ooze from healthy bark on cherries, I'd wait and see how it does next year. It will die eventually - but not necessarily from this wound. The only things I've heard can live indefinitely are some jellyfish that can alternate between an adult and juvenile state. If it is bacterial canker, there is not a lot you can do with it where it is as the only treatment seems to be to cut it out.

I noticed an oak tree near us with honey fungus one year but it was at least 20years before it fell down. It leaned right across the road and I always speeded up when passing it. There is an old apple tree in our garden, at least 80 years old that has quite deep holes where branches are missing and with some, it must be quite benign, fungus growing on it. Quite a big branch fell off it last year but I'm hoping it will supply apples for many years to come.