hole in apple tree

[mabelgrubb]

5-year-old Cox. Blossomed well in April, fruit setting now. Spotted this alarming hole yesterday, can get a finger in the void. Any ideas what did this and is it terminal?

[burnie]

I think it might be canker, not too sure if there's any treatment, in side branches, you remove the afflicted branch, you can't really do that on the main trunk of the tree. It will take time for the tree to succumb, but it could infect other trees nearby. If you decide to remove the tree, the wood will need burning to kill the canker.

[nickdub]

Definitely canker - probably original infection got in when some sort of mechanical damage to the bark happened.

It's not any sort of increased risk to other trees as long as you don't transfer it yourself via tools like secateurs - there's always some canker around.

If it was my tree I'd try slitting the good bark vertically up the trunk on the opposite side to the canker hole. You do this by inserting the point of a sharp knife just above ground level and running that point up the trunk slitting the bark to well above the level where the canker is. The idea behind this is the scar tissue formed in the bark as the wound you inflict heals blocks canker from spreading right round the trunk. If this girdling of the trunk does happen because the canker has spread then everything above that ring will die. Please note that this is not any sort of an official treatment, but I've done it to a number of trees including both trunks and branches, and its always worked a treat.

[ameno]

Cox are, unfortunately, very prone to basically every apple disease there is. They're great to eat, but as a tree to grow, they are truly awful. To be honest, I wouldn't bother with them. There are plenty of Cox-like varieties which have fruit just as good as a Cox, but with none of the problems actual Cox trees have.