I need some help identifying what is going on with this pear tree. The owner says this tree was always healthy until he had someone come and root feed it a few years ago. Then he noticed some dying out in the crown. ( I'm guessing that is not the problem.) It looked to have never been thinned out so I started with that. While pruning, I came across a strange zig-zag pattern in the bark, where the tree sent out new growth just below it. I thought it was some sort of borer, maybe pear borer, but there are no tunnels under the zig-zags. Any help would be greatly appreciated. I have included pics of the zig-zags which I pruned off, as well as pics of underneath the zig-zag pattern. Thanks for any help or ideas!