Q: I have been searching the Web for photos or advice from many people and nobody knows for sure what my problem is. I have 8 hollies that line my yard. On the lower trunks there is bark damage. It then appears on the other branch at the exact same level on another tree. All of the trees show some damage and it is only in the exposed part of the tree and not where the branches are thick. Then I have one tree that is completely different and appears as a different problem altogether.

A: I think you have three critters at work:

In pix 1 & 2 the damage is likely from European hornet

see this link

The rectangular damage in 4 is likely from squirrels

See this link

#4 is sapsucker damage

see this link

European hornet damage

European hornet damage

squirrel damage

sapsucker damage