Question
I live in Southern Illinois. My soil is very acidic and does not drain welll. I have a holly tree. Very suddenly (at least to my eyes) several branches of leaves turned yellow, then brown, then were obviously dead. When I looked closer, I noticed a very distinct pattern on the bark moving up the trunk - it looks like a grid of bare spots all the way around the truck. As it spreads onto the branches, the bark is actually peeling away. It's clearly making its way up the tree, starting about 4 feet off the ground.

I know the poor drainage is not good for the tree, but I'm curious what is actually happening.

Any thoughts?

Thanks,
Dave


Answer
Dave,
There are two possiblities for the damage that you are seeing.
The first is damage from the Yellow Bellied Sapsucker. This woodpecker pecks holes, that look almost drilled into the bark, to attract insects to the sap that starts flowing from the wounds. These holes are always in straight lines girdling the trunk of the tree and do damage the cambium layer which can cause the bark to peal off.
The second is a cambial canker that has infected the holly in it's weakened condition.
In either case, I would recommend fertilizng the tree in the spring and again in the fall to maintain as high a level of vigor as possible. Keep an eye on the tree for any leafminer or scale infestations and treat them immediately.
Try to do something about the drainage- limit watering in the area and add soil amendments that will change the soil profile.
Do not be concerned about the acidity in the soil- Hollies, like all other evergreens, love acidic conditions.

Let me know what happens.
Thanks,
Ed Gulliksen