Holes in Trees

Q. I have three pecan trees in the Moapa Valley area that has been attacked by something for the last six years after they were planted. It starts with small circular holes, 2 or 3 millimeters in diameter, in the bark.  This holes are often in a line extending horizontally across the trunk or limb.  Then the bark appears to be shredded in concentrated areas.  As the summer season progresses, the tree leaves slowly and progressively turn prematurely brown.  I never see any particular pest on the tree, just evidence of their presence by the damage they inflict.

This same problem seems to affect a plum and nectarine tree which are now dead. One of the trees was affected so badly that I cut the tree off just above the graft about 4 years ago.  It has regrown some limbs and has not yet shown evidence of new pest damage.  The other two pecan trees still show evidence of continuing damage.  I used the Bayer borer worm treatment two years in a row a few years back.  That seemed to help a little, but again, over time, the damage has been recurring. I think I am going to loose another tree soon and all of them eventually if I don't figure out how to fix the problem.  I'd be willing to try replanting all new trees if I could have some confidence that the problem would not reoccur.  Any information or advice you can offer will be appreciated. 

First picture showing bird damage

A. The first picture is for sure damage from birds in the woodpecker family, probably sapsuckers. The second picture is most likely the same but the damage is spaced so closely together it is more difficult to recognize. The third picture is some sort of "mechanical" damage, the same type of damage as the first two and I can only guess that it is from the same thing using the KISS principle.

Second picture showing bird damage very close together and causing a lot of damage

Most of these birds are migratory so you see their damage in the spring usually but it is also possible it is in the fall. I am no ornithologist but I understand their are some birds in this family that live in this area permanently. I only see this damage during migrations but maybe in your location it might be different.

Third picture doesn't show the bird damage as well but I'm guessing this is what is causing this kind of damage

I have had damage to fruit trees for dozens of years and the trees survive and don't seem to be bothered this much at all. I think the reason for that is they grow so rapidly that they recover from this damage quickly.

Williamson's sapsucker might be causing this kind of damage. I no longer have the photo credits for this picture but I took it from the web several years ago.

From the looks of the trees and the environment I can see in the pictures I think your trees are under a lot of stress. This may prevent them from recovering quickly from this damage. It is very important that trees that are damaged get enough water, fertilizer and soil enhancement so recovery is quick and not lingering into succeeding years. They must recover completely in one season of growth. They will do that if they are pushed to do so after the damage has been done.

Sapsucker damage to an Apple at the University Orchard

Each of these holes put into the tree from birds by their feeding must totally heal before the next season of damage. I don't think yours are doing that. Cover the soil beneath the trees with wood chips at least four inches deep and out to a distance equal to the ends of the branches. Water and apply fertilizer sufficiently after you see the damage to push the tree's recovery as quickly as possible.

If you can use a bubbler and basin instead of drip (if you are using drip irrigation) this might help. This will flood the area under the trees and deliver enough water for a quick recovery. Fertilize the trees in late January or February to get the trees into rapid growth before the damage occurs.

Bubbler and basin around a fruit tree with the basin covered in wood mulch

You can also try to put wire mesh around the tree or damaged areas of the trunk but the birds usually then go to limbs. But if you lose a limb at least you don't lose the tree.