asian longhorn beetle around silver maple

Asked August 3, 2014, 1:16 PM EDT

We have a large silver maple that has shed a couple 20" peices of bark that show the tracks of a borer. About 4 years ago I found a asian longhorn beetle on our patio. Is this beetle being a current problem? What can we do to prevent further damage to the tree? Writing from Ann Arbor, MI

Washtenaw County Michigan

1 Response

Hello, (If this response is all run together, I apologize- my word processor is not working correctly right now!) ----- Asian Longhorned Beetle hasn't been reported in Michigan, yet. It closely resembles the Pine Sawyer Beetle. If you have ALB symptoms on a tree, or have captured a beetle, you can report it to: Beth Clawson, MSU Extension, Washtenaw County Educator, Natural Resources 269-657-8213 Or you can call the MSU Diagnostic lab ( 517-355-4536 Here are articles on ALB and what the symptoms are, with pictures --- ----------- ---------- ------------ Your peeling bark can be from many causes, including a frost crack that has allowed the bark to peel off. Silver maples have a naturally peeling bark. Here is some detail on how trees deal with loss of bark from University of Rhode Island Extension: "When a split occurs on a tree, what should you do? In recent years quite a bit of research as been done on closure of tree wounds. These investigations have indicated that tree wound paints are of little value in helping a tree to callus over. For this reason, do not paint or try to seal a split with paint or tar. .... A tree growing with good vigor usually calluses over quickest. Encourage vigor in the tree with yearly spring fertilizer applications and be sure to provide adequate irrigation in hot, dry weather. Bark splits will often close over completely, leaving a slight ridge in the trunk where callus tissue has been produced." (end of quote) The above indicates that a tree will callous over a 1/2 inch to 1 inch wide open area. Your tree can do so if it is otherwise healthy and has the proper amount of water and nutrients. Continue to monitor your trees. If they otherwise appear healthy, they are callusing over on their own. For disease, insects or lightning strikes an arborist needs to be consulted. If the tree is of high value to your landscape, you can consult a certified arborist who can check for disease and insect issues and recommend a treatment plan. Find an arborist by going to then click on the "Find an Arborist" tab. Give the tree good care-- mulch 3 inches deep out to the drip line (don't let the mulch touch the trunk), deeply water the tree during times of drought (a lawn sprinkler is not enough, use a soaker hose). Asian Longhorned Beetle is a serious invasive pest, and I am glad you are watching for it. If you think you see one, do try to capture it, bottle it (don't use any sticky tape or substance), note the date and location, and contact the MSU Diagnostic lab (info above). I hope this information is helpful. Thank you for using our service.