Hello,

Various factors, including environmental stresses, diseases, and pests, can cause bark damage on Japanese maple trees (Acer Palmatum). In Michigan, some common causes of bark peeling or damage include:

Environmental Stresses: Such as frost damage, especially from late frosts, can cause the bark to crack and peel. More information at this link:

Japanese Maple - Acer palmatum | North Carolina Extension Gardener Plant Toolbox (ncsu.edu)

Diseases: Anthracnose is a fungal disease that can affect maples, leading to twig and branch dieback. Verticillium wilt, caused by the soil-borne fungus Verticillium dahliae, is another serious disease that can lead to branch dieback. More information at this link:

Disease and Insect Resistant Ornamental Plants: Acer (Maple) (cornell.edu)

Pests: Insect infestations, such as those from the Asian longhorned beetle, can cause larval feeding underneath the bark, interfering with the transport of water and nutrients and potentially killing the tree. More information at this link:

Disease and Insect Resistant Ornamental Plants: Acer (Maple) (cornell.edu)

It’s also possible for squirrels to strip bark, usually in the pursuit of sap or to use as nesting material. However, this tends to be more common in the case of thinner-barked species.

To determine the exact cause of the bark damage on your Japanese maple, it would be best to consult with a local arborist or the MSU Plant and Pest Diagnostic lab in Michigan. They can provide a more accurate diagnosis and recommend appropriate treatment options. Remember to check for any signs of disease or pest activity and consider environmental factors that may have contributed to the damage.

Here are two options:

OPTION 1:

To confirm and precisely identify the problem, I recommend that you email all your images to the MSU Plant & Pest Diagnostics Lab.

IN ADDITION TO YOUR TWO IMAGES, PLEASE SEND THEM CLEAR AND CLOSE-UP IMAGES OF THE:

Trunk

Upper Canopy

The experts there can also provide you with the best treatment options.

Their email is <personal data hidden> - Please include your name – The lab will let you know if they need a sample sent.

FYI – The lab may also ask for additional images.

Their website is at this link:

Plant & Pest Diagnostics (msu.edu)

Their Contact Information is at this link:

Contact Us - Plant & Pest Diagnostics (msu.edu)

This link will explain the details of submitting a sample to MSU Plant & Pest Diagnostics Lab:

Submit Samples - Plant & Pest Diagnostics (msu.edu)

OPTION 2: (More Expensive)

You can consult a local certified arborist for a more detailed onsite assessment and personalized advice. To find a certified arborist in your Zip Code, go to this link:

Find an Arborist (treesaregood.org)