Damage on Honey Locust - Ask Extension
We just noticed a couple of spots on our Honey Locust when the bark is missing, scratched or whatever. This is about 10-12 feet up the tree. we are c...
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Damage on Honey Locust #925766
Asked March 10, 2026, 11:58 AM EDT
We just noticed a couple of spots on our Honey Locust when the bark is missing, scratched or whatever. This is about 10-12 feet up the tree. we are curious as to what could be doing this and if we need to do anything to prevent damage. We love the tree and it provides great shade.
One of the attached pictures shows the entire tree, the other the damage.
Thanks
Yellow Medicine County Minnesota
Expert Response
Thank you for writing.
This may be Thyronectria canker. However an arborist has to make that diagnosis (see signature line). https://extension.colostate.edu/resource/honeylocust-diseases/
I am also concerned about what is under the stones at the base of the tree. If there is plastic or groundcloth, it may be changing the soil bacteria, water to the rootball, or temperature in a manner that stresses the tree and predisposes to disease.
From your picture, the disease appears to be at a stress point where a large branch is creating some stress on the tree. The arborist should assess this as well.
This may be Thyronectria canker. However an arborist has to make that diagnosis (see signature line). https://extension.colostate.edu/resource/honeylocust-diseases/
I am also concerned about what is under the stones at the base of the tree. If there is plastic or groundcloth, it may be changing the soil bacteria, water to the rootball, or temperature in a manner that stresses the tree and predisposes to disease.
From your picture, the disease appears to be at a stress point where a large branch is creating some stress on the tree. The arborist should assess this as well.
