English Walnut leaf drop - Ask Extension
We have two English Walnut trees that are experiencing a large amount of leaf drop. The leaves show signs of some sort of disease or insect problem. S...
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English Walnut leaf drop #878904
Asked July 26, 2024, 1:28 PM EDT
We have two English Walnut trees that are experiencing a large amount of leaf drop. The leaves show signs of some sort of disease or insect problem. See pictures. Can you tell what the issue is? Thanks
Eaton County Michigan
Expert Response
Hello,
This looks like an anthracnose infection of the leaves, which is common in walnut.
https://www.purdue.edu/fnr/extension/why-are-my-walnut-trees-dropping-their-leaves/
https://www.fs.usda.gov/Internet/FSE_DOCUMENTS/fsbdev2_043706.pdf
Because the disease generally affects only the leaves, no treatment is recommended. Picking up and disposing of fallen leaves off-site (like the garbage) and maintaining air flow in and around the trees is recommended. Because the infection is fungal in nature, most cultural recommendations involve creating conditions where leaves can dry quickly after a rain or morning dew event.
If you have any questions, please feel free to reach out.
Thank you,
-Julie
This looks like an anthracnose infection of the leaves, which is common in walnut.
https://www.purdue.edu/fnr/extension/why-are-my-walnut-trees-dropping-their-leaves/
https://www.fs.usda.gov/Internet/FSE_DOCUMENTS/fsbdev2_043706.pdf
Because the disease generally affects only the leaves, no treatment is recommended. Picking up and disposing of fallen leaves off-site (like the garbage) and maintaining air flow in and around the trees is recommended. Because the infection is fungal in nature, most cultural recommendations involve creating conditions where leaves can dry quickly after a rain or morning dew event.
If you have any questions, please feel free to reach out.
Thank you,
-Julie
