Willow Leaf Beetle Infestation - Ask Extension
Hi, we have what we believe to be an infestation of the willow leaf beetle. We brought the bug to Gertens over the weekend and that's what they think ...
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Willow Leaf Beetle Infestation #870336
Asked May 27, 2024, 8:57 PM EDT
Hi, we have what we believe to be an infestation of the willow leaf beetle. We brought the bug to Gertens over the weekend and that's what they think it is. They also felt that this was a significant infestation and advised us to reach out to you for advise. We have a large willow tree that we noticed the leaves starting to wither and then over the last week or so we discovered this bug. I sprayed what I could with Wondercide (it's near our garden and yard where our pets and children are). Then on Friday a couple branches felt of the tree and we discovered just how bad it was. These bugs almost completely cover the leaves and branches. They are also now crawling all over our garden. We believe that they are just falling onto the garden as those plants and flowers seem unaffected, but the bugs are crawling over everything. Thanks in advance for the advice.
Dakota County Minnesota
Expert Response
https://hyg.ipm.illinois.edu/pastpest/200008d.html
http://cues.cfans.umn.edu/old/Web/154ImportedWillowLeafBeetle.pdf
https://bygl.osu.edu/node/405
https://www.pubs.ext.vt.edu/content/dam/pubs_ext_vt_edu/ENTO/ENTO-139/ENTO-417.pdf
https://ecommons.cornell.edu/server/api/core/bitstreams/ab4837fa-a8b3-4496-8dc3-8851da40f406/content
A tree will tolerate loosing all its leaves or having the chlorophyll stripped off for 2 years in a row but if it happens a third year the trees health will be impacted. Spraying a tree as large as yours will require a tree service. Spraying is rarely necessary. Bt is safe for use near or in a garden. Hopefully the information from the links will help you decide what should be done.
http://cues.cfans.umn.edu/old/Web/154ImportedWillowLeafBeetle.pdf
https://bygl.osu.edu/node/405
https://www.pubs.ext.vt.edu/content/dam/pubs_ext_vt_edu/ENTO/ENTO-139/ENTO-417.pdf
https://ecommons.cornell.edu/server/api/core/bitstreams/ab4837fa-a8b3-4496-8dc3-8851da40f406/content
A tree will tolerate loosing all its leaves or having the chlorophyll stripped off for 2 years in a row but if it happens a third year the trees health will be impacted. Spraying a tree as large as yours will require a tree service. Spraying is rarely necessary. Bt is safe for use near or in a garden. Hopefully the information from the links will help you decide what should be done.