Magnolia scab - Ask Extension
Hi, we moved into a home last summer where we discovered our magnolia tree had magnolia scab. We were advised on how to treat it - and used bio advanc...
Knowledgebase
Magnolia scab #871068
Asked June 01, 2024, 3:26 PM EDT
Hi, we moved into a home last summer where we discovered our magnolia tree had magnolia scab. We were advised on how to treat it - and used bio advanced tree and shrub (Imidacloprid) on the tree a few weeks ago. This week I noticed I can feel wet spittle when I sit under the tree and can see shiny wet spots on the surrounding plants and driveway. Is this honeydew from the magnolia scab? Did I treat it improperly? Is there anything else I can do?
Oakland County Michigan
Expert Response
Hello,
Imadicloprid can take some time to be effective. For now, I would recommend inspecting the branches carefully for signs of the scab, or scale. If you do see them, you can spray them with an insecticide when the crawlers are active, in August. The article below describes the pest, and the best times to treat with insecticide.
https://hort.extension.wisc.edu/articles/magnolia-scale/
If you can reach the branches, you may also be able to scrape them from the tree and drop them into soapy water.
Persistence is key! This one might take a few tries to eliminate.
Thank you,
-Julie
Imadicloprid can take some time to be effective. For now, I would recommend inspecting the branches carefully for signs of the scab, or scale. If you do see them, you can spray them with an insecticide when the crawlers are active, in August. The article below describes the pest, and the best times to treat with insecticide.
https://hort.extension.wisc.edu/articles/magnolia-scale/
If you can reach the branches, you may also be able to scrape them from the tree and drop them into soapy water.
Persistence is key! This one might take a few tries to eliminate.
Thank you,
-Julie
