Questions for an Arborist

Asked July 22, 2019, 11:52 AM EDT

I'm having some concerns about our Jane Magnolia tree. There appears to be a type of fungus growing on the branches (everywhere I can see). This fungus is drawing a large number of flies. Any assistance in identifying and treatment would be most appreciated.

Macomb County Michigan magnolia scale

1 Response

Hello,

The white lumps on branches are mature magnolia scale insects. Treatment time for this is coming up soon. On a small tree, say under 13 feet high, you may want to treat the tree yourself- read details here- https://www.canr.msu.edu/news/check_magnolias_for_magnolia_scale_now

You can treat a large tree with a soil drench of imidacloprid as noted in the above link. Be sure to read and follow the dosage directions carefully, and follow all precautions on the label.

The substance drawing flies is the sticky honeydew exuded by the scale insects. This substance will wear away in repeated rain, and will be discarded with the leaves this fall. Next year monitor the tree to be sure all insects are dead and no new ingestation has begun.

You can hire a certified arborist, a professional who has taken training in care, diseases, pests and passed certification tests. He/she will come on site and give a complete diagnosis, can treat the tree for you at the correct time, and provide a plant care plan. Find certified arborists by zip code here—-

www.treesaregood.org

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