Diseased Star Magnolia

Asked June 24, 2019, 3:41 PM EDT

My tree has a black sooty looking substance on the trunk and branches. The leaves are not looking healthy either. Can you tell me what it is and how to treat?

Genesee County Michigan yellowing leaves star magnolia black soot

1 Response

What you most likely have is an insect problem, not disease. Most likely magnolia scale and you can read more here: https://www.canr.msu.edu/news/check_magnolias_for_magnolia_scale_now

Black sooty mold can then develop on the insects excrement. Read more here:
https://www.missouribotanicalgarden.org/gardens-gardening/your-garden/help-for-the-home-gardener/advice-tips-resources/pests-and-problems/diseases/black-mildew.aspx

It can get quite ugly and the scale should be addressed to avoid the same thing
happening next year. Correct timing of control is critical and the recommendation is to involve a Certified Arborist, one who specializes in
everything woody. You can find one or more Certified Arborists in your zip code at www.treesaregood.com Click on the Find an Arborist tab.

Good luck!