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Thursday - April 17, 2008

From: St Augustine, FL
Region: Southeast
Topic: Trees
Title: Treatment of black mildew on magnolia
Answered by: Barbara Medford


I think my magnolia has black mildew. How do I treat it?


We are assuming that your tree is the Magnolia grandiflora (southern magnolia), which is native to Florida. We found an excellent website on this plant from the University of Florida Extension Service. Near the end of the article is a section on Diseases, where we found this information: "Magnolias may be subject to leaf spots, blights, scabs and black mildew caused by a large number of fungi or a bacterium, but they rarely require chemical controls. Raking up and disposing infected leaves may reduce leaf spots next year."

For better on-the-spot information and suggestions on control (or the lack of need for it), go to this website from the St. John's County Extension Office. It has phone numbers and e-mail address for you to contact them. If the problem you are having is widespread, they will be aware of it and can offer you publications and advice in your environment.

Magnolia grandiflora

Magnolia grandiflora

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