Black Sooty Leaf Mold Fungus

Asked October 17, 2020, 10:10 PM EDT

My deck and surrounding yard and plants have been desimmated by this fungus all summer and fall. The leaves of my Maple tree are black. What can I do to prevent this scourge next year?

Jefferson County Kentucky

1 Response

Plants and trees with a scale infestation can attract sooty mold. Sooty mold feeds on sugars secreted by the scale insects as they feed on tree sap. The best way to deal with this is to bring in a sample tree branch with the scale attached to that the type of scale can be identified and then the tree can be sprayed or treated for the scale. once the scale is gone the mold has nothing to feed on so will not continue to be a problem.

You can bring a branch with affected leaves and healthy leaves on the same branch, in a bag into the office at the address below. We have a table out front for you to fill out a plant disease form, after the form has been filled out place in the bag with your sample and leave on the table. As we cannot see you face to face due to CDC guidelines, we check the table several times daily.

There is not an easy way to remove the mold from other plants as there is not a chemical spray that will dissolve the mold that would not harm plants. The deck could be treated with a household mold/mildew product. Make sure the label states it is safe to use on the construction material of your deck.

Feel free to contact our office if you have other questions.

Let me know if I can help you further!

Carol Wilder
Horticulture Technician
Jefferson County Cooperative Extension Service

4200 Gardiner View Avenue

Louisville KY 40213