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Sooty mold is a fungus, which causes the blackening of the leaves of certain trees. The mold forms on the leaves as a result of honeydew secretions from insects such as whiteflies, aphids and mealybugs. Insect control is the most effective way to prevent the incidence of this disease. To control the insects and prevent the secretion of their honeydew discharge, spray the tree with Bug Buster Insecticide. When spraying the tree ensure that both the top and undersides of the leaves are adequately sprayed. A second treatment spray may be required about 10 to 14 days later depending on the severity of the insect infestation.
To control and eliminate the mold growth that has already developed, spray the tree with Liquid Copper Fungicide. Generally one application of Liquid Copper is adequate for sooty mold control, but a second application about 14 days later may be required in major outbreaks.