Wednesday, August 25, 2010
The leaves of the magnolia and the plants, lawn and walkway beneath the magnolia are all covered in a black sticky substance. This is Black Sooty Fungus. Basically, the scale insects are dripping Magnolia sap out the end of the insect. The sugars in the sap attract a fungus disease to grow.
Now is an ideal time to treat the scale insects as the crawler stage is more vulnerable to treatment. Once they have moved back to the twigs, they will form a protective shell. Treatments will not penetrate the shell very easily.