I have several varigated pitsporium and pyracantras that has a white,cotton looking substance on them-looks like a fungus-I wash off with water pressure which seems to help. The leaves turn black and die. What is this and how to treat. |
What you describe can be either mealybugs or cottony scale insects. The black on the upper surfaces of the leaves of the plant is caused by honeydew, a sticky substance excreted by these insect pests. It turns black with age and is called sooty mold. If you get rid of the insect pests, no more sooty mold will develop. The best way to control these pests is with horticultural oil. It suffocates them and they will eventually fall off the plants. Be sure to apply according to label directions. Good luck with your landscape. |