Why are my crepe myrtles turning black? What are these white specs on my crepe myrtles? If you are asking yourself these questions, you likely have crepe myrtle bark scale on your trees. It was introduced to the United States in the mid-2000s in Texas. Crepe myrtle bark scale made its way over to Louisiana shortly afterwards.
How to Get Rid of Crepe Myrtle Bark Scale
Crepe myrtle bark scale affects crepe myrtles more that are unhealthy. Crepe myrtles that are subjected to poor pruning habits (looking at you crepe myrtle toppers) are more likely to get bad bark problems. Maintain proper pruning methods to keep your trees healthy.
The best time to treat is in during spring, between April and May. A soil drench or deep root treatment using a product containing imidacloprid. You can find this in any hardware store. Follow the mixing instructions and treat the area all around the drip line of the crepe myrtle. Be certain to rake back any mulch before treatment. You can rake the mulch back into place once the treatment has dried. Treat it again the following year to ensure you do not have a resurgence.
During the winter, you can use a dormant oil spray when all the leaves have fallen off the crepe myrtle. This should only be used during the winter and it should be a dormant oil containing paraffin, not some of the lighter oil varieties since they will not kill off the scale.
There have been some success with contact insecticides. Insecticides containing bifenthirin have had limited success. This solution works better on younger scale.
Insect growth regulators as a crawler spray are useful in stopping the crepe myrtle bark scale's life cycle. The solutions will have to be used by a professional since they are restricted use products. Products containing pyriproxyfen or buprofezin have had good success in scale crawler control. Apply when crawlers are active and spray to coat the affected area, this is usually spring.
How to Get Rid of Black Sooty Mold
You've killed off the scale, but the black sooty mold remains. The most affordable, and quickest option is to clean it off. Put a couple of tablespoons of dish soap and warm water in a five gallon bucket. Lightly scrub the affected areas with a soft bristle brush that has been dipped in the soapy solution.
Contact us today to have us get rid of your crepe myrtle bark scale problem.