What Are Those White Specks on My Crepe Myrtle?
A new pest threatens the South's favorite flowering tree.
There's no denying the crepe myrtle' supremacy as the number one ornamental tree in our region. It seems everywhere in the South a crepe myrtle could be planted it has been. Such popularity comes at a price, however, as it makes it easy for a pest to hop from one tree to another. That's just what's happening now with a new insect pest called the crepe myrtle scale.
Crepe myrtle scale arrived here a few years ago as an accidental import from Asia. Since then, it spread rapidly. It's easy to spot. It looks like a white speck stuck to the bark of a trunk or branch. Thousands of scales encrusting the bark will literally turn it white.
These insects survive by building protective shells over themselves on the bark and sucking the plant's sap. Then they secrete a sticky honeydew that black mold grows on. Under the shells, female scales lay lots of eggs that hatch out spring and summer and worsen the infestation. Infestation rarely kills the target tree, but it does turn it into an ugly mess.
WATCH: What's Wrong With My Crepe Myrtle? 4 Common Problems
What should you do if you discover crepe myrtle scales on your tree now? First, after its leaves drop, apply dormant oil to the trunks and branches. This will smother both adult and immature scales. Next, in late March, apply a systemic insecticide called Bioadvanced Tree & Shrub Insect Control to all your crepe myrtles according to label directions. The crepe myrtle will absorb the insecticide and all scales feeding on it will die.
Crepe myrtle scale has no natural enemies here yet, so this is the only effective control. Once again, Grumpy has saved your garden from oblivion. You're welcome.