Q: Our hedge was carefully propagated from the hedge that lines the football field at Sanford Stadium in Athens. Now it has white powdery stuff on the stems. What could it be?
A: Your Dawg-hedge has a bad case of peach scale (or maybe euonymus scale) insects on it, sucking the sap from your shrubs. The infestation looks pretty extensive so you need to battle it immediately.
The first step is to spray horticultural oil (Sun Spray, Volck Oil, etc) thoroughly on the stems now. The oil suffocates scale insects. Repeat in March.
Also in March, drench the soil around the shrubs with the systemic insecticide imidacloprid (Bayer Tree & Shrub Insecticide), following label directions exactly.
In May, evaluate how much control you’ve gotten. Dead scales should be easy to rub off the bark of the shrubs. Live ones will have yellow or pink juice that becomes visible when you mash them with your thumb.
If you have lots of live ones, consider pruning the shrubs down to twelve inches tall and destroying the debris to remove most of your infestation. Continue to spray with horticultural oil every couple of months until the plants regain their health.
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