That might be powdery mildew, which is a fungus. On the other hand, the presence of lady bugs could be an indicator that there aphids around, and the Hackberry Woolly aphid could be described as crystal like. Releasing more ladybugs is an excellent idea! Increasing their numbers should knock back the aphid population, in time.
Hi Ann-Margaret,
That might be powdery mildew, which is a fungus. On the other hand, the presence of lady bugs could be an indicator that there aphids around, and the Hackberry Woolly aphid could be described as crystal like. Releasing more ladybugs is an excellent idea! Increasing their numbers should knock back the aphid population, in time.