United States National Collection of Scale Insects Photographs Archive, USDA Agricultural Research Service.bugwood.org/
Azalea Bark Scale
Eriococcus azaleae (Comstock) - Adult(s) Since its discovery in 1881, the azalea bark scale has become recognized as a prominent pest of azaleas. Infested plants usually appear chlorotic and unthrifty. The bushes are often covered with sooty mold, a black fungus that grows in the honeydew excreted by the azalea bark scales as they feed. Eventually twigs may die back.
As the female azalea bark scale matures, it secretes white, waxy threads, which become felted or matted into a thick covering over its entire body. This covering is called the egg sac, where eggs are laid after mating. As the female lays eggs, its body shrivels gradually. A until the egg sac is almost completely filled with eggs. Eggs are laid in late April. They hatch in about 3 weeks. This new generation matures during the summer and produces eggs in September. Mature females tend to feed in crotches and on twigs. Adult males, two-winged and tiny, tend to feed on the leaves. Azalea bard scales overwinter as nymphs feeding on the bark.