Hard Scale (Armored Scale)


Hard or Armored Scales are aphid-like insects that produce a hard waxy shell to protect themselves from predators and environmental conditions. Armored scale females resemble legless bumps and damage plants with their sucking mouthparts. The smaller male scales have wings and while in the nymph stage also feed on plants. Female scale continue to feed as they produce hundreds of eggs under each shell . The mature adult female dies, but the eggs survive the winter under the protection of the shell. In the spring and summer of the following year, the eggs hatch into an immature stage called the “crawler” stage. The crawlers, also called nymphs move out from under the shell and find a new location on which to feed. As they settle they begin to produce their hard shell. Armored scales feed primarily on the woody tissue of trees. Unlike soft scales and aphids, which feed from the circulatory system of the tree, armored scales feed on the contents of individual cells. Since they destroy cells, they can cause significant dieback of infected stem tissues and in severe infestations, even the death of trees.