There is only one generation per year. The insect overwinters in the egg stage under the female scale. May. Occurs on lilac, maple, poplar, and willow. Adult females overwinter on twigs. Heavy populations of this insect seldom occur due to beneficial insects that attack it.
Young scales appear in the spring.
There is only one generation per year. Heavily infested trees are pale yellow and have an unhealthy appearance. Insects overwinter as eggs beneath the scale covering. Two broods occur, one in May and another in July. Males are long and narrow, with three ridges running lengthwise on their backs.