Scale insects are “sucking pests,” which means they extract fluids from plants using a needle-like mouth. You may also notice that it is dropping leaves during summer or that the leaves seem spotted. If you look closely, the scale may be found on the plant’s twigs, stems, leaves, and trunk.
Female Euonymus scales are around 1/16 inch long and dark to brown-grey. Their body is shaped like oyster shell.
Conversely, males are smaller (about 1/32 inch long), white, and rectangular in shape.
These armored scales may fully encrust twigs and leaves when they are numerous. When approaching a plant, white males frequently stand out and aid in identification.
Host plant:
Euonymus scales are major pests of various attractive plants, including Euonymus species such as burning bush and winter creeper, English ivy, holly, honeysuckle, lilac, and pachysandra.
Damages caused by Winged Euonymus Scale:
This scale feeds on at least 29 plant taxa, according to ScaleNet from the United States Department of Agriculture, but is mainly a pest exclusively on Euonymus species in California. The scale consumes leaves and green stems, most notably E. japonica. Scale feeding causes brownish to yellow leaf patches and severe yellowing throughout, And Prolonged large scales cause E. japonica’s progressive deterioration and, in some cases, death.
Life history and habits:
The Euonymus scale includes three life stages: egg, nymph, and adult. The scale overwinters as adult females, which hatch into orangish crawlers that emerge over several weeks in the spring. Female larvae go through two increasingly bigger immature stages, while males go through four juvenile stages before becoming adults. Each year, the Euonymus scale has two or three generations.
