University of Illinois Extension
University of Illinois Extension - Selecting Shrubs for Your Home
Winged Euonymous Scale
Lepidosaphes yanagicola
Oystershell scale
Severity: 2 out of 5
Frequency: 1 out of 5
Symptoms: This scale can cause premature leaf drop, branch die back and cause the plant to become more prone to winter injury. It is found between the "wings" or bark ridges. It does not move to the plant's leaves.
Cycle: It is an armored scale whichoverwinters as an adult and lays its eggs in June. Eggs may be laid for up to a month. Mating occurs before frost.
Management: Dormant oil spray is effective, as well as insecticides sprayed when the eggs hatch and the crawlers are active. This scale is commonly found primarily on only a few branches of the plant, allowing selective pruning to be an effective control method.
Associated shrubs: