University of Illinois Extension

University of Illinois Extension

Hort Answers

Insect Damage

Winged Euonymous Scale
Lepidosaphes yanagicola

Oystershell scale
Oystershell scale
1 (1 = rare 5 = annual)
2 (1 = very little damage 5 = plants killed)
Winged euonymous scale occasionally occurs in the southern half of Illinois on burning bush. It willattack several trees as well.

Plants Affected
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.

Life 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.

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.

Related Resources
Home, Yard & Garden Pest Guide
Illinois Commercial Landscape and Turfgrass Pest Management Handbook
U of IL - Distance Diagnosis through Digital Imaging
U of IL - Plant Clinic