Euonymus Scale
Unaspis euonymi
Description
Euonymus scale is a difficult-to-control pest of Euonymus and Pachysandra. It has piercing-sucking mouthparts which injure plants by removing fluid from non-vascular plant cells. With up to three generations each year, this pest will damage or kill host plants if not managed.
Symptoms & Diagnosis
Euonymus scale feeds by removing cellular fluids from stems and foliage. Damage will appear on foliage as a yellow stippling or spotting. If infestation is severe, defoliation will occur. Continued infestation and defoliation cause plant death.
Treatment
Frequent scouting is effective in detecting Euonymus scale before an outbreak occurs. Proper timing of treatments controls immature scale crawlers. Pruning heavily infested branches will reduce infestation spread. Multiple treatments are required to maintain effective control of Euonymus scale.
Management
Managing plant stress is a crucial component of insect management. Plants can remain healthier and aesthetically pleasing longer by properly managing water, avoiding compaction and grade changes, and controlling disease infestation. Fertilization improves tree vigor.
Affected Species
- Euonymus spp. (Euonymus)
- Pachysandra terminalis (Pachysandra)



