Insects
Agricultural Extension Service
The University of Tennessee
SP 290-W
Euonymus Scale
Frank A. Hale, Associate Professor
originally developed by Jaime Yanes Jr., former Assistant Professor,
and Harry Williams, Professor Emeritus
Entomology and Plant Pathology
Center: Euonymus leaf showing yellowish spots on the upper surface and four scales. Left: Female and male scales.
Right: Female scale with portion of protective covering removed to show eggs. Crawlers emerge from under the
protective covering and search for a feeding site.
Female
Males
Euonymus Scale
Crawlers
Eggs
Euonymus scale, Unaspis euonymi (Comstock), is the most
reported insect pest of euonymus, pachysandra and American
bittersweet species in the Southeast. Other known host plants for
this insect include hollies, camellia, twinberry, boxwood,
Daphne, English ivy, hibiscus, jasmine, privet, honeysuckle,
Pachistima and Prunus. Winged euonymus is usually free from
this scale.
Damage
Damage is first seen as yellow spotting on the upper surface
of the leaves. The scale insect sucks sap from the leaves and stems.
As the populations increase in number, stems and leaves become
encrusted with the scales. Leaves may drop as a result of serious
feeding damage. Whole branches or the entire plant may die.
SP290-W 1M 6/03(Rev) E12-4615-00-035-03
The Agricultural Extension Service offers its programs to all eligible persons regardless of race, color, age, national origin, sex or disability and is an Equal Opportunity Employer.
COOPERATIVE EXTENSION WORK IN AGRICULTURE AND HOME ECONOMICS
The University of Tennessee Institute of Agriculture, U.S. Department of Agriculture, and county governments cooperating in furtherance of Acts of May 8 and June 30, 1914.
Agricultural Extension Service Charles L. Norman, Dean
Description and Life Cycle
Male scales are white and about 1/32 inch long. Mature
males are small, two-winged insects. The female is 1/16 inch
long, oystershell-shaped and dark brown. Winged males emerge
and mate with non-mobile females. Eggs are lai