Penn State Extension


Boxwood Psyllid

Cacopsylla busi (Linnaeus)

The boxwood psyllid is a common pest of boxwood, Buxus spp. It is not considered as destructive as other boxwood pests. American boxwood B. sempervirens appear to be most susceptible to this pest.


The eggs are small, orange, and spindle-shaped. Nymphs are covered with a white waxy secretion, which readily distinguishes them from other insects that attack boxwood. Adults are light green insects that are about 3 mm long. Both nymphs and adults have piercing-sucking mouthparts.

Life History

This species overwinters as eggs. They are laid between bud scales of the host plant during early summer. Eggs start hatching as soon as buds begin to open in early spring. Young nymphs immediately begin feeding by removing plant fluids from tender foliage. Small nymphs develop on expanding foliage. Leaves become cupped and several nymphs may be enclosed in a pocket of foliage. Nymphs usually mature into adults by early June. After mating, females deposit eggs, that overwinter on the host plant. One generation occurs each year in Pennsylvania.


Feeding damage is very noticeable due to leaf cupping that young nymphs produce on host plants. The leaf cupping results from injury done to leaf tissue as it is developing in rapidly growing leaves. Occasionally, young twig growth is affected by this species.


Treat affected host plants with registered insecticides when nymphs are present in early May.


Pesticides are poisonous. Read and follow directions and safety precautions on labels. Handle carefully and store in original labeled containers out of the reach of children, pets, and livestock. Dispose of empty containers right away, in a safe manner and place. Do not contaminate forage, streams, or ponds.

Authored by: Gregory A. Hoover, Sr. Extension Associate
November 2001

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