NC State Extension Publications

Description and Biology

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Boxwood psyllids, Cacopsylla buxi, are small (up to 1/8 inch), green, sucking insects that resemble leafhoppers or miniature cicadas. Boxwood psyllids overwinter as first instar nymphs still within their orange egg shells inserted between the bud scales in May and June. Eggs hatch as soon as the buds begin to open and the nymphs begin to feed on the expanding foliage, injecting their saliva and removing plant sap. Feeding injury produces cupping and curling of the leaves, enclosing several nymphs in the leaf pockets. The nymphs also produce white, fluffy secretions. Adults emerge in late May and June and mate. In July or August, female adults deposit one to seven eggs under each bud scale. Although adults continue to feed, they are not as damaging as nymphs.

The boxwood psyllid adult is a small, green, leaf-hopper-like insect that feeds only on boxwood.

Adult boxwood psyllids are small leafhopper-like insects.

Photo by J.R. Baker

This damaged terminal has been opened to show a boxwood psyllid nymph surrounded by white, fluffy secretions and droplets of honeydew.

Boxwood psyllid nymphs are protected within the cupped leaves.

J.R. Baker

Host Plants

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Boxwood psyllids seem to occur wherever boxwoods are grown. In the United States, however, they are most common in temperate areas. Boxwood is the only known host of this pest. Although both American and English varieties are attacked, American boxwoods are more likely to be severely infested. Psyllid nymphs extract sap from buds and young foliage. As a result, terminal leaves of infested plants become cupped and twig growth may be stunted. Since the boxwood psyllid completes its single annual generation early in the growing season, plants sometimes outgrow their injury by midsummer.

Residential Recommendation

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For control, early detection is essential to avoid leaf damage. Insecticides, including Orthene, imidacloprid, pyrethroids, Sevin, and insecticidal soaps are effective and should be applied as the leaves are expanding. Insecticide treatments applied after leaves have fully expanded (mid to late May) will not alleviate this year's damage, but may help to reduce psyllid numbers next year. When used as directed, pyrethroids are very toxic to insects but are not particularly hazardous to humans and pets (other than fish-avoid using pyrethroids around pools, ponds, and streams). Once inserted into the buds, the eggs are difficult to kill. In case of dry weather, irrigate the boxwoods well before treating to prevent damage caused by insecticides.


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For assistance with a specific problem, contact your local N.C. Cooperative Extension Center

This Factsheet has not been peer reviewed.


Professor Emeritus
Entomology and Plant Pathology

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Publication date: Dec. 4, 2013
Revised: Nov. 3, 2023

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