Boxwood: Boxwood psyllid
Photo by: K. Grey
Biology
The presence of the boxwood psyllid is indicated by the cupping of leaves at the tips of terminals.
The white immature psyllids (nymphs) feed on the developing buds and leaves at the tips of branches, causing the characteristic cupping and sometimes killing the buds.
The greenish, aphid-like adult psyllids are about 1/8″ long and jump. Honeydew, a shiny, sticky material produced by the insects, may be present. The honeydew may become covered with a growth of black sooty mold.
English boxwood (Buxus sempervirens) is reported to be somewhat less susceptible.
Management Options
See "Using Integrated Pest Management (IPM) in the Landscape" for successful problem management techniques.
Non-chemical Management
Select non-chemical management options as your first choice!
- Do not force plants into accelerated growth, as psyllids prefer new, succulent growth for feeding.
- Clip distorted terminals to improve appearance of plants. Otherwise, minimize shearing of plants, since it stimulates new growth preferred by psyllids.
- Conserve naturally-occurring predators such as ladybird beetles, lacewings, and parasitic wasps. Avoid use of broad-spectrum insecticides which kill these beneficial insects.
Chemical Management
IMPORTANT: Always read and follow label directions when working with pesticides.
For more information on using pesticides visit :
- Apply when symptoms are first noticed.
- Adequate penetration must be achieved since leaf cupping gives some protection to these pests from pesticides.
Approved Pesticides
If you choose to use a pesticide, some examples of products that are legal in Washington are listed below. Some products are labeled for just INDOOR or just OUTDOOR use, or may allow both uses. Be sure to choose a product appropriate for your situation. Always read and follow all label directions.
Additional Image
Photo by: A.L. Antonelli
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Evidence of noncompliance may be reported through your local Extension office.