Box tree moth
The box tree moth (Cydalima perspectalis Walker) is a serious pest affecting boxwood plants (Buxus spp). It does not pose a risk to human health. Boxwood plants are important when it comes to nursery trade between Canada and the United States and are a major part of Canada's landscape.
Box tree moth spreads primarily through the movement of infested boxwood shrubs and can fly an estimated 5-10 km per year. If you think you have spotted a box tree moth or signs of infestation on a boxwood shrub outside of Ontario, report it immediately.
Report a box tree moth sighting
Where it is
Box tree moth is a regulated pest in Canada. It is established in Ontario in the areas between Toronto and Windsor, and Toronto and Niagara. In Canada, this pest is found exclusively on boxwood shrubs.
In summer 2023, the presence of box tree moth was confirmed on residential properties in Quebec, Nova Scotia and New Brunswick. This is the first time that established populations have been found outside of Ontario.
If you have recently purchased boxwood shrubs in Quebec or Atlantic Canada, check them for box tree moth.
What to look for
Life stages of the box tree moth
Signs of infestation on boxwood plants
Signs of box tree moth include chewed leaves, larvae, webbing and sawdust-like debris (frass).
What you can do
From May to September, inspect your boxwoods for signs of box tree moth. Adults, pupae, mature larvae and leaves with eggs on them can all be removed by hand and destroyed by placing them in soapy water, alcohol or an air tight sealable container. These life stages are not easily controlled through treatments.
Larvae that are feeding on boxwood plants can be controlled with a biological pesticide containing Bacillus thuringiensis subsp. kurstaki. Multiple treatments may be necessary. Consider contacting a local landscaping company for help with treatment.
If you think you have spotted a box tree moth or signs of infestation on a boxwood shrub outside of Ontario, report it immediately.
What we are doing
Box tree moth was added to the List of pests regulated by Canada. Consult the Pest risk management decision (RMD-22-02) to understand why this decision was made, and the directive for box tree moth (D-22-04) for a description of domestic and import phytosanitary requirements.
A Ministerial Order under the Plant Protection Act was established in July 2023 to support enforcement of these regulatory requirements, which include movement restrictions for boxwood shrubs. Ontario is declared a place infested with box tree moth.
Collaborative surveillance and monitoring continues in an effort to reduce the risk of spread in Canada. An Ontario-based technical advisory committee has been established to discuss next steps and raise awareness of box tree moth to industry and the public. Members currently include the CFIA, the Ontario Ministry of Agriculture, Food and Rural Affairs, Landscape Ontario, Canadian Nursery Landscape Association, and grower representatives.
More information
- Pest fact sheet
- Help to find box tree moth (Landscape Ontario)
- North American Plant Protection Organization (NAPPO) pest alert
- RMD-22-02: Pest risk management decision for the regulation of Cydalima perspectalis in Canada
- D-22-04 Box tree moth (Cydalima perspectalis) – domestic and import phytosanitary requirements
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