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.

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 airtight 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 New Brunswick, Newfoundland, Nova Scotia, Prince Edward Island, Quebec or Ontario, report it immediately.

Report a box tree moth sighting

Where it is

Box tree moth is a regulated pest in Canada. In Canada, this pest is found exclusively on boxwood shrubs.

In the summer of 2023, box tree moth was confirmed on residential properties in Quebec, Nova Scotia and New Brunswick. In the summer of 2024, the pest was confirmed at a residence in Prince Edward Island. Ontario, Quebec, New Brunswick, Nova Scotia, Newfoundland and Labrador and Prince Edward Island are considered the areas regulated for box tree moth in Canada. See a map of the regulated areas for box tree moth in Canada.

What to look for

Life stages of the box tree moth

  • Box tree moth eggs
    Eggs
  • Box tree moth larva
    Larva
  • Box tree moth pupa
    Pupa
  • Adult box tree moth
    Adult

Signs of infestation on boxwood plants

  • Boxwood plant with signs of box tree moth infestation
    Infested boxwood plant
  • Healthy boxwood plant
    Healthy boxwood plant

Signs of box tree moth include chewed leaves, larvae, webbing and sawdust-like debris (frass).

What we are doing

In the summer of 2023, box tree moth was confirmed on residential properties in Quebec, Nova Scotia and New Brunswick. In response to these detections, the CFIA consulted the public on options to expand the regulated area from January 11 to February 10, 2024. After analyzing the comments received, the CFIA added the provinces of Quebec, New Brunswick, Nova Scotia, and Newfoundland and Labrador to the area regulated for box tree moth. In August of 2024, box tree moth was detected at a residential property in Prince Edward Island, leading to the province being added as a regulated area as well. Directive D-22-04 and the Ministerial Order have been revised to reflect the new expanded areas.

Buxus spp. plants for planting may move freely within, and between, the provinces of Ontario, Québec, New Brunswick, Nova Scotia, Newfoundland and Labrador and Prince Edward Island.

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, Quebec, New Brunswick, Nova Scotia, Newfoundland and Labrador and Prince Edward Island are declared places infested with box tree moth.

Collaborative surveillance and community science continue in an effort to reduce the risk of spread in Canada. A national technical advisory committee has been established to discuss next steps and raise awareness of box tree moth with industry and the public. Members currently include the CFIA, the Ontario Ministry of Agriculture, Food and Rural Affairs, Landscape Ontario, Canadian Nursery Landscape Association, Ministère de l'Agriculture, des Pêcheries et de l'Alimentation, Québec vert, and grower representatives.

More information