Squamish Spongy Moth Aerial Spray Update — Friday, May 1

by Debbie Evans

Community Update · May 1, 2026 · Curated by Debbie Evans, REALTOR®

The first aerial spray application for the Province's spongy moth eradication program in Squamish is scheduled for this morning, Friday, May 1. If you live or have a property near the treatment area, here is what you need to know about the schedule, what is being sprayed, and how to stay informed as the program progresses.

Earlier this spring, the Province of B.C. announced it would conduct aerial spray treatments in both Delta and Squamish to eradicate invasive spongy moths. In Squamish, the treatment covers 121 hectares west of the intersection of Buckley Avenue and Third Avenue, extending to the edge of the Squamish River and just south of Vancouver Street.

Today's Spray — What to Expect

The first of three planned applications gets underway this morning. Spraying begins at first light — typically between 5:00 a.m. and 6:00 a.m. — and is completed by 7:30 a.m. If rain or high winds are present, the application will be postponed to the next suitable morning, sometimes with very short notice.

Recommended Precaution

Stay indoors with windows and doors closed during the spray and for at least one hour after it is complete. Wash hands after going outside, and rinse any fruits or vegetables from the treated area before eating.

The Three-Application Schedule

The program requires three separate spray applications to be effective. Each is spaced approximately 7 to 10 days apart, with exact dates for the second and third applications determined by insect development and weather conditions.

Total spray applications

7–10

Days between each application

121

Hectares treated in Squamish

7:30

A.M. — latest each spray ends

May 1 — Today First application · First light to 7:30 a.m. · Weather permitting
~May 8–11 Second application · Date TBD based on conditions
~May 15–21 Third application · Date TBD · Program ends by June 30

What Is Being Sprayed — and Is It Safe?

The treatment uses Bacillus thuringiensis var. kurstaki (Btk), a naturally occurring soil bacterium. It works by disrupting the digestive system of caterpillars specifically — it does not affect humans, pets, birds, or other wildlife.

Health Canada Approval

Btk has been approved by Health Canada for spongy moth control since 1961 and has been used in B.C. since 1979. It is also approved for use in organic farming. The specific product being applied is Foray 48B, under Pesticide Use Permit No. 924-0001-26-26. Multilingual health information is available through HealthLinkBC by calling 811.

If you have concerns about exposure — particularly if you have a compromised immune system, respiratory condition, or severe allergies — the Province recommends contacting HealthLinkBC at 811 for personalized guidance.

Why This Program Matters

Spongy moths are an invasive species — formerly known as gypsy moths — that feed on tree leaves and cause widespread defoliation of forests, parks, and crops. Moth numbers in Squamish have been increasing for more than two years.

Without an eradication program, it is highly likely spongy moths will become permanent in the province — leading to significant trade implications for agriculture and forestry businesses in B.C. and an increased risk of ecological damage to the natural environment.

Treatments occur only when necessary, as determined by annual surveys using pheromone-baited moth traps. The Province has been conducting eradication programs of this kind in B.C. since 1979, most recently in 2024.

How to Stay Updated

Because spray dates can change on very short notice due to weather, the Province has set up several ways to stay informed:

24-Hour Information Line: Call toll-free 1-866-917-5999 for the latest spray status
Online Notices: 24-hour and 48-hour advance notices are posted at gov.bc.ca/spongymoth
Email Updates: Subscribe to program notifications at the B.C. Spongy Moth news page
Local Signage: LED signs on highways and lawn signs around the treatment area boundaries will also display current status

Frequently Asked Questions

Does the spray affect my garden or vegetable patch?

Btk targets only caterpillars and has no effect on other insects, birds, pets, or people. As a standard precaution, it is recommended to wash any fruits or vegetables from the treated area before eating them. The treatment has no known residual effect on food crops.

What if it rains this morning — will the spray still happen?

Rain or high winds will cause the application to be postponed until the next suitable morning. Delays can happen with very short notice. Check the 24-hour information line at 1-866-917-5999 or the Province's spongy moth website for current status before 5:00 a.m. if you want to confirm.

How do I know if my property is inside the treatment area?

The Squamish treatment zone covers 121 hectares west of the Buckley Avenue and Third Avenue intersection, to the edge of the Squamish River, and just south of Vancouver Street. Maps of the exact treatment boundaries are available on the B.C. government's spongy moth program page at gov.bc.ca/spongymoth.

Is this the same spray program that ran in 2024?

Yes — Btk aerial spray programs have been conducted in B.C. since 1979, most recently in 2024. The active ingredient, the application method, and the Health Canada approval are the same. The treatment areas are determined each year by moth trap surveys and shift based on where populations are detected.

What happens if spongy moths are not treated?

Without eradication, spongy moths are highly likely to establish permanently in B.C. This carries significant economic consequences — spongy moth infestations can trigger trade restrictions on B.C. agriculture and forestry products in export markets, in addition to causing ecological damage to forests and residential trees.

Sources

Province of B.C. — Ministry of Agriculture and Food — Information Bulletin: "Aerial spraying will curb invasive spongy moths in Delta, Squamish," April 13, 2026.
B.C. Spongy Moth News Page — Spray schedule and 24/48-hour notices. gov.bc.ca/spongymoth
District of Squamish — Community notice, Facebook, May 2026.
Squamish Reporter — "Aerial spraying planned in Squamish to combat spongy moth infestation," April 13, 2026.
HealthLinkBC — Multilingual health information line: 811.

Debbie Evans | REALTOR®

eXp Realty | West Vancouver & North Shore Markets

If you have questions about how programs like this — or any local issue — might affect your property or your neighbourhood, I am always happy to talk through the full picture.

westvanliving.ca

This content is for informational purposes only. All spray schedule information is subject to change based on weather conditions. For the most current status, call the Province's 24-hour spongy moth information line at 1-866-917-5999 or visit gov.bc.ca/spongymoth.