In mid-May or early June, the town will be conducting an aerial spray in 33 town woodlands with a safe and naturally occurring insecticide to control the Lymantria dispar dispar (LDD) moth infestation, commonly referred to as a gypsy or spongy moth.
Based on population surveys conducted in 2021, Oakville faces extreme levels of LDD moth infestation this year that could affect 358 hectares (885 acres) of town woodlands and result in a significant loss of trees if no action is taken.
LDD moth is a non-native insect considered a major destructive pest in North America.
These insects are a concern because the larvae (or caterpillar stage) can devastate trees and forests by quickly eating large amounts of leaves. Mostly oak trees are affected. When leaves are lost in successive years, trees can die.
Aerial spraying will likely occur in mid-May once the LDD moth caterpillars have emerged and begun eating.
Spraying will be performed by a low-flying helicopter between 5 a.m. and 9 a.m.
Two treatments will be necessary within a few days of each other. Additional ground spraying may occur during the same period to target town trees adjacent to woodlands that have been identified as high-risk for LDD moth presence.
Notification
Aerial spray dates depend on weather conditions and may need to be postponed with little notice. Once dates are confirmed, staff will post the information on oakville.ca and the town’s Facebook and Twitter accounts.
Residents who live near any of the town's treated woodlands can sign up on oakville.ca to receive 48-hour email notification of the spray.
The designated woodlands and trails will be closed temporarily during the spray and reopen immediately after. Aerial spraying will not take place over town streets or residential properties.
No special precautions are required for residents near the spray areas.
Residents may wish to alter their early morning plans such as running or dog walking on spray days or, if preferred, remain indoors and close windows during the spraying.
There may be some temporary noise associated with the low flying helicopter. There are no health concerns with entering the woodlands after trees have been sprayed.
Insecticide use
For decades, municipalities have successfully conducted aerial spray programs using the naturally occurring insecticide Bacillus thuringiensis kurstaki (Btk). It has replaced chemical insecticides in aerial spraying programs worldwide.
Health Canada Pest Management Regulatory Agency and Oakville's pesticide bylaw permits the use of BtK.
BtK is a bacteria which occurs naturally in soil and has no adverse environmental or human health effects. The bacteria is poisonous only to a specific group of insects when ingested during their larvae or caterpillar stage. BtK does not affect adult moths, butterflies, honeybees, pets, birds, fish, or mammals.
Learn more about BtK on Health Canada's Btk Fact Sheet and Natural Resources Canada's website.
Public safety and the health of our environment are top priorities at the Town of Oakville. We understand there might be some inconvenience on the mornings the aerial spray occurs, and communities' patience and cooperation are appreciated.
For more information, visit oakville.ca. For any questions, please contact ServiceOakville at 905-845-6601 or [email protected].