Aerial spraying for LDD moths starts this weekend in Toronto

How Toronto is addressing major moth outbreaks Aerial spraying is underway in many parts of Toronto in an effort to protect tree canopies from the invasive gypsy moths.

The City of Toronto will begin spraying biological pesticide on various parts of the city’s tree canopy this weekend in an attempt to control the spread of the highly destructive LDD Moth.

Spraying will get underway around 5:30 a.m. Saturday at High Park, Beth Mcewen, the city’s manager of forestry and natural area management, told CP24 on May 25.

The park will be closed during the spray operation, which will last about three hours.

“(Helicopters) will flying about 50 feet above the tree canopy and spraying a fine mist of biological pesticide called BoVir in High Park,” she said.

Weather-permitting, parts of wards 6, 15, 16, 17, 18, and 21 will be sprayed on Sunday, May 29.

In this case, the city will use insecticide which is non-toxic to humans, birds, mammals, adult moths, butterflies, bees, and other insects.

Anyone concerned about being negatively affected should avoid the area during and after spraying, Mcewen said.

The non-native LDD moth, formerly known as the European Gypsy Moth, feeds on the leaves of trees and can cause extensive defoliation of the tree canopy.

There are several methods to manage these moths including tree injections, egg mass removal, and ground spraying. Aerial spraying is another option when outbreaks occur. The last time the City of Toronto employed this method was in 2020.

In recent years, LDD moth populations have been increasing across Toronto. According to the Ontario Ministry of Northern Development, Mines, Natural Resources and Forestry this is the worst infestation in Ontario in 30 years.

Last summer, a significant portion of Toronto’s tree canopy was decimated by LDD moths. To manage the situation this year, the city will be spraying roughly 80,000 acres of both private and public land in the coming weeks. More dates for spraying will be announced soon.

Visit the City of Toronto’s Interactive LDD moth Treatment Map to see if your area is in a spray zone.

Anyone with additional questions or concerns should contact 311.