The City of Toronto is conducting an aerial spray this week in order to manage the high levels of European gypsy moth expected in parts of the city. To conduct the treatment, a helicopter will spray from approximately 15 metres above the treetops, completing two applications, only days apart.
The European gypsy moth is an invasive insect from Europe and Asia. It was brought to North America in the late 1800s for experiments regarding silk production, and after escaping captivity went on to establish itself across much of the northeast.
Hungry gypsy moth caterpillars eat leaves, and high levels of them can lead to the widespread loss of leaves on trees and other plants, leaving the trees susceptible to disease or attacks by other insects.
The first spray will cover the area south of Eglinton Avenue West and west of Kipling Avenue, between Warrender Avenue and Princess Margaret Boulevard in Etobicoke. It is scheduled for Thursday, May 28 between 5:30 and 7:30 a.m. The city issued a public notice about the spray here.
The city’s website provides an interactive map where you can enter your address to find out if you are in an area due for a spray.
Last year, areas in wards 1, 2, 3, 4, 11, 12 and 15 were at high risk of infestation and received an aerial spray treatment. Those areas included large parts of Etobicoke near the Humber River and areas adjacent to the Don Valley such as Rosedale.
This will be the sixth aerial spray by the city since 2007, and will be conducted using a product that contains bacillus thuringiensis subspecies kurstaki (BTK), a naturally occurring bacteria found in soil.
BTK has been approved by Health Canada for aerial use over urban areas. Previous sprays in Toronto have not resulted in any reported health impacts, but some sensitive residents could experience skin, eye or respiratory irritation.
According to Health Canada, BTK is only effective during the caterpillar stage of the gypsy moth life cycle. It does not affect adult moths, butterflies, other insects, fish, birds or mammals. There is no threat to pets who are exposed to or ingest BTK.
