The B.C. Ministry of Forests says these pests aren't picky eaters: they feed on the leaves of more than 300 species of trees and shrubs.
Aerial spray treatments are planned Vancouver Island and Salt Spring Island over the next two months.
The ministry is planning three applications of biological insecticide Foray 48B between late April and mid-June.
In Greater Victoria, spraying is planned for the Gorge-Tillicum, Belmont, Esquimalt and Victoria West neighborhoods.
Each treatment will occur seven to 10 days apart and could take up to two days to complete.
Weather permitting, each spray is expected to begin at dawn and end no later than 7:30 a.m.
On the Saanich Peninsula and up island, the ministry plans to treat:
48 hectares on Salt Spring Island will also be sprayed.
Invasive spongy moths, also known as Lymantria moths, were formerly referred to as gypsy moth.
The active ingredient Bacillus thuringiensis var kurstaki (BtK) is naturally present in urban, agricultural and forest soils in the province.
It affects only moth and butterfly caterpillars after they have ingested it.
Btk was approved for the control of spongy moth larvae in Canada in 1961.
To learn more about spongy moths and the upcoming sprays, click HERE
For information about pesticide-use permits or to see a map of the treatment areas, click HERE