The European Gypsy Moth is a major forest pest concern because the caterpillar, or larva stage of the insect, eats the leaves of trees, defoliating them which makes them more susceptible to disease and damage from other insects, like tent caterpillars. Continued defoliation of trees can lead to their decline and eventual death.
A single gypsy moth caterpillar can eat an average of one square metre of leaves.
Knowing the gypsy moth’s lifecycle is important to know how to manage its spread. There are four main stages of the gypsy moth lifecycle: larva/caterpillar, pupa, adult moths, egg masses. Scroll down for specific stage-centric methods to capture and remove gypsy moths and limit the pest’s spread.
We all need to work together to best control this pest.
What is the City doing?
The City manages invasive pests according to trends, data collection and impact of the pest.
Currently, gypsy moth is isolated to two pockets in London that are now being monitored.
Last fall egg mass surveys were completed on City trees, such as in parks and along boulevards, to provide a data driven approach to managing the pest.
Several locations in the Byron area were identified as experiencing populations outside of acceptable parameters and projected a gypsy moth increase in 2020. These locations were targeted for manual egg mass removal on City trees, combined with education and information for the community.
The City is taking an Integrated Pest Management (IPM) approach. This means we are using different management techniques to address the pest population starting with the least harmful to the environment. At this time, spraying is not part of the IPM.
What can residents do?
Property owners are responsible for managing trees (and pests) on their property. They are encouraged to review their private trees and take action to remove gypsy moths and reduce the risk of infestation as caterpillars grow larger, and later in the summer, turn into moths and begin to breed.
Get to Know the Gypsy Moth and its Life Cycle!
The earlier and more often the pest’s life cycle can be interrupted the more successful we will be in managing the pest.
We are currently in the caterpillar phase.
What to look for: The caterpillars of the gypsy moth are dark colored and hairy. They have five blue dot pairs and six red dot pairs on their back. This is the classic characteristic they exhibit that no other moth or caterpillar has. They go through 4-5 "molting" events where they shed their skin and each time, they get bigger.
Click on each season below for detailed methods to capture and remove gypsy moths.