Management of gypsy moth populations on City-owned trees

Last summer I received a number of concerns from residents about the Gypsy Moth infestation that areas in Richmond Hill experienced. This insect is a non-native insect that feeds on a variety of tree species such as oak, birch and maple. It is found throughout southern Ontario, including Richmond Hill and is known to have cyclical outbreaks every 7 to 10 years.
Gypsy moth caterpillars eat leaves and when in large numbers, the caterpillars have the ability to remove much or all of the leaf canopy. However, since the canopy has the ability to regrow as the season progresses, long term effects can be reduced or prevented through management techniques.
Managing trees on City property
Street trees that exhibit gypsy moth infestations will be targeted throughout the winter and spring when the moth is most manageable. City staff will be removing egg masses on small to medium sized trees through manual scraping or a specialized portable vacuum to reduce the number of hatched caterpillars in the spring. Watering will occur in the hotter summer months if necessary to further mitigate long term impacts.
Public notification 
Residents on the roads where work is taking place will receive a notification letter which also includes background information on gypsy moths and what they should do if they find gypsy moth on their trees. A copy of the letter is attached.
Information on how to spot an infestation and how to reduce gypsy moth populations can be found at