Spongy Moth

Formerly known as LDD Moth - Lymantria dispar dispar

Help Protect Markham's Urban Forest

Spongy Moth, formerly known as LDD Moth (Lymantria dispar dispar), is a non-native, invasive forest pest that was introduced to North America from Europe in 1869. It was first detected in Ontario in 1969 and has quickly spread across southern Ontario during the 1980’s. Spongy Moth is considered a well-established regional pest in southern Ontario and is known to have cyclical outbreaks every 7 to 10 years.

Although complete eradication of the Spongy Moth is impossible, the City is taking an Integrated Pest Management (IPM) approach to help reduce the Spongy Moth egg mass count and limit the Spongy Moth caterpillar damage, thus helping protect our Markham trees and green infrastructure. This means we are using different management techniques to address the pest population starting with the least harmful to the environment.

The caterpillars tend to feed on the leaves of select hardwood tree species (mainly Oak, Birch and Maple) between the months of early May and mid-July. In rare cases, when their population size is extremely high, the caterpillar will feed on evergreens such as Pine and Spruce.

The diagram below indicates various control methods which can be utilized throughout the season.

Spongy Moth Control Methods

Spongy Moth Caterpillar Image
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