What are they?
Gypsy moths are destructive pests. They get their name from their ability to travel by attaching to various objects. They appear in July or August. Males are greyish brown and can fly and survive about one week, mating with several different females. Females are larger and whitish with darker zigzag marks. The female cannot fly and dies shortly after laying her eggs.

Gypsy moth caterpillars (larvae) change looks as they grow. Young caterpillars are black or brown and about .6 cm (.24 inches) in length. As they grow, bumps develop along their backs with coarse black hairs. The caterpillar is easily recognizable in the later part of this stage: charcoal grey with a double row of five blue and six red dots on its back. Feeding ends by early July, and mature caterpillars can be as long as 6.35 cm (2.5 inches).

Should I be concerned?

Gypsy moths are a concern because the larvae feed voraciously, mostly on the leaves of deciduous (leafy) trees, but also on some conifers (evergreens). During the larval stage, a single gypsy moth caterpillar can eat an average of one square metre of leaves.

Leaves play a major role in food production for trees, converting light into food by photosynthesis. Reducing the leaf surface available to capture sunlight causes a loss in food production. Deciduous trees can sometimes produce a second crop of leaves, but after repeated defoliation, trees may die or become so weakened that they are vulnerable to secondary infestations. Evergreens may die after only one defoliation.

The gypsy moth has been found on approximately 500 species of trees. They prefer broad-leaved trees, mainly red and white oak, poplar, and white birch.

Contact us, if you think you might have Gyspy Moth infesting your trees. We will have an arborist assess your trees and provide you with their recommendations. 416-410-8770