Identifying and Preventing the Spread of the Emerald Ash Borer

Identifying EAB

The beetle has a metallic green back and an emerald green underside. Ranging from 8.5 to 14.0 mm long and 3.1 to 3.4 mm wide, the beetle is fairly small and difficult to spot. Due to its small size, detection may be easier by looking for S-shaped lines formed by EAB larva or unhealthy ash trees rather than the insect itself.

S-shaped lines

Description for photo - S-shaped lines

Image depicting the S-shaped galleries (or tunnels) found beneath the bark of an ash that has been infested by the emerald ash borer.

Emerald Ash Borer

Description for photo - Emerald Ash Borer

This image is used to help demonstrate what a fully formed emerald ash borer looks like, its size and the size of exit holes that are found in infested Ash trees.

The beetle is depicted in the center of the image. It is emerald green, has large black eyes, two antennas coming from the head and 6 legs.

To the right of the image, there is a black semi-circle, about 3.5 mm wide, with the text, "exit hole" above it. This shows what an exit hole would look like in an ash tree that has been infested by the emerald ash borer.

Below the exit hole is a black silhouette, showing the shape of the emerald ash borer with the text, "actual size" above the image. Evidently, the images of the exit hole and silhouette of the emerald ash borer are proportionate to the actual size (8.5-14.0 mm).

Help Prevent the Spread

Don't Move Firewood

Slowing the spread of the emerald ash borer will protect Canada's environment and forest resources. It also helps keep international markets open to the forest industry and nurseries in non-regulated parts of Ontario and Quebec and in the rest of Canada.

The emerald ash borer is most commonly spread through the movement of firewood and other infested ash wood products. By moving infested firewood, this invasive species is transported quickly across large areas. Help prevent the spread of pests: Don't Move Firewood.

Federal regulatory measures prohibit the movement of specific materials including any ash material and firewood of all species from specific areas of Ontario and Quebec. Anyone violating these restrictions is subject to a fine and/or prosecution.

The Importance of Ash Trees

Ash trees are an important part of Canada's landscape. They can be found on city streets, woodlots, and in forests across Canada. Not only do ash trees contribute to a city's aesthetic value, but ash wood is used to make furniture, hardwood floors, baseball bats, tool handles, electric guitars, hockey sticks and other materials that require high strength and resilience. Learn how to identify ash trees.

If there is a high presence of the emerald ash borer in your area, and many ash trees have been destroyed by the beetle, try replanting with recommended alternatives to ash trees.

Life Cycle of EAB

Immature emerald ash borers feed on tree leaves, resulting in abnormal slits in the leaves. Their eggs are laid on the bark of branches of the tree on which they establish themselves. Their larvae bore through the bark, feeding on the inner bark and sapwood, eventually forming flat, 6 mm, S-shaped galleries which are filled with a fine brownish coating. The larva can grow from 2 to 5 cm long and the width of the S-shaped gallery increases throughout its life span.

Life Cycle of Emerald Ash Borer

Description for photo - Life Cycle of Emerald Ash Borer

This image underlines the life cycle of the Emerald Ash Borer. It is broken up into 4 main stages. The image contains a circle with images representing the stages placed on the top, bottom, right side, and left side of the circle.

The first stage is represented by an image on the top of the circle. It shows a sketch of eggs on bark of a tree with text indicating, "Eggs are laid in clusters on bark".

The second stage in the Emerald Ash Borer's life cycle is represented by an image of yellow larva, similar to the shape of a snake. The text beside it indicates, "Larva hatches and bores into tree".

The third of four life cycle stages is represented by and image of pupa. Here the emerald ash borer larva is turning into an adult beetle. The pupa is white and shaped like the beetle. The text beside the image states, "Larva becomes pupa under bark".

The final stage contains a sketch of a fully developed emerald ash borer. The beetle is bright green and horizontally placed.

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