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Emerald ash borer

Il est important de prendre en considération que lorsqu'un frêne meurt , ils devient grandement instable au niveau racinaires, c'est pourquoi il est très important de procéder a l'abattage le plus tôt possible afin de limité les situations hasardeuses.

Emerald Ash Borer

The emerald ash borer is an  pest that causes severe damage to ash trees, native to eastern Asia, first detected in Canada and the United States in 2002 (Michigan and Ontario ) but probably he would have arrived on the continent at least ten years earlier. The borer has killed millions of ash trees in southwestern Ontario, Michigan and neighboring states. The borer is a serious threat to the economy and the environment in urban and forest areas of both countries. The emerald ash borer attacks and kills all ash tree species.

This pest capable of flying several kilometers, but the other important factor that contributes to its spread is the transport of firewood nursery stock, trees, barrels, wood with bark and wood chips or bark.


Biological control

The potential for long-term biological control of the emerald ash borer is being investigated. Certain natural enemies, such as parasitoids (parasites that kill their host) and fungal pathogens of insects, could help reduce emerald ash borer populations. Researchers are examining the death rates caused by these pathogens and parasitoids, and methods to increase or decrease their respective populations.

Researchers continue to study parasitoids imported from China to control the emerald ash borer as part of a biological control program. They carried out numerous operations to release 3 species of parasitoids imported to places infested by the emerald ash borer throughout the northeastern United States and Canada. Populations of 3 of these exotic parasitoids have started to colonize some places.

Signs of tree dieback

• tree crown thinning
• decrease in foliage density
• traces left by the adult insect when it feeds on the leaves
• proliferation of suckers on the trunk or branches
• vertical slits on the trunk
• small D-shaped exit holes
• galleries (in S) under the bark filled with fine sawdust


In North America, the emerald ash borer has few significant enemies, and Canadian ash species have limited resistance to the borer. Statistics have shown that the emerald ash borer damages and kills ash populations 1 year or 4 after infestation.

In general, 6 years after the onset of the infestation, 99% of the ash trees on a woodlot have been killed. This mortality increases the chances of invasion of invasive and harmful plants in the forests, in addition to posing a major challenge to the affected urban areas, we only have to think of Montreal and Laval.

Branch samples

Researchers have devised a new census method that involves taking samples of branches in the crowns of trees attacked or likely to be attacked by the borer. This method, which gives a high rate of detection of emerald ash borer infestations, is used by many municipalities and is the preferred method of preventive detection used by Green Tree Services. The method is particularly effective when it is applied in a preventive framework for the detection of the emerald ash borer.

Systemic insecticide

Researchers in partnership with BioForest Technologies Inc., have designed a systemic insecticide to protect individual high value ash trees and ash trees located in isolated areas of contamination. The systemic insecticide is made from oil derived from neem seeds, and received full registration in 2012. Now available on the market, TreeAzin is used by many municipalities and businesses that maintain trees as a tool. their management strategy for the emerald ash borer.

If unfortunately the sign of dieback of the tree shows a loss of leaf mass of over 50%, it will be necessary to cut the ash.It is important to consider that when Ash dies, they became greatly unstable at the root level , this is why it is very important to proceed to the cut as soon as possible in order to limit the hazardous situation, as well as to limit the price of the invoice, because an ash tree having been left for dead for 3 to 4 years the cut will not be prepared in the same way as an ash still having leaves.


This is why it is important to carefully choose the company that will cut your ash trees, especially when it comes to mature trees. Our Graduate Arborists are able to do the preventive inspection during the free estimate , in order to then plan the safest possible felling scenario.

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