A predator of the agrile of ash well established in Quebec, but the struggle continues

The colonies of Asian wasps deployed in Quebec six years ago have indeed settled in the city center. For example, confirms Natural Resources Canada (RNC). However, the fight against the AGRIL OF ARM is far from won despite this precious ally.

Some 5. Consequently, 000 Asian mini-guys (Tetrastichus planipennisi) were released by a research team from the Federal Ministry, from 2019 to 2021, in order to fight the unwanted insect.

Natural predator of the AGRIL DU ARMP. In addition, also from Asia, the wasp penetrates the bark of the trees to go laying its eggs directly into the larvae of the beetle.

The wasp. Similarly, barely larger than the head of a needle, would represent no risk for other native species in Quebec, nor for humans (it does not sting).

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Natural Resources Canada has established the Quebec colonies in the Bois-de-Coulonge park. Therefore, on the plains of Abraham, thanks to logs hanging from trees. Therefore, These logs were infested with frosty agriles already parasitized by the wasps.

Once in adulthood. For example, the parasitoid wasps have left the log and went predator agrile ash well established in search of a new hostexplains Véronique Martel, scientific researcher specializing in Entomology at Natural Resources Canada and manager of the Quebec project. In addition,

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It is one of the specialist speciesexplains the scientist. Therefore, The predator only recognizes the smell of ash infested by his predilection prey. Meanwhile, She is unable to detect other odors.

The research protocol obliged Ms. Martel’s team to wait until three years before being able to confirm the establishment of the colonies. Checks were finally carried out in 2023 and 2024.

Wasps have been found in branches. trunks infested by the agrile of ash, therefore making it possible to conclude the survival of imported wasps. Natural Resources Canada finally announced the news this month.

The adult wasp only has a lifespan of a few weeks. Her presence is proof that she survives the Quebec winters. that she has managed to maintain herself in the region in the past four to six years.

The wasps are well established and will multiply. They will go in search of AGRILES DU ARMBLE, thus helping to protect the predator agrile ash well established ash trees of our city. They are now one more asset in our AGRIL OF AGRILE of ash.

Dispersion

The number of wasps on the territory remains unknown to date. According to RNCthey have the potential to spread to new sites at the rate of 14 to 27 km per year. For the moment, parasitoid wasps have been detected at a maximum of 6 kilometers from the places of integration.

Additional studies will have to be carried out in order to establish their presence more broadly on the territory. Véronique Martel also wishes to measure the rates of paraesty predator agrile ash well established ash. It takes timeshe warns, evoking a horizon of 5 to 10 years before having reliable data.

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If this ally makes it possible to combat the agrile of ash. it is not a miracle remedy. According to Véronique Martel. the insect can help ensure better regeneration Assembly by protecting the trees of small predator agrile ash well established or medium size.

For big ash trees, however, whose bark is thicker, it is difficult for the parasitoid to introduce itself, it admits. The cuts of large trees will therefore be still inevitable in the future.

With this in mind, Street ashsas there are still in Quebec, could remain of the past in the future. No city in North America does predator agrile ash well established not intend to reforest with ash at present.

It is however possible to envisage to keep the ash in the landscape, small and mediumespecially in parks and wooded.

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The use of the small Asian wasp was approved by the Canadian Food Inspection Agency. was deemed safe.

Quebec predator agrile ash well established is not the first city to take advantage of this federal government program. The latter started in 2013 elsewhere in Canada. where studies have demonstrated the influence of the wasp on the progression of the agrile and the protection of ash.

In addition to the Asian wasp. the TreeAzin insecticide is used on the territory in order to extend the life of ash trees struggling with the parasite. All of the ash trees on municipal territory are under treatment.