Emerald ash borers

The emerald ash borer is a narrow, elongated beetle with six legs and a metallic green colour in adulthood. As its name suggests, it is fond of ash leaves. The larva (with a creamy white colour) tunnels under the bark, nearly always causing the tree to die.

Originally from Asia, this borer was first observed in North America in the early 2000s. The larva hide in the planks of transportation crates and pallets as well as in firewood. This is how the insect travels through countries, provinces and cities.

The Canadian Food Inspection Agency (CFIA), in charge of fighting invasive species, has adopted regulations. An individual may be fined up to $50,000 or may be subject to prosecution if he or she moves firewood without authorization from areas affected by emerald ash borers.

Some municipalities affected by emerald ash borers have also adopted control measures. You should check municipal bylaws before cutting down any trees. The same applies if you observe signs of infestation or if you catch this terrible insect. Notify your municipality, or call the CFIA at 1-800-442-2342.

1. Check whether emerald ash borers have infested your firewood

Since this insect is transported in firewood, it’s also through firewood that an infestation can best be prevented. If you’re buying firewood:

• Check first where it came from, and beware of any wood from an infested area.

• Ideally, buy your wood locally and burn it locally.

• Never transport your wood beyond the boundaries of a CFIA-regulated area.

2. Preventive treatment of emerald ash borers

TreeAzin®, a bio-pesticide made from neem seed oil, is fairly effective in repelling emerald ash borers. This treatment, accredited in Canada, must be applied by certified persons. CAA-Quebec Residential Advisory Services can help you find a reliable company in your area. Good to know: A municipality can require you to treat a diseased tree. This is often subsidized.

3. Diversify your trees to protect them better

If you need to plant new trees, avoid ash. Ask at your garden centre. A specialist can help you make a wise choice based on the size of your yard, the direction it faces, your buildings and, of course, your tastes.

The emerald ash borer often has the last word and usually destroys the trees it afflicts. Used preventively, TreeAzin® helps control this destructive pest or at least restrain its zeal. Note that pilot projects involving the Beauveria bassiana fungus may soon provide a new tool for fighting this insect.

Here are some signs of the presence of the emerald ash borer:

• Cracked bark

• D-shaped holes in the bark

• Increased woodpecker activity (revealing the presence of larvae under the bark)

• S-shaped larval tunnels

• Yellow leaves in the summer

• Presence of shoots on the trunk or branches

If you see any of these signs, call on a tree specialist or an employee of your city’s horticulture department to inspect your tree(s) in greater detail. This person can then judge which ones can be saved and treat them. This has to be done by a professionnal certified by the Quebec Ministery of Sustainable Development, Environment and the Fight Against Climate Change.

This should be done during the growth period, between May 15 and August 31. The preventive product is injected at the base of the tree, repeated every two years.

Trees that are very hard hit (from the crown to half the branches) will have to be cut down. It is advisable, however, to avoid cutting during the period when emerald ash borers spread the most, between March 15 and September 30.

Unfortunately, they don’t. Parasite attacks, causing the gradual loss of trees, are not covered. Home insurance policies do, however, provide compensation for loss of a tree caused by fire, lightning, explosion, a vehicle crash, rioting, theft or vandalism.

CANADIAN FOOD INSPECTION AGENCY (CFIA)

Areas Regulated for the Emerald Ash Borer

CONSEIL QUÉBÉCOIS DES ESPÈCES EXOTIQUES ENVAHISSANTES (in French only)

Agrile du frêne