The emerald ash borer (EAB) is a nasty little invader that is currently laying waste to all ash trees in its path. Cities, towns and concerned citizens are all doing their best to fight back but the cost of stopping the emerald ash borer is high.
Unfortunately, the emerald ash borer has few natural predators in Canada, and native ash trees have limited resistance to this pernicious pest. Studies show that EAB’s damage and kill trees within one to four years of infestation. Since its arrival on the shores of Canada in 2002, the emerald ash borer has killed millions of ash trees throughout the continent, and if it continues to spread at its current rate the economic and ecological impact could be considerable. According to Canadian Forest Services (CFS), the cost of treating, removing and replacing trees affected by emerald ash borer could be as high as $2 billion over a 30-year period.
But this is not just a cost problem for cities and towns, it is also a public safety issue. Municipalities are responsible for maintaining the trees on their property, and once an ash tree dies it becomes extremely dry and brittle and can easily topple over, posing a risk to people and property.
Treat or Remove?
EAB is a problem that affects everyone and whether the decision is taken to treat or remove infected trees, there are costs involved.
Ash trees that are not treated with an appropriate insecticide will die as a result of an emerald ash borer infestation. Once the tree has died, it needs to be removed and, depending on its size and position, this can be an expensive and hazardous exercise. The cost of treating an ash tree infested with emerald ash borer will also depend on the size of the tree and the number of trees that are being treated simultaneously.
Martin’s Tree Service can treat ash trees with an injectable insecticide called TreeAzin. Trees will initially need to be treated annually but after a while, it may be reduced to every second year until the EAB population has decreased. This can last for anything from six to ten years before the EAB population has declined enough to discontinue treatment. The Canadian Forest Service has designed a cost calculator to help homeowners decide whether it is more cost effective to treat or remove their ash trees.
Cost of Research
It is not just the cost of removal or treatment of infected ash trees that need to be considered by the CFS and local municipalities. They also need to find funds to cover the cost of research so that scientists can study the survival techniques, spread patterns and habits of emerald ash borers in order to learn how to better manage the problem.
Steady progress is being made with research into long-term biological control measures, including the introduction of natural parasitoids (insect parasites that kill their hosts) and insect pathogenic fungi into ash forests. Mating disruption techniques, using female-produced pheromones, are also being used to disorientate male emerald ash borers and reduce successful mating. The CFS has also been involved in the development of a green-leaf volatile lure as bait for a green prism trap system.
Unfortunately, the cost of the EAB invasion is not just economic, there may also be a potentially devastating ecological price to be paid if the problem is not bought under control. As the ash trees die, the tree canopy is lost, and with it the natural habitat of many species of indigenous birds, animals, and insects. By decimating the ash population, the beetles are also destabilizing local ecosystems, allowing other invasive species, such as buckthorn, to take over.
Fighting back against the emerald ash beetle is everyone’s responsibility. We all need to be vigilant and look for signs of emerald ash borer activity in your ash trees. If you suspect you have emerald ash borers on your property, you need to immediately contact a reputable tree service company, like Martin’s Tree Service, for professional advice. We will assess the situation, make recommendations and safely remove any trees that are infected or have died.
Steve Martin
