Ash trees throughout Canada are under threat, not from loggers or wildfires, but from a highly invasive and insidious predator. The emerald ash borer (EAB) has launched a massive invasion of Canada and if something isn’t done soon, it may be too late to save our beautiful trees.
What is the Emerald Ash Borer?
The EAB is a green jewel beetle native to northeast Asia that feeds on ash species. In its native regions, it does not cause any significant damage to indigenous trees. Outside its native range, however, it is a highly invasive and destructive species that is rapidly destroying ash trees native to northwest Europe and North America. The EAB is so destructive because its larvae feed on the cambial layer below the bark of the tree. This disrupts the flow of nutrients and water between the roots and the rest of the tree, and over time the tree dies. On average it takes about two years for this pest to kill a tree.
The EAB was first detected along the Canadian border near Windsor in 2002 and is now present in 75% of municipalities around the country. In the last 15 years, the EAB has killed an estimated 15 million ash trees in Canada. The loss of the ash from an ecosystem can be devastating for the region. It can lead to an increase in the number of invasive plants, change soil nutrients and composition, and affect the species that rely on the ash trees for their survival. But fortunately the government, municipalities, and homeowners are fighting back and there is hope on the horizon.
What is being done?
If left unchecked, the EAB will destroy almost 100% of Guelph’s ash trees. Like most municipalities around the country, the City of Guelph is implementing strategies to deal with the infestation to the cities trees. This includes monitoring, treatment, removal, and replacement. The City is also coordinating its EAB mitigation efforts with agencies such as the Canadian Food Inspection Agency, the Canadian Forest Service, the Ontario Ministry of Natural Resources, Grand River Conservation Authority, Wellington County and neighbouring municipalities.
Bio-control methods
The government, along with Natural Resources Canada, is investigating and testing a number of bio-control methods to try and solve the EAB problem. Bio-control is part of an integrated pest management strategy and has been used successfully in other industries, like agriculture, to control pests.
These methods include installing and monitoring of traps. The monitoring of these traps makes the control of EAB more cost-effective by allowing municipalities to identify and target the worst affected areas. Some of the traps are laced with a pheromone that attracts male EAB. Trapping the males can reduce the EAB population by making it harder for females to find mates.
Bio-control also includes the reduction of pest populations through the introduction of natural predators and enemies into the environment. The government is currently doing test releases of specially-bred parasitic wasps, and naturally occurring pathogenic fungi, in highly infected areas. The tiny wasps, that are native to China, pose no threat to humans. They do not sting people and only prey on the EAB. Although there is currently little chance of eliminating the EAB entirely, the government hopes to develop several proven methods for reducing and controlling the population.
What can you do?
This problem is not just the responsibility of the government and municipalities, residents and landowners all need to play their part. You need to be vigilant and look for signs of EAB activity on your property. Infected trees will slowly die and are at risk of falling over. If you suspect you have emerald ash borers in your trees, you need to immediately contact a reputable tree service company, like Martin’s Tree Service.
A professional arborist will help you assess the situation and make recommendations. Martin’s Tree Service will also safely remove any trees that are infected or have died.
Steve Martin
