The emerald ash borer (EAB) is a metallic green beetle, about a centimetre in length. In its native Asia, the beetle attacks already weakened and stressed ash trees, but in North America it kills healthy ash trees. Once established, EAB kills almost all of the ash trees in an area. Since more than a quarter of Saskatchewan's urban trees are varieties of ash, the beetle poses a serious – and potentially costly – threat as dead trees must be removed and replaced.
How EAB Spreads
The beetles live and breed in ash wood, so people transporting infested firewood or wood products is the most common way that EAB is spread. The beetle likely arrived in North America from Asia in wood packaging materials or pallets, and was first detected in the Detroit/Windsor area in 2002. Since then, it has spread throughout the eastern U.S. and Canada. In 2017, the emerald ash borer was found in Winnipeg.
Prevention and Management
Invasive pests, including EAB, are federally regulated, with monitoring and control effects led by the Canadian Food Inspection Agency (CFIA). The Government of Saskatchewan has also put regulatory controls in place to support the CFIA's efforts. EAB has been designated as a pest in Saskatchewan to prevent infested wood or seedlings from entering the province.
The key to managing the EAB threat is an integrated approach that includes prevention, early detection and removal of infested trees. Symptoms include branches dying, D-shaped holes on the main trunk and larger branches, and root sprouts at the base of the dying tree. Unfortunately, EAB can be very difficult to detect. By the time trees show symptoms, they may have been infested for up to five years, with EAB populations already well established.
What can I do?
You can help manage the EAB threat in two ways:
- Do not transport ash firewood and wood products from an infested area into a non-infested area. It is illegal.
- If you suspect your tree has EAB, report it to your local municipal authority or the Ministry of Environment (1-800-567-4224).