The emerald ash borer (EAB), Agrilus planipennis Fairmaire, a non-native invasive insect pest of Asian origin, is presently infesting large numbers of ash trees in Ontario and Québec and could easily spread to adjacent provinces.  EAB infests trees for 2 or 3 years before outward signs of its presence. Such visual signs include woodpecker damage, epicormic shoots, and cracks with galleries under the bark. By the time these signs are visible control treatments may be ineffective in saving the trees, many of which are high-value urban specimens. Visual surveys are largely ineffective at detection during the initial stages of the outbreak. Similarly, indirect methods of EAB detection, such as trapping, are potentially ineffective in low density  populations. However, locating EAB populations early, when densities are still low, is critical because it allows more time and more options for managing the outbreak.

Researchers at the Great Lakes Forestry Centre have recently developed a branch sampling method that is proving to be highly effective at early detection of low-density EAB infestations. The method is presently being refined to increase detectability while improving efficiency of sampling. Several communities in southern Ontario are presently testing the draft protocol. The goal is to aid urban forest managers in managing EAB infestations, providing an opportunity for applying measures to control an outbreak during the time when trees display no outward symptoms. Costs and benefits of this sampling method are being compared with other sampling options, such as trapping and visual surveys, to determine which is most effective and efficient. Details of the method, which may also be applicable to other wood boring insects, are expected to be published in the coming months.