Butternut canker: a well-established
exotic pest. Photo: CFS

Each exotic fungus species poses a new threat of disease to Canadian forests. To detect such pests, an early warning system based on DNA analysis of plants that are imported into Canada showing no symptoms of disease has been put in place.

This research project, which results from a collaboration between the Canadian Forest Service (CFS) of Natural Resources Canada and the Canadian Food Inspection Agency (CFIA), is designed to intercept exotic fungi before they become established in Canada. It targets live plant material such as cuttings, seeds, ornamental plants and bonsai.

Photo: CFS

Photo: CFS

Exotic fungi with the potential to harm Canadian forests were present in 87% of the sample lots analyzed. Of the 157 fungus species detected, 11 had moderate impact potential and 15 had low impact potential. However, none of the species posed an immediate threat to our forests.

Exotic fungi that are harmless in their country of origin can quickly become pathogens of our trees, which have no defence mechanisms against these new pests. Once established, it is difficult, and sometimes impossible, to eradicate them. This is the first system in the world designed to detect exotic pests on plants that appear to be perfectly healthy.

Useful link: Forest invasive alien species (FIAS)