The pine beetle is a well-known pest, not an exotic import, but no effective means has been found to stop it. The beetles swarm up trees in large numbers, killing them by boring through the bark, sapping their nutrients and emitting a damaging blue fungus. Cold winters and forest fires normally keep the beetle populations in check. Some forest scientists trace the current outbreak to 1994, when provincial-government foresters, fearing the ire of greens, failed to eradicate a small infestation in a provincial park by cutting and burning.

The infestation is gathering pace. Wafted eastwards by strong winds, in 2002 the beastie made its debut in northern Alberta and further south in the national parks of Jasper, Banff and Kananaskis on the eastern slopes of the Rocky Mountains. It has advanced 400 kilometres (250 miles) across the province to Slave Lake. The beetle is now established in Alberta, despite vigorous cutting and burning.