Beetle invasion threatens forests from coast to coast

Billions of tree-munching beetles rained on hayfields, bogs and forests here six years ago, tiny paratroopers riding strong winds and a warming climate to a new front in the age-old struggle between parasite and pine.

Here was virgin ground for the pests, and easy pickings.

After the Tic Tac-size beetles survived three of north-central Alberta’s now-milder winters and then caught a still-larger wave of reinforcements riding 300 miles on summer winds from British Columbia, scientists knew the game had changed.