By MARK HUME
Wednesday, November 9, 2005 Page A2 | Globe and Mail
VANCOUVER -- Using methods that seem designed to battle an invading army, government officials in British Columbia and Alberta have been burning forests along their shared border in an attempt to stop a massive infestation of pine beetles from spreading eastward.
But despite the extreme measures, which this fall included the destruction of about 5,000 trees in Willmore Wilderness Park, about 150 kilometres north of Jasper, the pine beetle has rapidly been making inroads into Alberta, jumping from B.C.'s lodgepole pine to the jack pine of the boreal forests.
The insect has been slipping through mountain passes from the Peace River country, in northern British Columbia, to the Bow Valley, west of Calgary.
With more than 3,500 infestation spots now identified east of the Rocky Mountains, which long served as a natural barrier to the insects, the way seems clear for an outbreak in the northern boreal forest, which reaches from British Columbia to Labrador.
Scientists say the beetle, which leaves valleys of dying, red trees in its wake, is spreading because global warming has reduced the winter cold snaps that used to kill off the insect.
The leading edge of the mountain pine beetle infestation moved into the Peace River district in 2002, where it is now well established, said Allan Carroll, a scientist with the federal Pacific Forestry Centre in Victoria.
"The bulk of the population has breached the Rocky Mountain barrier," Mr. Carroll said in an interview yesterday. "It comprises several thousand spot infestations, all of which have become reasonably well established and have been growing since their arrival. . . . It's quite worrisome because we have this large population sitting now adjacent to the most logical corridor into the boreal forest."
In Alberta, officials have deployed aerial surveys, ground patrols and rapid-response teams to cut and burn trees infested with mountain pine beetles. But Mr. Carroll said the insects are almost impossible to eradicate.
"We certainly have every reason to think we can slow it, but stopping it is difficult," he said. "Once it becomes established in a pine forest, it becomes a part of that ecosystem and can exist at extremely low levels, levels that we are pretty much unable to detect. It remains at background levels until conditions arise that allow it to erupt."
Some researchers warn that the pine beetle could spread through Canada's boreal forest and across North America.
"If mountain pine beetle is successful in colonizing jack pine, there is a continuous connection of suitable host species across the boreal forest, down the East Coast of the United States all the way to Texas. What we are describing here is a potential biogeographic event of continental scale with unknown, but potentially devastating, ecological consequences," researchers Jesse Logan, of the U.S. Forest Service, and James Powell, of Utah State University, said in a recent paper.
The scientists said the scale of the outbreak in B.C. is "truly astounding."
Across the Prairies, resource managers are taking note.
Rory McIntosh, forest insect and disease specialist with Saskatchewan Environment, said his province has been anticipating a possible pine beetle invasion for years. "We are very concerned about this. It's certainly a major item on the agenda at the provincial and national level."
In a few weeks, he said, signs will be going up on major highways along the border with Alberta, urging people not to import into Saskatchewan any wood with the bark still in place.
Mr. McIntosh said if an infested forest spot is detected "we would do an immediate cut-and-burn, and we'd cut 50 to 75 metres into the edge of the forest around that."
That's the kind of rapid response Alberta has been using - swooping down on wilderness valleys to cut and burn any infected trees they find.
In B.C., the outbreak covers more than seven million hectares and has cost the provincial economy an estimated $6-billion. In Alberta, more than two million hectares of pine forest are at risk along the eastern slopes of the Rockies, with an estimated commercial value of $23-billion.
