After a decade long fight, the number of mountain pine beetles and newly attacked trees found in the eastern Rockies has dropped dramatically.
Alberta Sustainable Resource Development found roughly 100 beetle-attacked trees in Kananaskis Country last year, compared to 15,000 trees in 2009-2010 and 30,000 trees in 2008-2009, according to SRD forest health officer Brad Jones.
“It was slowly coming and the numbers declined quite a bit. We have half the number of trees across the area that we found in 2009 and 2010, but the number, the sharpness of the decrease, was really surprising,” Jones said on April 11, adding SRD officials did not expect that sharp drop.
The number of beetles and beetle-killed trees has been declining since numbers peaked in 2008-2009, and cold weather in the shoulder seasons – a time when the beetles, which produce a natural anti-freeze, are most susceptible to sub-zero temperatures – helped to reduce the populations.
The rice-sized beetles first showed up in large numbers in the Bow Valley in 2000 and 2001 as part of flights from large beetle-attacked areas in B.C. The beetles then appeared in the Willmore wilderness area, followed by large in-flights in 2006 and 2009, Jones said.
Large beetle infestations also occurred in northern Alberta near Grand Prairie.
Since the beetle-control program began, Jones said, SRD has spent about $250 million.
However, he added it was money well spent given the potential long-term effects of not undertaking the beetle control program, including watershed degradation and increased risk of forest fires.
“The biggest effect here would be watershed issues in the Elbow and the Bow (rivers) and forest fires, of course,” he said.
Surveys will be conducted to measure the over-winter mortality and to establish a sense of the current beetle population. These surveys, which will begin in May, will occur at eight locations in Kananaskis Country.
The aerial survey program, planned for August, will be reduced. However, a bait program will be used to monitor beetles coming into Alberta from B.C. and any spikes in the populations locally.
Bait stations will be set up at approximately 50 sites from the Ghost to Castle area, according to SRD.
In Canmore, SRD stated the report-a-tree program only identified four trees that had to be removed.
Meanwhile, Jones said, a phenomena known as red belt that causes large swaths of pine trees to turn rust-brown or red is caused by cold nights and warm days in late winter/early spring, not pine beetles. Trees affected by red belt normally recover.
