By Rose Sanchez
Alberta
Although officials believe a significant number of mountain pine beetles died through the winter and spring months, there is still concern about the threat of an in-flight of beetles this summer, especially in the southwestern corridor of the province.

Provincial officials released their findings from beetle surveys completed through May. For the Oldman River/Crowsnest Pass area they found beetle survival was low and there is a “low probability of local beetle production and spread. However, there is an extremely high probability of in-flights this summer.”

The area will be closely monitored to assess risk to the large volume of susceptible, connected pine as there is a still a large beetle population in southeastern British Columbia forests.

“It’s a bit of a war we’re carrying on with the Mountain Pine Beetle,” said Mel Knight, minister of Alberta Sustainable Resource Development (SRD).

Throughout the province 1,266 trees were sampled from 229 sites, said Erica Lee-Samis, senior forest health officer with SRD. The samples are cut and the number of pine beetle larvae that survived the winter and spring counted. Based on those numbers, provincial officials can determine how many beetles infested trees the previous fall, and how many may be on the move later this summer.

Overall in the province, a large number of beetles did not survive the winter and spring, although there are some hot spots in northern Alberta and the western border of the province.

“The survival rate was much greater last year than what we see here,” said Knight, adding the beetle numbers decreased from the previous year.

While he does credit the work of officials in removing infested trees and trees at risk of infection, Knight said the weather was a key factor.

“Mother Nature played the largest role in this particular story we’re bringing you today (July 7),” he added.

A cold snap last fall brought temperatures of minus 30 degrees which lasted a number of days. That killed off some of the beetles, but more likely most of the kill-off happened in the spring. Knight explained the beetles develop an “antifreeze” through the winter in order to survive. When warm weather hit in early spring, the beetles shed that antifreeze and then the temperatures dropped again, leaving the beetles vulnerable to that cold snap.

“I would suggest that’s the weather event that impacted them, at least this year,” said Knight.

Although numbers are trending downward, fighting the mountain pine beetle is a long-term battle. Knight said work will have to be done for at least the next two decades before the number of beetles is back to more historic figures for the province.

The government will continue to work to minimize the beetles’ spread through single-tree removals, stand-level harvests and controlled fires. The objectives are to minimize the spread of the beetles north and south along the eastern slopes to protect watersheds in the region and to prevent beetles from spreading east into the boreal forest.

More information about mountain pine beetle is available online at: www.mpb.alberta.ca.