Alberta’s mountain pine beetle population has fallen for the fourth year running, says the province.
Beetle populations have fallen 94 per cent from their 2019 peak as widespread and continued cold has taken a toll on the pests that have infected nearly six million acres of Alberta forest. In the most severely affected areas, beetles killed all the pine trees.
“I am pleased to see that our approach to controlling the spread of mountain pine beetles and favourable weather trends are having such a positive impact in many areas around the province, and we will continue to protect our forests for future generations,” Forestry, Parks and Tourism Minister Todd Loewen in a statement on Tuesday announcing the good news.
Operations continue to manage sites of concern. Aerial surveys of nearly 17 million acres of forest in areas where pine beetles are active were completed in August.
Pine beetles kill trees by producing a blue-stain fungi that clogs and destroys the conductive tissue of an affected tree. More than 13 million acres of pine trees valued at $11 billion are vulnerable to the beetles.
“We’ve absolutely seen a reduction in the number of trees that are being hit by mountain pine beetle,” said Sundre Forest Products forestry superintendent Tom Daniels.
The evidence can be found in the roughly 70 dispersal baits that the company sets up to attract mountain pine beetles and get a read on how prevalent they are and whether there has been another flight of the bugs.
“We’ll put them out in July and then we’ll go back in August and then check them again at the end of the year,” he said.
“If the beetles are flying, they’ll get attracted to that pheromone that we put on the trees and then we’ll see evidence of that flight.”
If they find evidence of pine beetle flights they can focus on that area and look for other infected trees.
“Based on that, we’re not seeing any real hits of beetle. We’ll get a few hits on a couple of trees, but nothing like a mass attack.
“We’re always going to see those low-level hits because mountain pine beetle is endemic to the forest. It’s just when it reaches those epidemic populations that it causes the problems.”
That was the case about 16 years ago when pine beetle showed up in Alberta in huge numbers.
“Back in ’06, when things really started to blow up, there were really massive flights coming in from British Columbia.”
The risk is not over, warns the province.
“While a sharp, widespread decline in mountain pine beetle populations is welcome news for the province, the threat of resurgence still remains in some areas,” says the government.
“Continued population pressure from Banff National Park, coupled with recent relatively mild winters, men that the Bow Valley, Kananskis and Crowsnest Pass areas remain a priority for continued management and control.”
Daniels agrees the war is not over.
“It would be awesome if I could say problem solved, but that is not the case.”
In B.C., a cold winter knocked the pine beetle population back one year but numbers rebounded when conditions were better the following years.
“All it takes is a couple of good years and the population has the ability to rebound so quickly because of the growth potential of that population.
“It’s something we’re just going to have to keep an eye on just make sure we’re not seeing an increase in that population because of warmer weather.”
Alberta has had an advantage over B.C. because the province had time to take defensive measures. “We saw what happened in British Columbia and we were able to employ different strategies.
“Those strategies are important because we have so far been able to safeguard the rest of Canada. We’ve been able to contain the beetle to Alberta, not into Saskatchewan. If it starts to cross the border, it has the potential to go right across Canada.”
Since the late 1990s, pine beetles had infected at least 45 million acres of B.C. forest by 2012. As of 2017, about 60 per cent of the merchantable pine in B.C. — 750 million cubic metres — was lost, according to a Natural Resources Canada website.
Ken Fry, instructor at Olds College’s School of Life Science and Business, was at a forest pest conference this week where an Alberta government forestry expert provided an update.
“It is good news for Alberta forests,” said Fry in an email. “It is a testament to the hard work of the forest protection staff of the Ministry of Forestry, Parks and Tourism.
“The combination of wet periods in the summer, along with three successive severe cold spells and the aggressive detection and removal of infested trees by ground crews has contributed to the decline witnessed since 2019,” said Fry.
“What the future holds is uncertain but the reduction in (mountain pine beetle) numbers reduces the eastward march of the population, at least for the near term. As always, it depends on the weather and climate.”