What’s next with the beetle in B.C.?

After a period of exponential growth, and then a slowdown, a big question lingers about the beetle situation in British Columbia—what’s coming next?

By Jim Stirling

The beetle watch in the forests of the British Columbia Interior is at a critical stage.

After a period of sustained and exponential growth, the rate of spread seems to have reached a hiatus in the last few months. The question now is, what’s next? The brief slowdown might reflect that a peak has been reached. But the opposite can just as easily be the case with beetle population numbers merely pausing for a new surge in growth. Experience with the mountain pine beetle epidemic taught that growth in the infestation rate was irreversible once it reached a certain critical point.

Most tree species native to the forests of B.C. have at least one forest beetle or pest with which to contend. The mountain pine beetle has removed much of B.C.’s adult pine population and many younger trees in Crown forests. The latest growth spurt in beetle numbers infesting other commercial species has been identified in spruce beetle populations, in Douglas fir bark beetles and Western balsam bark beetle numbers.

Beetle numbers can increase dramatically under suitable climatic and ground conditions, and quickly put otherwise healthy tree populations under stress.

Interpretation of B.C. government air and ground data shows about 7,631 hectares of forest land in the province was impacted by the spruce beetle in 2013. Seven years later, in 2020, the comparable figure had mushroomed to more than 500,000 hectares. During that relatively short time, the spruce beetle outbreak had become the most significant in B.C. since the 1980s.

“The spruce beetle is being closely monitored by the province,” reported the Ministry of Forests, Lands, Natural Resource Operations and Rural Development to the Logging & Sawmilling Journal in a recent statement. “Although the attack area decreased last year in the main outbreak area of Omineca (in north central B.C.), the area across the province is still holding steady.”

The ministry noted spruce beetles are a natural part of the historical disturbance pattern in spruce ecosystems: they can even help drive diversification within the ecosystem. “It is difficult to predict exactly where these outbreaks will occur and how large they will become. This is why our monitoring program is so important each year and why our focus is on sharing information and working with stakeholders when populations increase and attack standing healthy trees.”

The boost in spruce, Douglas fir and balsam beetle populations in B.C. is a shared phenomenon. It follows a now familiar pattern of events and circumstances that have helped rewrite B.C.s recent forest history. The warming and more erratic climate patterns is a recurring theme within them. The reality underpins the mountain pine beetle epidemic which the B.C. forests ministry estimates destroyed a staggering 18 million hectares of provincial forest land.

If that wasn’t a devastating enough toll on tomorrow’s forests, there was a punctuation to be added. In 2017 and 2018, the B.C. Interior experienced its worst two years of lands lost to wild fires since records began. In 2018, a provincial record of 2,117 forest fires consumed 1,354,284 hectares, eclipsing the previous year’s forest fire season record. The 2017 forest fire season was the worst on record for the central interior region. A provincial state of emergency was declared and lasted from July 7 to September 17. This past summer’s wild fires also took their toll—through to Sept. 1, the BC Wildfire Service responded to 1,562 wildfires that had burned more than 865,000 hectares.

The net result of those natural disasters has been an immediate shortage of fibre, especially that most suitable for the production of commodity lumber, and a proportional increase in costs. Other factors including continuing industry consolidation and reorganization—along with the imposition of contested duties on Canadian lumber entering the U.S. market—have compounded the B.C. forest industry’s woes. All that makes what happens in the near term with beetle populations additionally critical.

The B.C. Ministry of Forests has adopted initiatives to coordinate its response to the growth of beetle populations in the province. In the summer of 2020, Diane Nicholls, the provincial chief forester, presented updated guidelines for forest managers directing harvesting operations on land impacted by growth in beetle populations. “In stating my expectations regarding relative harvesting priority, I have carefully weighed the loss of short term salvage opportunities with the need to maintain future harvest opportunities and non-timber values provided by our forests,” she explained by way of context.

Essentially, she continued, the priority stands for harvesting should contain dead, dying and damaged timber, with the priority to those stands with greater than 50 per cent mortality.

“There’s a significant number of live trees in the understory of a spruce stand,” explained John Pousette, director of the Provincial Bark Beetle Response, whose duties include coordinating provincial response efforts to the beetle threats. “We want to make sure we’re prioritizing the stands as the most dead trees and not necessarily taking those stands that will re-build and recover,” he said.

Pousette added that clearcutting is no longer the only answer to mitigating a beetle infestation.

Beetle mitigation techniques are also being prescribed and applied on a micro scale in the region. For example, the city of Prince George and the provincial government teamed up in efforts to help reduce the spread of the spruce beetle within city boundaries. Pouches containing an anti-aggregate pheromone were attached to healthy spruce trees to discourage other beetles from infecting the tree. Trap trees containing spruce beetles were also used and burned in the Prince George area as part of forest fire prevention strategies around the city’s periphery.

But the next step to be played out on the regional stage will most likely depend on how and where beetle numbers trend after the beetle flights in the summers of 2021 and 2022.