How a beetle outbreak may have caused two sawmill explosions in B.C.

t’s a bug the size of a grain of rice, but it has an appetite as big as British Columbia.

With a little help from climate change, the mountain pine beetle has killed or infected 8.7 million hectares of the province’s lodgepole pine forest since 2005. That’s an area almost three times the size of Vancouver Island.

If you’re looking for the cause of the sawmill explosions that killed four workers and injured dozens more in 2012, the beetle is a good place to start.

Don't blame the beetles

When the evergreen trees turned red, it was hard not to worry. The die-offs started in Alaska about 20 years ago, and soon conifers were perishing en masse across western North America. Life drained from millions of hectares of forest so quickly it was as if they had been abruptly unplugged, like a Christmas tree before bedtime.

The killers: tiny insects called bark beetles. Many people worried that the dead, dry trees would give birth to huge, damaging wildfires. To prevent infernos, some U.S. lawmakers pushed expensive, controversial policies to aggressively log beetle-damaged trees. “We are battling a huge insect epidemic that is destroying our forests” and creating “prime real estate for forest fires,” warned then-Representative John Salazar, a Democrat from Colorado, on the floor of the U.S. House of Representatives in 2006. To some casual observers, the prediction seemed to come true as blazes such as the 2012 High Park Fire near Fort Collins, Colorado, set records for hectares burned and homes destroyed.

But that fire, like others, burned green forest as well as beetle-killed trees. And now, a growing body of research—including a study published last week—is challenging the notion that beetle-killed forests are more vulnerable to severe fires than forests that have escaped infestation. The findings are highlighting the complex causes of western wildfires and raising new questions about policies that promote the removal of insect-damaged trees to reduce fire risks. Contrary to popular belief, says forest ecologist Thomas Veblen of the University of Colorado (CU), Boulder, the science suggests that “healthy forests [can] include fire, and bark beetles, and lots of dead trees.”


The devastating spread of the mountain pine beetle

When the mountain pine beetle began blazing a path across forests in British Columbia and Alberta, nobody could have imagined the extent of the damage to come. But as the insect devastated pine forests and disrupted communities, forest industries, recreational use, watersheds, and plant and wildlife habitats, the problem became disturbingly clear. Now, as the beetle creeps into the boreal forests of the Northwest Territories and Saskatchewan, with a real concern it may reach as far east as the Maritime provinces, researchers at the University of Alberta have responded to calls from government, industry, non-profit organizations and the general public to help conserve and protect an invaluable national resource at the heart of Canadian identity.


University of Alberta researcher studying pine beetle flight patterns

A University of Alberta biologist aims to get a step ahead of pine beetles with new research on the pesky insect’s flight patterns.

Maya Evenden, who has been studying mountain pine beetles for eight years, said the U of A is breaking into new territory by measuring flight capacity.

“When the beetle comes out of the tree as an adult, it has to fly to reproduce,” Evenden said.


Drought could reverse drop in bark beetle numbers

The amount of Nevada forest under assault from bark beetles and similar bugs dropped significantly last year, a promising trend experts said could be reversed in a big way should the current drought continue much longer.

All across the state, populations of tree-killing insects plummeted in 2013 from levels seen in 2012, a change revealed by aerial surveys, said Gene Phillips, forest health specialist for the Nevada Division of Forestry.

"These are some pretty dramatic decreases," Phillips said.