A forestry work crew uses a chipper to clean up cut wood as part of a fuel modification and pine beetle project in West Kelowna.

Working to keep pine beetle infestation at bay

The roar of a chainsaw sounds much more final than a tiny beetle killing a mature pine tree—but the effect is the same.

The roar of a chainsaw sounds much more final than a tiny beetle killing a mature pine tree—but the effect is the same.

And both will continue to fall the Central Okanagan’s native pine trees for the foreseeable future, according to authorities around the region.

Blair Stewart, the City of Kelowna’s urban forest technician, predicts local trees will be hard hit this year, despite the long, late, cool spring which could delay the first flight of mountain pine beetles.

In fact, there could be some bad years ahead as far as the infestation of beetles is concerned, he believes.

And with the province not providing any financial assistance this year, municipalities are on their own in trying to deal with it, he added.

Fortunately, Stewart said Kelowna is in a better situation than some, with natural breaks provided by Okanagan Lake and grasslands on some of its boundaries that help prevent beetle outbreaks and protect the city from fire once trees die from beetle infestation and become tinder dry.

While Stewart has seen massive majestic old pines in places like Knox Mountain Park killed by the mountain pine and western pine beetles, he remains hopeful some of the old pine trees in the city’s landscape can be saved.

Kelowna has been very proactive in removing infested trees from city-owned land before the current year’s flight of beetles has a chance to exit, infesting nearby live trees.

Within the next half dozen years, it’s expected that the current high cycle of pine beetles in this province will end, simply due to a lack of remaining pine trees for them to complete their life cycle in, Stewart noted.

Nick Arkle, a partner in Gorman Brothers Lumber in West Kelowna, says his staff are now noticing pine beetle damage where there has never been any in the past—even in areas where they thought the trees might be safe because of elevation or buffer zones around.

“It’s lucky we have a multi-species forest. Much of what is visible on the hills around the valley is predominantly Douglas fir, so it won’t be as impacted,” he commented.

Stacey Harding, parks supervisor for the District of West Kelowna, says they’ve already completed 19 projects this year in parks and district-owned land, removing beetle infested pines.

Infestation on the Westside has been spotty and random, rather than moving in like a wave, as had been expected, noted Harding.

Removal of beetle-infested wood is just one component of the district’s wildfire fuel reduction program, for which they still have some funds from a Union of B.C. Municipalities grant, but no private land can be included, he said.

The district’s west and northern boundaries are where the most pressure from the infestation is coming from, so work is being done in the Rose Valley area, Mount Boucherie and the boundaries of Glen Canyon, said Harding.

Surrounding municipalities should be glad the district has been proactive about acquiring grant money to do this work, because the beetle doesn’t recognize political boundaries, he noted.

He also commended the public for staying clear and being respectful of workers in parks and on public land.

The regional district is doing work in Glen Canyon Regional Park adjacent to downtown West Kelowna, and is working on plans for Rose Valley and Upper Glen Canyon Regional Parks, with the help of a fuel management grant from the UBCM.

Work has already been done in Mission Creek and Glen Canyon Regional Parks, according to Bruce Smith, spokesman for the Central Okanagan Regional District.

Mountain pine beetle attacks all species of pine trees, but western pine beetle only attacks ponderosa pine.

Following a ‘flight’ in early summer, the beetles attack pines nearby, depending on wind conditions, burrowing under the bark and interrupting the flow of sap up the tree.

By emitting an aggregation pheromone, they will work together to mass attack a tree and overcome its natural defence of ‘pitching out’ the invaders with a gob of pitch, visible on the outside bark of the tree.

That pitch tube is an indicator of trees which have been invaded by the beetle, even if the trees haven’t yet turned red and died.

A blue stain fungus carried by the beetle is partly to blame for the tree’s death, which occurs within a year of infestation.

One way to combat an infestation is use of a verbenone pouch containing an anti-aggregation pheromone, that tells flying beetles this tree is already full and there’s no room for more.

Forestry consultant Don Fowler says the best time to nail a pouch to your tree is prior to the first flight of the year, likely in early July.

He emphasizes the most important thing property owners can do is identify trees that have been attacked and remove them before summer, and properly dispose of them to prevent the spread of beetles.

There is a cost to deposit tree trunks more than 20 centimetres in diameter, and loads of tree debris of more than 250 kilograms in weight at the Glenmore Landfill.

But it’s not always possible to burn infested trees, and by disposing of them on the property or elsewhere, the beetles will fly and infest new trees.

All property owners are urged to remove and properly dispose of infested trees to help prevent spread of the beetle. Once dead, those also present a safety hazard, noted Stewart.

For more beetle information, go to the city’s website: www.kelowna.ca. To learn more about Firesmart guidelines, see www.pep.bc.ca/hazard_preparedness/FireSmart.

judiesteeves@kelownacapnews.com