Wood-eating budworm puzzles B.C. coastal forestry scientists

Budworm devastates forests in B.C. Interior, but mysteriously inactive on southern Vancouver Island

Research technician Jesse Simpson displays some Western spruce budworms at the Pacific Forestry Centre in Saanich. Simpson studies the worms

Research technician Jesse Simpson displays some Western spruce budworms at the Pacific Forestry Centre in Saanich. Simpson studies the worms

Forestry scientists are working to find out why a devastating tree predator from the B.C. Interior and Alberta is relatively harmless on the South Island.

The Western spruce budworm is capable of great defoliation and has a lengthy criminal record that should make Douglas fir trees itch uncomfortably in their presence.

“One thing we are looking at is why the budworm, which loves Douglas fir trees, is relatively dormant in our climate,” said forestry centre research scientist Brian Van Hezewijk.

“We know they were quite prominent here in the early part of the century.”

The budworm is on record for killing large swaths of canopy in 1909 and 1929 from Sooke to Saanich.

But its random patterns of attack, especially in the South Island where it was once active, has Pacific Forestry Centre researchers looking for a logical answer.

“It’s normal for it to have a bumper season every 30 to 40 years, but we’ve had nothing here since 1929,” Van Hezewijk said. “Nature has figured out a solution to this problem and we’re trying to find that out.”

A native species, the Western spruce budworm is a natural defoliator of trees and is healthy in Merritt, Lilloet and the Cariboo and Okanagan regions.

In Alberta, the tiny worms took down 36,771 hectares in 2006 and 142,832 hectares in 2007. Across B.C., the budworm has ruined approximately 1,598,500 hectares of trees between 1916 to 2002.

There are likely a few contributors to the neutralized bugs, but one leading theory and area of study is the effect of earwigs on the worm population.

An invasive species, earwigs came to the West Coast around 1919, Van Hezewijk believes.

On Vancouver Island, earwigs are prolific predators of budworm larva.

“Earwigs do reside in the interior, but perhaps it’s too cold or dry for them, we’re not sure,” he said.

Another predator that’s happy to lunch on the Western spruce larva is the parasitic wasp, which is also used to prey on gypsy moth eggs in the B.C. Interior.

In the meantime, the province has a regular spraying program that it will likely continue to limit the spread of the Western spruce budworm in affected areas each summer.

reporter@saanichnews.com

 

 

Just Posted

BC Housing has brought in sanitation trailers to the former Mount Tolmie Hospital site so its current residents can access clean water, showers, sinks and toilets after a collapsed sewer pipe impacted water service to the building. (Google Streetview)
Mount Tolmie Hospital homelessness shelter using sanitation trailers after pipe collapse

Travelodge shelter residents faced intermittent hot water supply in late May, early June

Numerous Esquimalt residents can now build a detached accessory suite of up to 65 square metres in their backyard. (Township of Esquimalt)
Backyard suites now legal for some Esquimalt properties

One unit of up to 65 square metres now permitted for eligible residents

COVID-19 exposures have been reported at Colquitz Middle School and Tillicum Elementary School, both on June 14. (AP Photo/Nam Y. Huh, File)
Two Saanich schools report COVID-19 exposures

Exposures reported at Colquitz Middle School and Tillicum Elementary School

An eastern cottontail rabbit on the UVic campus. (Evert Lindquist/News Staff)
Wild rabbits persist at the University of Victoria

Feral rabbits are still absent, but another non-native species has arrived on campus

An old growth cedar stands in a cut-block within the Caycuse Valley. More than 100 prominent Canadians, have signed an open letter calling for the immediate protection of all remaining old-growth forests in B.C. (Submitted)
Brian Mulroney and Greta Thunberg among 100 celebrities pushing to save B.C. old growth

List includes Indigenous leaders, scientists, authors, Oscar winners

People line up to get their COVID-19 vaccine at a vaccination centre, Thursday, June 10, 2021 in Montreal. THE CANADIAN PRESS/Ryan Remiorz
Vaccines, low COVID case counts increase Father’s Day hope, but risk is still there

Expert says people will have to do their own risk calculus before popping in on Papa

(Black Press Media file photo)
POLL: When was the last time you visited the mainland?

The films are again lighting the screens at local theatres, the wine… Continue reading

Anyone with information on any of these individuals is asked to call 1-800-222-TIPS (8477) or visit the website victoriacrimestoppers.ca for more information.
Greater Victoria Crime Stoppers wanted list for the week of June 15

Greater Victoria Crime Stoppers is seeking the public’s help in locating the… Continue reading

The pilot of this single-engine propeller plane was unhurt after crash-landing in a Como Road orchard Friday, June 18. Photo: Laurie Tritschler
Plane crash lands into Grand Forks orchard, pilot injured

RCMP have secured the crash site, pending investigation by Transport Canada

A tenant walks in front of her home on Boundary Road on Friday, June 18, 2021 after it was destroyed by fire the night before in Chilliwack. (Jenna Hauck/ Chilliwack Progress)
Family homeless after fire rips through Chilliwack house

Turtle rescued, no one seriously hurt following Boundary Road fire in Chilliwack

Wild rabbits are all over Chilliwack, but people often think they’re someone’s lost pet and try to ‘save’ them. But the owner of Chilliwack’s Reptile Room says good intentions can have bad consequences for wild animals. (Photo by THE CANADIAN PRESS)
Owner of Chilliwack’s Reptile Room asks people to leave wild animals in the wild

Amber Quiring says people who think they’re helping are actually doing more harm than good

Syringes prepared with Pfizer's COVID-19 vaccine are seen at a vaccination site in Long Beach, Calif., Friday, March 5, 2021. (AP Photo/Jae C. Hong)
Vaccine first doses now available for walk-ins on Vancouver Island

People aged 18+ can walk in for their first COVID-19 vaccine

Photos displayed at a vigil for former Nanaimo outreach worker Amy Watts, whose body was found June 3 and whose death RCMP are investigating as a homicide. (News Bulletin photo)
‘We need to do better,’ says mother of woman killed in Nanaimo

Vigil held for former outreach worker Amy Watts, whose body was found downtown June 3

Most Read