...continued from Part 1
“Even the chief forester has given warning in her recent guidance documents to the forest industry that we should be doing partial cutting, and yet we have not seen a single block that isn’t hundreds of hectares of moonscape.”
Salvage logging for spruce beetle continues in the Anzac valley even though the area attacked by spruce beetle in the Omineca region, which includes the valley, dropped by almost 100,000 hectares from 2017 to 2018, according to figures provided by the B.C. forests ministry.
Province-wide, spruce beetle-attacked areas fell by 160,000 hectares over the same one-year period, according to the ministry, which said it is too early to determine if the outbreak is declining. Data for 2019 will be available in November.
Rea also points to the recent United Nations’ Global Assessment Report on Biodiversity and Ecosystem Services, which examines the ecosystem services provided by healthy forests, including water and carbon sequestration.
“They were basically pleading with communities around the world to start thinking about ways of doing things differently,” he notes.
“They said what we’ve been doing over the last several decades doesn’t appear to be working. The climate is changing. We’re losing biodiversity … This isn’t just stuff that’s happening on palm oil plantations in Indonesia. This is happening in our own backyard. And we all have to pitch in and figure this thing out.”
Even moose populations are in sharp decline in northern B.C., Rea points out.
“Nobody knows why. But the current working hypothesis proposed by government officials is that it has to do with landscape (habitat) change. Nobody ever suspected that we could possibly hemorrhage 70 per cent of our moose population in northern British Columbia in [the last] 15 or 20 years.”Forests left alone recover faster from spruce beetle
Spruce beetles are drawn to windfall like wasps are to sugar water, favouring the downed wood over anything green and standing. Falling a few older spruce has long been a strategy to temper beetle outbreaks.
Once a year, in summer, spruce beetles fly in huge swarms. Most travel only a few hundred metres but a “substantial number” fly up to several kilometres away, according to Six. If beetles make their way into a wind column, they are capable of landing tens or hundreds of kilometres away, she says.
“They fly. They mass attack. They lay their eggs. And then you don’t see them flying again for another year because it takes that long for the larvae to develop to new adults.”
Six, whose research also focuses on how bark beetles affect the ability of forests to adapt to climate change, says trees that survive spruce and pine beetle outbreaks may be genetically more resistant to both beetles and a changing climate.
“These outbreaks likely act as major natural selection events,” says Six, the co-author of a peer-reviewed paper, “Are Survivors Different?” that examines why some mature trees survived a mountain pine beetle eruption.
“That has shaped resistance in the past … Cutting out all trees, including survivors, removes any adaptation that may be occurring just at the time we need it most.”
Scientists have studied spruce beetle outbreaks in U.S. national forests, comparing areas that were left alone to areas that were logged, said Six.
“And the ones that basically were left alone are recovering much faster.”
Thousands of dollars are now being spent on “snag management” across U.S. western states in order to save bird populations whose habitat has been destroyed by clear-cut logging, Six points out.
Snags — dead or dying standing trees, often missing their tops — are used by woodpeckers and other birds for nesting.
A recent survey of more than 500 bird species in Canada and the U.S. found that more than three billion birds have been lost since 1970.
“We’re losing birds so fast we’ve got to get some of these things back,” Six says.
The U.S. forest service is now finding ways to damage big trees so they will rot faster and provide nesting habitat and insect food sources eliminated by clear-cut logging.
“And as a wonderful side effect of getting back your bird species you help manage your insect pests,” Six says. Leaving trees helps wildlife and future timber supply
Rea says the swath of red across interior forests attacked by the spruce beetle creates the impression that the forest is dead, especially from the air.
“But as soon as you get under that spruce crown there’s a lot of life in many of these forest stands … I don’t think we should say, ‘the overstory trees are dead, we need to clear the whole thing,’ ” Rea says.
“Every single tree that you can leave standing, even it it’s a little teeny willow or a subapline fir, if it’s got leaves on it or it’s got needles on it and it can soak up carbon, let it do that.”
Instead of piling up wood waste from clear-cutting and burning it, contributing to greenhouse gas emissions, leaving it on the ground would create habitat for wildlife such as voles, mice, shrews and salamanders, which in turn feed other wildlife that themselves perform important ecosystem services, Rea says.
Leaving behind more trees not only retains biodiversity and ecosystem services but it also nurtures secondary stand structure that can help meet mid-term timber supply needs, Rea says.
“We’re knocking down a lot of trees that end up in burn piles and, if left standing, in 20 or 30 years could be on their way to the sawmill.” https://thenarwhal.ca/hundreds-of-hectares-of-moonscape-b-c-spruce-beetle-infestation-used-to-accelerate-clear-cuts/