magazine / ja03 / indepth
Canada's burning bush
Let it burn!
Why Canada's National Parks use fire to prevent fire
By Michael Bhardwaj
'Fighting fire with fire' is more than just an adage for Canada's national parks managers.
It is a matter of practice.
After years of believing wildfires were a destructive force that turned valuable land into smoldering ash, parks managers now view fire as essential to ecological processes.
"Fire was a problem 125 years ago because it destroyed forest and animals," says Stephen Woodley,
Parks Canada's chief of ecosystem science. "The key reason for having a warden service was to suppress
these fires." But Woodley says Parks Canada's perspective on wildfires has changed dramatically since the 1960s.
The shift was catalyzed by cutting-edge research which showed
that certain ecosystems, such as the prairie grasslands, were
just as dependent on fire as they were on wind, water and earth.
"Fire is an essential part of the ecosystem," says Woodley. "If
you take fire out of the equation, it increases the propensity
of fire."
Such was the case for Canada's northern forests where,
prior to the 1960s, fires were often fought regardless of how
remote or insignificant they were. Consequently, dead and decaying
junk from the canopy would slowly rot on the earth below, creating
layer upon layer of rotting organic matter. A wildfire would
begin with something as simple as a blast of lightning, a spark
from a campfire or a hidden ember burning in the bush. Backed
by strong winds and fed by layers of dry fuel, these blazes
would grow to epic proportions, raging through the canopy with
such heat and ferocity that trying to fight them was impossible.
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With the advent of the prescribed burn program, Parks Canada
has managed to beat back wildfire. Backed by years of research
and the latest computer models, which provide astonishingly
accurate predictions, wardens, planners and fire crews deliberately
set fires under a strict control regime to burn away excess
fuel loads that would otherwise be a hotbed for wildfire.
Banff National Park has been conducting prescribed burns for
the past 20 years. Starting in the spring, these fires help "preserve
the ecosystem by maintaining the representative vegetation and
wildlife, which are adapted to fire," says Ian Pengelly, a fire
and vegetation specialist at the park.
Before burning, Pengelly says a lot of effort is devoted to
researching when an area had fire: how intense and how far-reaching
they were. With the history in hand, a detailed burn plan is
set up, taking into consideration the amount of fuel on the
ground, the time of year and, most importantly, safety concerns.
On the day of the burn, weather conditions are carefully monitored
to ensure that wind direction and speed, humidity and temperature
create ideal conditions.
"We want to find a combination of weather conditions that will
give us the heat and intensity so that the fire will spread," says
Pengelly.
A constant in their plan is setting the fire within natural firebreaks,
such as rock walls, rivers or lakes and artificial breaks created
by thinning the surrounding forest and back-burning the under-story
to get rid of fuels that could spur the fire on. With these breaks
etched in, Park crews begin the burn — a fire at the park
is set within the perimeter of the established break — knowing
they have a safety net in place.
At Banff National Park, tree species such as the Lodgepole pine
depend on the heat of the flames to release the next generation's
seeds. These seeds germinate in the nutrient-rich soil after the
nests of acidic pine needles are gone from the understory. Fire
also helps to curb the rising infestation of the mountain pine beetle
that recently infected the edges of Banff's pine forests.
Despite the proven benefits of fire, the sound of Smokey the
Bear's baritone mantra still echoes from years past.
"People are afraid that fires would get out of control and
threaten houses and accommodations at the park," says Woodley. "People
are still coming to grips with the role of fire in the ecosystem."
Minimizing risk not only involves precision planning but also
talking to local communities about the pros and cons of fire.
Well before the burn, Pengelly says staff at the national park
tour through the community, notifying residents about the planned
burn, when it will happen and the risks involved. Residents
are advised to close their windows during the burning period,
and if anyone has breathing problems they are told to keep inhalers
close at hand or to leave the area temporarily.
Once the burn begins, daily announcements about the fire's
progress are made on local radio stations and in newspaper articles.
Keeping the community informed about what has been done, where
things stand and what to expect is a priority for the national
park.
It has been an uphill battle for Parks Canada to convince communities,
industry and even their own politicians about the benefit of
fire. Slowly but surely, opinions are shifting and attitudes
are changing towards understanding the positive impact fire
has on an environment.
After all, says Woodley, "Biodiversity does not exist in spite
of fire. It exists because of fire."
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