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The Register-Guard, Eugene, Oregon

September 21, 2002

Closer look inside wildfire shows that all is not black

The Associated Press

GRANTS PASS - When Biscuit - the nation's biggest wildfire this year - was
on its hind legs and roaring last July, anyone looking at the towering
plumes of smoke in Southwestern Oregon could only wonder how anything could
survive the inferno.

Now that most of the flames have cooled, however, a look at the nearly
500,000 acres within the containment lines reveals a landscape typical of
wildfire: More than half either did not burn, or burned at low intensity,
leaving mature trees green, standing, and better off.

"When a fire burns, unlike what is seen in cartoons, not every tree is
killed, not every plant is killed, not every acre is burned to nothing,"
said Eric Christiansen, fire behavior analyst on the elite federal
management team that stopped Biscuit from roaring into Oregon's Illinois

While the fire put the 17,000 people in the valley on evacuation alert as
it burned five cabins and threatened others, in the long run it maintained
the well-being of individual species and the forest as a whole, said Tom
Atzet, the U.S. Forest Service ecologist for southwestern Oregon.

"The worst thing that we could have is to be so enamored of our forests
that we eliminate the processes that change them," Atzet said.

Charred rings on old trees show fire returns to the area burned by Biscuit
every 70 years on average on the wetter west side and every 50 years on the
drier east side, said Atzet.

Just how that fire burns depends on the mix of weather, fuel and terrain,
said Christiansen.

A windy, hot dry day, combined with steep ravines filled with heavy brush,
downed logs, and tightly packed trees, means flames twice the height of the
timber and temperatures up to 2,000 degrees.

But you would hardly notice the fire that comes through sparse timber in
flat rocky ground on a cool humid day with little wind. Even patches of
grass survive.

Both those scenarios can be found on Biscuit. As conditions changed through
each day and across the landscape, the fire intensity changed, creating a
mosaic of different results.

A satellite map for assessing rehabilitation efforts showed 19 percent of
the Biscuit Fire area, about 95,000 acres, was unburned, and 41 percent,
about 205,000 acres, burned at low intensity, leaving green trees standing
and healthy while clearing out brush and small trees.

Only 15.7 percent, about 78,500 acres, burned at high intensity, leaving
little but ash and charcoal behind, and 22.6 percent, about 113,000 acres,
burned at moderate intensity.

A good place to see the phenomenon is Babyfoot Lake. The fire burned hot on
steep slopes around the lake, but at the shore, where the water cooled and
humidified the air and a towering cliff cut the wind, half the shoreline
did not burn. Centuries-old pine and Douglas fir stand as proof that fire
can't fully flex its muscles here.

The same phenomenon served to spare much of the vegetation along the
Illinois River, home to salmon and steelhead, said hydrologist Jon Brazier.

The Forest Service has yet to analyze just how past logging may have
affected fire behavior, an issue in the debate over how forests should be
managed to reduce vulnerability to wildfire.

But logging may not prove to be much of a factor.

There has been little cutting here since the 1980s, and the burn analysis
of the 1987 Silver Fire, which burned nearly 100,000 acres in the same
area, showed little difference between wilderness and areas that had been

At a cost of nearly $150 million, fighting Biscuit looks expensive. But
another way to look at it, Atzet said, would be to imagine Congress
appropriating $150 million to do prescribed burns restoring fire to its
proper place in the ecosystem.

"In an ecological sense, we just invested $150 million," Atzet said.

For example, the kalmiopsis bush, for which the Kalmiopsis Wilderness where
the fire started is named, depends on fire to kill the white fir that
competes with it for water, sunlight and nutrients, Atzet said.

The thin bark on white fir gives it less protection from fire than
ponderosa pine and Douglas fir, with thick bark. Surviving trees do better
than ever.

Dwarf mistletoe, a parasite that stunts Douglas fir, gets knocked back by
fire, said Ellen Goheen, a Forest Service plant pathologist.

"Mistletoe creates huge brooms in trees," she said. "Those brooms act as
wicks, taking ground fire to a crown fire."

Spaced out more widely by fire, trees are less susceptible to root
diseases, such as deadly Port Orford cedar root rot, which can be passed
root-to-root, she added. Heat kills the spores.

Darlingtonia - an insect-eating plant also known as cobra plant - will
probably expand their command of hillside bogs now that competing plants on
the edges have been killed, said Siskiyou ecologist Diane White.

Chemicals leaching out of the ashes can stimulate acorns to sprout into oak
trees, giving them a head start on pines and firs waiting for the spring.

Madrones will sprout from the bole - the underground connection between the
trunk and the roots - after the top of the tree is killed.

Knobcone pines not only need the heat of fire to open their cones, but
their seeds love the mineral soil exposed when fire burns off the duff -
needles and bark built up over the years.

"It's important that part of the system be burned at high severity," Atzet
(c) The Register-Guard, Eugene, Oregon

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