[pct-l] distressing info about section d

canoeman at qnet.com canoeman at qnet.com
Fri Nov 6 00:56:18 CST 2009


here is some info straight from the forest service fire zone inspection team
 the U.S. Forest Service scientists who have spent the last two weeks in 
the San Gabriel Mountains examining the effects of the Station fire are 
like forensic pathologists combing a crime scene. Except in this case, 
the patient is still alive. "We're more like doctors, and our patient is 
ill. We're trying to figure out how to make it better," said Roath, 
regional director of post-burn analysis and a 33-year Forest Service 
veteran.
Although the 45-member team's report will remain under wraps for some 
time, the preliminary findings are in: Don't pray for rain. Using 
sophisticated burn maps generated by satellite imagery and factoring in 
the breathtaking steepness of the now-denuded hillsides, the scientists 
warn that even moderate winter rain could trigger landslides and 
catastrophic debris flows capable of inundating many of the San 
Gabriels' 37 foothill communities. Beyond that, the scientists concluded 
that although 250 square miles of the Angeles National Forest burned, 
the trees and chaparral in the fire-adapted ecosystem will bounce back. 
However, much of the wildlife that makes its home in the 655,000-acre 
forest was killed or dislocated. Biologists say they found an unusually 
high number of large animals caught by the fast-moving fire. Teams have 
come across carcasses of bears, mountain lions, bobcats, coyotes and 
gray foxes, apparently unable to find escape routes. "Deer took a big 
hit," said Kevin Cooper, a wildlife biologist. The BAER team (for Burned 
Area Emergency Response) worked 14-hour days to complete its work, 
retreating each night to laptops at the "BAER Den," a Residence Inn 
conference room in Burbank. Specialists were on the ground in every part 
of the 160,000-acre burn area, measuring, photographing and testing. The 
team included soil scientists, hydrologists, archaeologists, botanists, 
wildlife experts and a hazardous materials crew. The fire peeled back a 
layer of cover to reveal unknown Native American oven sites, scores of 
illegal dumps and a stash of 50-gallon drums filled with an as-yet 
unidentified liquid. One day last week, Roath steered a white Forest 
Service SUV up the Angeles Crest Highway, which was closed to the public 
but nonetheless busy. Crews used graders to clear boulders, 
semi-tractor-trailers hauled debris and workers with chain saws cut 
trees that threatened to fall across traffic lanes. Overhead, 
helicopters carried water-dropping buckets or ferried dangling loads of 
replacement utility poles.
For the most part, the landscape was devoid of color. Gray-white ash has 
banked in places, like dandruff on the shoulders of the mountains. 
Roath, a soil scientist who began his Forest Service career on the 
Angeles, is still awed by the immense natural forces once marshaled to 
lift this mountain range that is still rising and settling. He noted 
that debris cones -- accumulated rock and sand at the bottom of sharply 
defined ridges -- are sprouting up everywhere, as though the mountains 
are shedding dead skin. The San Gabriel Mountains have the potential to 
unleash calamity under normal circumstances, without the overlay of fire 
to complicate things. They are mountains on the move; the rock is 
fractured and disintegrating. Roath said that as BAER team members 
collected their data, they could hear the rattling sound of mountains 
falling. "In some cases boulders are coming down from gravity alone. 
They don't need rain," Roath said. Vegetation plays a critical role in 
shoring up hillsides. When rains come, the drops hit the plant canopy 
first, which slows the water and distributes it more evenly into the 
soil. Absent vegetation, rain pounds down and washes away topsoil, sand, 
small rocks and burned plant material.
Thus begins a process that scientists call "entraining" -- the terrible 
freight of broken mountainside that gathers energy as it roars 
inexorably downhill. Storms cause sediment to back up in ravines already 
loaded with fire debris. The flow bulges and spreads, picking up larger 
stones, then boulders. It gains speed as it descends, blowing obstacles 
out of its way. That debris, too, joins the train. As highway culverts 
become full, the entire river of rock flows over the roadway, collapsing 
it. The broken asphalt then becomes a passenger on the cascading 
wreckage. Trees, automobiles and houses scarcely slow the torrent. 
"Debris flows are a little hard to control," said Sue Cannon, a debris 
flow expert with the U.S. Geological Survey in Denver, adding that the 
San Gabriels present a "classic setting for major debris flow." Along 
the upper Big Tujunga Road, fire appeared to have followed the drainage, 
burning trees that straddled the creek, leaving "a pretty well-toasted 
riparian area," said Jan Beyers, a Forest Service plant ecologist. 
Cooper, the wildlife biologist, noted that the Station fire took out 
trees along the streams, such as white alder. Large trees are like 
straws, sucking water from rivers and streams, and in their absence, he 
said, there has been a measurable increase in stream levels in the 
Angeles National Forest. Elsewhere along the road, a row of roasted pine 
trees offered clues to the fire's behavior. Their brown needles point 
sideways, petrified at an acute angle, like a heavily gelled hairdo. 
This, the scientists explained, is an example of "fire freeze," the 
result of a hot wind blasting through, wringing the last drop of 
moisture out of the tree. Where some see withered plants and scoured 
hillsides, Beyers sees decades of patient aspiration come to fruition -- 
the "shooters and seeders." Trees that have lost limbs to fire will grow 
new, sturdier arms. Plants that have been annually depositing seeds in 
subterranean "seed banks" will be rewarded with young growth rising out 
of soil rejuvenated with nitrogen-bearing nutrients. "There are seeds in 
the soil here that have been waiting decades for this chance," she said 
wistfully. Indeed, for some growing things, fire is a bonanza. Certain 
species of conifers require heat to release seeds from their tightly 
closed cones. Some plants need the fire's heat to crack hard seed 
coatings in order to sprout. Some plants thrive on the chemicals 
produced from ash leaching into soil. Smaller bushes, crowded out by 
larger neighbors before the fire, flourish afterward in their newfound 
elbow room. The seed caches of ground-dwelling rodents will be 
disinterred, and the still-viable seeds dispersed by ants and birds, 
everyone pitching in to repair their habitat.
In the San Gabriels' chaparral system, more plants survive fire than 
most people think, Beyers said. That's explained, in part, because of 
"fire residence," or the length of time that flames and heat linger in a 
particular spot. Chaparral plant communities don't produce a lot of leaf 
litter or vegetation that accumulates on the ground, which would become 
fuel for fires. Then there is the profusion of wildflowers that will 
debut in the spring. The fire followers: purple lupines, morning 
glories, California poppies, larkspurs, wild sweet peas and snapdragons. 
"Ten years from now," Beyers said, taking in the charred hillside and 
smiling, "you can come back here and never know there was a fire at all."




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