Bid to save forests is destroying them
Wildfires: Human interference in the natural cycle of thinning-by-fire is blamed for devastating blazes across the West.
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By Heather Dewar
Sun Staff
Originally published June 13, 2002
For 14 years Frank C. "Chuck" Dennis has been working to save Colorado's forests from themselves. Now his efforts are going up in smoke.
"I think my life has just changed," said Dennis as the biggest wildfire in Colorado history rampaged through pine forests and subdivisions southwest of Denver. "All my work was geared toward preventing fires. And now it's burned."
Dennis, a special projects forester with the Colorado State Forest Service, has been fighting Western wildfires for nearly 30 years. He was on the fire line in 1988 when calamitous wildfires consumed more than one-third of Yellowstone National Park, sweeping through overgrown forests that were turned into tinderboxes by a century of fire suppression.
In Yellowstone, in Colorado and throughout the West, land managers who saw fire as an enemy created forests up to 100 times more crowded than nature intended - from about five to 50 trees per acre to 200, 500 or even 1,000 trees per acre, experts say.
"I'd look at those fires and I'd look at the country we have here in Colorado and say, 'The same thing could happen here,'" Dennis said. "But now that it's happened, it's almost hard to believe."
Colorado's forests are falling victim to an unnatural disaster, say Dennis and other scientists who blame mismanagement for the wildfires that consumed nearly 142,000 acres - an area nearly three times the size of Baltimore - in less than two weeks.
The largest of these, the Hayman fire in the Rocky Mountains southwest of Denver, has burned 90,000 acres of ponderosa pine forest since it started Saturday. Also lost are 51 buildings; the famed trout fishing in a 25-mile stretch of the South Platte River; about one-third of the habitat for the Pawnee montane skipper, an endangered butterfly; and some nesting pairs of rare Mexican spotted owls.
The huge fire, which has burned within 35 miles of the city limits, grew very little yesterday, and firefighters who earlier had been kept away from the fast-moving flames came close enough to bulldoze, chop and dig firebreaks that they hope will help contain it.
More than 540 firefighters are attacking the blaze, drawn from the state forest service, local fire departments, neighboring states and the federal government. A Maryland fire crew is on standby if needed, a state government spokesman said.
More than 7,000 people in three counties have been forced from their homes and 1,400 people are poised to be evacuated, with more than 3,000 houses and businesses within range of the fast-moving flames, according to a spokesman for the U.S. Forest Service.
Smoke obscures the Denver skyline, and the reservoir that provides drinking water for most of the metropolitan area is in danger of becoming clogged by silt and ash, Dennis said. The loggers working for him in an experimental tree-thinning program saw their equipment burn up along with their jobs.
"The quality of life where we live will be drastically changed," Dennis said. "When you get these huge crowning fire events, it totally changes everything for 100 years."
The Hayman fire is not yet under control - firefighters say they can't predict when it will be out - and the wildfire season is far from over.
"We have millions of acres vulnerable to these large-scale fires," said U.S. Forest Service ecologist Merrill R. Kaufmann. "We've got room for 40 more Hayman fires."
This isn't how it used to be. Tree rings studied by Kaufmann and others show that before Europeans settled the West, fire danced lightly and often across the landscape, creating a mosaic of forests, shrubs and grasses.
In the ponderosa pine forests of Colorado, flames scorched the trees about once every 50 years, Kaufmann said. The fires were rarely hot enough to kill. In a stand of virgin pines near Cheesman Reservoir, the scientist found fire-scarred trees more than 600 years old and unburned branches that dated to the year 1197, he said.
The frequent fires kept the forests light-dappled and open, discouraged the growth of more flammable trees like Douglas fir, and encouraged a variety of shrubs and wildflowers to sprout on the forest floor.
Then in the late 1800s the land was logged and grazed, and in the newly created wide open spaces, a bumper crop of seedlings grew. Those trees are now 100 to 120 years old, mostly untouched by wildfire and "very, very explosive," Kaufmann said.
Colorado is suffering through a drought so severe that the trees' moisture content is less than that found in kiln-dried lumber, Kaufman said.
In such conditions, a spark from a campfire or lightning strike turns the trees into torches. Flames sweep quickly into their tops, where wind carries them from treetop to treetop, creating fast-moving and frightening "crown fires."
A crown fire "produces so much energy that it is virtually impossible to control," Kaufmann said. "All you can really hope to do is steer it and wait for weather to put it out."
The fires burn so hot that it can make the region's soils impervious to water. It might be two years or more before new growth sprouts, Kaufmann said.
In 1996, such a fire burned along the banks of Buffalo Creek upstream from Denver's water supply. The fire led inexorably to a disastrous flood, Dennis said, creating a large burned-over area that "almost created its own weather."
"Thunderstorms tended to form there and camp out there," he said. "It sounds like a contradiction in terms, but in the two years after the fire we had 13 100-year flood events" - floods so intense they're expected to occur only once every 100 years.
Two people died in the flooding, debris swept downstream blocked the South Platte River, and the city's water supply was badly tainted by ash, silt and debris, Dennis said.
Kaufmann, Dennis and a few other experts began calling for a massive program to thin the region's forests. "We said, 'This is going to happen again, and it's going to keep happening, and we've got to do something,'" Dennis said.
In a demonstration project conducted on the water utility's land, they began a laborious tree-thinning project, cutting back the pines so the tip of every branch was at least ten feet away from its nearest neighbor.
"The idea is that when a fire gets into an area like this, it would drop down to the ground and we'd have a chance to fight it," Dennis said.
Two of the counties where the Hayman fire is now burning have "defensible space regulations" that require forest-thinning for all new construction, Dennis said.
But the approach is opposed by some environmentalists who think it's a subterfuge for logging, Kaufmann said. And many well-to-do telecommuters living on forested 10-acre lots outside the city refuse to alter their cool, pine-scented surroundings.
"They just tend to think it's not going to happen to them," Dennis said.
The thinning project was supposed to draw more public support. The Hayman fire got there first, burning so intensely that it consumed the last of the virgin pine forest and the researchers' test acreage.
The researchers haven't yet seen what remains, but they have heard reports that water utility buildings in the thinned area survived the blaze, and they hope the flames skipped over a few patches of ancient trees.
In any case, the "defensible space" demonstration is done, Dennis said: "It's going to be a major shift toward salvaging what we can and trying to prevent erosion."
Soon, foresters will try to seed the area with grasses to hold the soil in place, but it's virtually inevitable that the urban area's main reservoir will suffer costly damage, Dennis said.
"The fire and flood relationship is common, and there's not much we can do about it," he said.
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