Fourth in a five-part series
Forests in the Southwest have become a fuel stockpile. A century of U.S. Forest Service policy of quashing all fires has allowed forests to become overgrown, and now a warming climate is making the problem worse.
Scientists are trying to defuse these green time bombs. Is it too late?
I hike up into the Santa Fe National Forest just outside Santa Fe, N.M. My guide is William Armstrong, the service's fire manager for this forest. He's dressed all in green and is so lanky, he looks like a sapling himself, except his eyes are a piercing blue.
I remark just how lush his forest is, how the Ponderosa pines almost reach out and touch one another. He doesn't take it as a compliment. "They're a plague," he says. "On this forest, it's averaging about 900 trees per acre. Historically it was probably about 40. Here in the national forest, what we're facing is a tree epidemic."
Armstrong has rubbed some people the wrong way with talk like that. But he says forest this dense is dangerous. "We're standing here on the edge of what is known as the Santa Fe Municipal Watershed," he explains. "Imagine a huge bathtub" — a natural bathtub sitting in the mountains around Santa Fe. When it rains, the water flows down into reservoirs. That's where the state capital gets most of its water.
Trees help slow down the flow, but big wildfires take out the trees. They even burn the soils. "They convert from something that's like a sponge to Saran Wrap," Armstrong says. "In the aftermath of a wildfire within this watershed, that would flood like the Rio Grande, for heaven's sakes; that would come down a wall of water, and debris and ash and tree trunks, and create devastation in downtown Santa Fe. Suddenly, they find that the entire mountain is in their backyard."
This is the nightmare city managers have in the Southwest: fire, then flash flood.
Taming The 'Destructive Dragons'
Armstrong supports trimming smaller trees with machines and chain saws. But that costs hundreds of dollars per acre. The service now lets some natural fires — ones started by lightning, for example — burn within prescribed limits. Or they start "prescribed" burns when conditions are safe. These clear out smaller trees and undergrowth to keep them from fueling megafires. Armstrong has done that here.
But people didn't like the smoke, and when an intentional fire gets out of control, people sue. And there's been widespread drought in recent years. These are some of the reasons the Forest Service has reduced the use of prescribed fires.
That leaves Armstrong wondering what to do next. "How do we reduce the intensity so that these fires are not destructive dragons," he says with exasperation in his voice, "but agents of benefit, of recycling nutrients, of maintaining diversity, resiliency? How do we do that?"
To find the answer, I drove six hours across the desert up into the pine-covered mountains of Flagstaff, Ariz. I went with ecologist Wally Covington to the Gus Pearson natural area. Covington is trimming forests there to make them fireproof.
Eighteen years ago, these pine forests had 50 times the number of trees that would have been here naturally. That's because for most of the 20th century, the Forest Service put out almost every fire. That allowed small trees to grow like weeds. In a fire, they become ladders that carry flames up into the taller trees and kill them — crown fires, they're called.
And the overgrowth doesn't just cause bigger fires. Covington says it also hurts the big trees. There's only so much light and water to go around. "The competition with the old growth trees was so intense that those trees started dying at an accelerating rate," Covington says as he shows me some of the big Ponderosa pines still left at the Pearson site. "It's really amazing that any of these old trees are still hanging on."
Restoring The Natural Forests
Covington helped create the 4FRI project: the Four Forest Restoration Initiative. The Forest Service, environmental groups and commercial loggers are collaborating as well. "The goal," says Covington, "was to restore as rapidly as possible some facsimile of the natural Ponderosa pine forest." A forest that would be fire-resistant and also healthier.
We walk through two plots of forest; one is the experimental, the other is what's been left to grow. It's easy to distinguish the experimental site. Here they've cut out the small trees, leaving a few dozen big ones per acre. They've raked up a century's worth of pine needles that had accumulated, and they've spread grass around and then burned it every four years.
The result is an open forest "you could ride a horse through at full gallop," says Covington. That's the way the first settlers described it.
Now Covington wants to treat hundreds of thousands of acres like this. He hopes that will protect them from big fires, but he doesn't know whether that will work yet. He says they've got to find out fast. "You know," he says, "in my opinion we need to get as much done as we can in a hurry, because fire and crown fire is going to come through these lands faster than we think. This is huge." The overgrowth is a bomb waiting to explode, he says, and climate change and drought are the spark waiting to light it.
The Fire 'Was Just Whipping Through The Trees'
The thing is, very little of this treated forest has been put to the test.
One section that was tested is part of the Apache-Sitgreaves National Forest near the town of Greer, in eastern Arizona. Last year the Wallow Fire barreled through half a million acres here, the largest fire in the Southwest since record keeping began around 1900.
It hit Greer hard. I went there and talked to Nadine Stanley at a gift shop at the town's Butterfly Lodge museum, where she works. She was one of about 2,700 people evacuated from the region.
"We got up on the other side of Salt River Canyon," she recalled. "We looked back. You could see the flames way up in the sky. That was scary. How far away is it? Two hours' driving, so 120 miles."
Part of the area the Wallow Fire consumed was a patch that Covington's team from Northern Arizona University had previously thinned out. They'd removed small trees, snags, even shrubs from a hillside. Right next to it, they'd left an overgrown patch intact. One side treated, the other not. When the fire hit, it didn't matter.
When I visit the site with ecologist Michael Stoddard from NAU's Ecological Research Institute, it's clear that the Wallow Fire overwhelmed the team's best efforts at preparing the forest. "The intensity of this fire was just so massive," Stoddard says with a touch of awe in his voice, "it was just whipping through the trees. It didn't care how continuous these trees were."
Stoddard says the fire jumped a 200-yard-wide meadow and up this hill. The flames arced over 50 feet high. The fire front sucked the moisture out of everything ahead of it, so the trees exploded when the fire reached them. The treated area did a little better than the untreated, but it was still cooked.
Ecologist Walker Chancellor is a former firefighter who worked on the NAU project. He bends over and scratches the soil with a twig. It's something in between packed dirt and asphalt. "Hydrophobic," he explains. "When it rains, the water just runs off."
Overwhelming The Timber Industry
Chancellor says even as they keep looking for answers to prepare the forests for the new megafires, the enemy just gets stronger. He says it's not like it was when he fought fires. "We have larger fires," he says, shaking his head. "We've just gotten into these unprecedented, never-seen-before fire behavior that is scary."
And scientists here say the warming climate will only make things worse.
Even without climate change, the size of the job is overwhelming. The 4FRI project has identified 2.4 million acres that need thinning. The Forest Service, which is collaborating in the 4FRI project, has started doing that at the Apache-Sitgreaves forest not far from Greer. Most of the trees at the site I visit are dead, burned in the Wallow Fire. But they're still fuel for the next fire and have to be removed.
I watch a hot saw machine — kind of a backhoe with giant crablike pincers — grab trees and slice through the stems. It fells half a dozen trees in seconds. But that's not fast enough. The local forest supervisor, Jim Zornes, says the Forest Service doesn't have the money to cut very much.
Even if they did, they've got no place to put the timber. "We did have pressure to harvest every dead tree that was left standing within the Wallow Fire," he says. "The problem is, we would have so overwhelmed our local industries, the logs would truly have no place to go."
Zornes says the timber industry has moved out of the region. There are few timber companies who can deal with small trees, those 16 inches in diameter or smaller. Those are what they can cut; everyone agrees the big trees need to stay.
Fighting Fire With Fire, Literally
Zornes says the Forest Service has to negotiate between people who don't want any trees cut and commercial operations that want to cut all they can. The 4FRI project has pulled together constituents from both sides. The Sierra Club is a participant. Historically, says the club's Rob Smith, "We didn't trust the Forest Service." He says many environmental activists saw the service as a friend of big timber companies.
"It has been a transition for many of them," he says, to change their view from "basically 'stop logging in national forests' to 'cut down some of the smaller [trees].' " He says there's now an understanding that too many small trees can be more harmful than helpful.
It's not uncommon to hear people blame environmental groups for holding up logging that would have cleared many of these forests of undergrowth, especially by using the Endangered Species Act. In fact, the Forest Service is one of the most frequently sued federal agencies under ESA. But Democratic Rep. Edward Markey of Massachusetts recently issued a report pointing out that only a small percentage of proposed logging contracts in the region have actually been halted by such lawsuits.
What frustrates fire experts like Armstrong is the slow pace of change. Millions of acres are overgrown, and selective thinning is like spitting in the wind. He says the service literally needs to fight fire with fire, with more prescribed burns.
Armstrong says if people want big forest, they have to accept some fires. Or lose control of them. "For a hundred years," he says, "we've been very good at suppressing them. And now we're reaping that fiery maelstrom. We have fires now we can't stop. And they're going to continue to burn until the landscape is so scarred, and so broken up, there isn't going to be a whole lot left to burn."
Copyright NPR. View this article on npr.org.