By Becky Oskin
Our Amazing Planet
Australia is burning. Extreme heat and drought during the country's summer wildfire season have helped fierce winds spark about 100 bushfires across southeastern Australia.
2012 was America's hottest year on record. Those soaring temperatures (along with persistent drought) pushed more than 9.2 million acres to burn in the West. The damages will top $1 billion dollars, and fires consumed more than 2,100 homes, according to the National Oceanic and Atmospheric Administration.
Parts of both the United States and Australia share a combustible mix of fire hazards, such as an ecology adapted to fire-prone conditions and a climate conducive to wildfires. And every year, more people choose to live in some of the most beautiful and hazardous country around — the wildland's edge.
The destruction will only escalate, scientists predict, until we stop fighting fires in the forests and brush. Instead, the focus should shift to securing homes and structures, as well as applying new research that overturns long-standing conventional wisdom about fire defense, experts say.
"We're losing homes in fires because homes are being put into hazardous conditions," said Jon Keeley, a fire ecologist with the U.S Geological Survey (USGS). "The important thing is not to blame it on the fire event, but instead to think about planning and reduce putting people at risk."
Thanks to work by Keeley and his colleagues, researchers now know techniques that work for firefighters in the Colorado mountains won't help Californians battling wind-driven wildfires in the chaparral.
Don't burn chaparral
In California, as the population sprawls, the fires grow. The loss of lives and property increased every decade in the past century, according to a 2001 study in the journal Conservation Biology by Keeley and USGS ecologist C.J. Fotheringham.
One hundred years of fire suppression is partly to blame. To protect homes, local fire managers frequently set California's chaparral-covered hills ablaze. But the decades spent earnestly "masticating" (mechanically removing potential fire fuel) devil-red manzanitas with trunks as thick as thighs, and the repeated prescribed burns, replaced native chaparral with incendiary invasive species like cheatgrass, according to the USGS.
The decades of effort were for naught, finds a series of recent studies from the USGS and colleagues at the Conservation Biology Institute and several research universities.
Prescribed burning, intended to remove dead wood and fuel before fire season, does help control fires in Western conifer forests, like the tall giants of Sequoia National Park in Northern California. But chaparral isn't forest. It's a dense carpet of woody shrubs: chamise, ceonothus and other plants that cling to steep canyons and ridges.
"I work in Sequoia National Park, and we've had a prescription burning program for the last 40 years, and it's extremely necessary," Keeley told OurAmazingPlanet. "In most of Southern California, it is completely irrelevant. There is overwhelming evidence we've never come anywhere close to excluding fire on this landscape," through prescribed burns, he said.
In Southern California, 29 years of prescribed burns had no effect on reducing the area burned by future fires, a 2012 study Keeley co-authored found. The study was published in the Journal of Environmental Management.
"It's wrongheaded to think there's just one fire story out there," Keeley said. "There's lots of fire stories. There's what's going on in forests, and what's going on in chaparral landscapes, and they're very different in terms of how to solve them."
And when scientists dug up carbon from past wildfires — those that took place before Europeans arrived — they made a startling discovery. Unlike Western forests, coastal chaparral and sage scrub may burn only once every 100 years, and the inland ridges every 30 years. Further tests revealed the shrubs are slow to regrow, taking five, 10 or even 20 years to flower and set new seed.
Frequent prescribed burns, combined with the rising numbers of human-sparked conflagrations, weakens the ecosystem. When chaparral erupts in flames every few years, native species burn through their energy stores and seed stock trying to recover, said Rick Halsey, director of the nonprofit California Chaparral Institute, which advocates for preserving chaparral. As a result of the burns, non-natives take over.
"We're accelerating the environmental destruction of California's most characteristic ecosystem," Halsey told OurAmazingPlanet.
But changing decades of calcified wisdom will be difficult. "There was this mindset that this beautiful ecosystem is unnatural and we need to burn it up because it doesn't belong," Halsey said. "Finally the science got up to speed and said the natural fire regime in chaparral is anywhere from 50 to 150 years, not 10 to 15 years."
The USGS has had success with the National Park Service, which was forced to rethink their approach to fire management in 2001, after losing control of a prescribed burn and nearly torching Los Alamos National Laboratory, one of the nation's nuclear testing labs.
The Santa Monica Mountains National Recreation Area had their last prescribed burn in 2005, said Marti Witter, a fire ecologist with the park. The park lowers its fire risk by mowing open grassland, and leaves chaparral alone.
"The mindset that's out there is so pervasive, and you come up against it all the time," Witter told OurAmazingPlanet. "Anytime we're in a public meeting, there's always someone who will stand up and say, 'if we just did prescribed burning, that will solve our problem.'"
To help spread news of the findings, the USGS Western Ecological Research Center in Sacramento, Calif., will launch a public outreach program this spring, and has already been meeting with local and state fire managers.
Fighting fires with fuel
Clearing chaparral for firebreaks, a gap meant to slow spreading flames, also does little to help fire fighters battle the chaotic infernos driven by California's Santa Ana winds, Fotheringham told OurAmazingPlanet.
"There's really two types of fires: the ones we plan for, and the ones that do the damage," Fotheringham said.
In the fall, fierce winds called the Santa Anas rush down from the California mountains. The winds can be of tropical storm strength (winds less than 74 mph, or 119 kph) at lower elevations and hurricane-strength (74 mph or greater) above 1,000 feet (305 meters).
It's fire season in the West when the winds blow.
Firebreaks can help fire fighters battle small burns in chaparral. Without fire fighters at the breaks, however, flames skip past the gaps, found a study led by ecologist Alexandra Syphard of the Conservation Biology Institute in the June 2011 issue of the journal Forest Ecology and Management.
The non-native species that eagerly occupy open space on fire breaks and in cleared chaparral act as kindling for flying embers, said Fotheringham. The whirling winds carry embers as far as a mile in front of the actual wildfire.
Prescribed fires in central and southern California do not reduce future area burned, as they might in other ecosystems.
Defending your space
In California, when houses burn, blown embers are at fault, not trees or chaparral.
"The primary spread of fire where we lose houses under wind-driven conditions is from embers," Fotheringham said.
In October 2007, more than 2,000 homes burned in Southern California during Santa Ana-driven firestorms. None of the homes ignited from direct contact with flames. Instead, embers blown by the wind — up to a mile ahead of the flame front — landed on flammable materials near houses, according to several studies conducted after the fires.
Researchers with the Western Ecological Research Center analyzed homes in the Santa Monica Mountains and part of San Diego County that burned between 2001 and 2010, during several devastating wildfires in the region. The study, which had some surprising findings, was published March 28, 2012, in the journal PLoS One.
"What really threw me off was the trees don't burn," said Fotheringham, who was not involved in the study but analyzed the data for another research project. "With green vegetation, you have to drive off the moisture before it will ignite. I got to looking around my yard, and I saw all the leaves accumulating everywhere. A lot of what we have for urban vegetation is deciduous, so in the fall, the Santa Ana wind-driven fires coincide with leaf drop. It's a perfect storm."
To really save homes, Fotheringham wants Californians to spend their fall weekends cleaning the nooks and crannies around their homes. Find the fire starters, she said: dryer lint, pine needles and leaves hiding in roof shingles, foundation cracks, decorative shrubs and underneath decks.
"I get so fanatic that sometimes I go out and Shop-Vac my yard, trying to get the leaves all up," Fotheringham said.
California law requires all homeowners to clear a "defensible" space. The guidelines call for trimming branches, keeping tall plants and shrubs away from buildings, and spacing remaining trees and bushes to prevent fire from spreading. Some residents scrape a moonscape around their homes, removing all plants and clearing the land to the dirt.
But time after time, in infernos created by Santa Ana winds, thousands of homes with defensible barriers burst into flames. In the July 2006 Sawtooth Fire north of Palm Springs, homes with more than 100 feet (30 m) of bare dirt clearance burst into flames. In fact, the burning homes set their own shrubs and trees on fire.
That's because clearing land encourages the growth of weeds, "flashy fuels" that easily ignite from embers. Instead of aggressive clearing, a green fire barrier of irrigated, wisely chosen shrubs and trees can help absorb heat and deflect embers, Halsey said. For the most up-to-date advice, visit http://firecenter.berkeley.edu/toolkit.
"Bring a little of the natural environment into your yard," recommended Halsey, who trained as a firefighter to better understand the challenges California must overcome to solve its fire mess. "The quick fix has been to pour more money into the fire agencies, instead of doing the difficult thing, which is planning," he said. "We can do more around communities."
Fotheringham agreed. "It's the planning that's a problem."
Living on the edge
Urban planning makes a huge difference in fire risk, research shows. In Southern California, homes are most likely to burn if they were located off by themselves, or in small clusters, according to the PLoS One study. Building in a wind corridor, where the Santa Anas are fiercest, is also more likely to lead to destruction.
"We know the hazardous fires are driven by Santa Ana winds that follow canyon systems," Keeley explained. For example, Topanga Canyon near Los Angeles burns every other decade because it funnels Santa Anas through its steep slopes, he said.
Housing location can determine the likelihood of structure loss due to wildfire.
While the USGS specifically looked at California, many of the results apply to other Western states, where land use planning is critical for limiting the effects of wildfires in the future.
In Colorado, the 2012 Waldo Canyon Fire was the state's most destructive fire in history, causing $15 million in damage, destroying 346 homes and killing two people.
But Waldo Canyon was an average fire for Colorado, Keeley said. "The Rocky Mountains have fires 10 times that size. What was unusual is Colorado usually doesn't lose homes. But because of urban sprawl, and development moving out into the forest, now when we get a perfectly normal fire, homes burn," he said.
Keeley and other researchers say a major shift in thinking is needed on the part on planners and developers.
Changes in land planning (where people put homes), building more fireproof homes, and landscaping with fire-resistant vegetation will go a long way toward reducing future fire damage, he said. "We see the potential for improvements that can have as much impact as what the Forest Service does out in the wildlands," Keeley said.
"What I want to see change is people stop depending on the Forest Service to put out all the fires," Keeley said. "I want to see homeowners and communities take greater responsibility for solving the problem. It's just wrongheaded to think the Forest Service is the only people who can solve the problem."
This article was republished with permission from Our Amazing Planet.