Prescribed Burning Essay, Research Paper
It’s a promising tool, this idea of prescribed burning to defuel forests and help restore ecosystem health. But it’s risky business, too, and smoke clouds public acceptance.
I THOUGHT FIRE SEASON HAD ENDED. BUT THE SCENT OF PINE SMOKE IN MY NOSTRILS LATE LAST OCTOBER TOLD ME SOMETHING DIFFERENT.
Deep in Oregon’s ponderosa paradise on Winema National Forest, my wife Maurine and I had just finished flagging a new interpretive trail as Forest volunteers. As we drove a remote road just east of Crater Lake National Park, we smelled the smoke. Then we saw flames.
We relaxed a bit when we spotted a yellow-shirted, hard-hatted fire crew from the Chemult Ranger district. They were matter-of-factly tending flank and back lines (see illustration, page 16) on a low-intensity ground fire they’d set earlier. It gradually burned through bitterbrush and light woody debris, mimicking the natural understory fires of old and thus protecting a stand of mature ponderosas. The fire was moving ionals throughout the U.S. In other words, the present emerging technology is a lot more parochial (meaning practical) than political – a refreshing thought.
“Honey, your fire has escaped.!”
“There’s no guarantee you’ll not get a big rip,” (see terminology sidebar, page 57) says a Forest Service fire officer on the eastern seaboard.
“When you’re messing with fire, there’s always a chance one will escape,” echoes his counterpart in California’s Sierras.
“The fuels are tricky…” adds Ron Meyers, who directs prescribed fires for The Nature Conservancy from his base in Florida.
Such concerns are real.
Paul Tine, acting Forest Service fuels specialist for the sprawling eastern U.S. region, remembers well what he calls “the lowest day I’ve ever had in my 18-year career.” As fire boss on a 40-acre prescribed burn on Minnesota’s Superior National Forest in the ’80s, he had taken a little time off to attend a fire seminar, leaving his mop-up crew in good hands after about nine days of solid progress. Then he received a call from his wife.
“Honey, your fire has escaped!” she reported. Apparently a rogue wind had come up, and his prescribed burn had suddenly become a 2,000-acre “project fire,” to use Forest Service lingo.
On May 5, 1980, a 213-acre slash burn in jackpine on Michigan’s Manistee National Forest, fanned by the winds of an unexpected cold front, jumped a major highway, consumed 25,000 acres in one afternoon, took the life of one Forest Service firefighter, and destroyed 44 homes on adjacent private lands.
And early in 1993, a 15,000-acre prescribed fire on New Mexico’s Santa Fe National Forest was going fine – until 60-mph winds unexpectedly struck a small stand of pinyon pine and juniper, producing a crown fire that caught a burning crew off-guard, killing one member (even though the Buchanan fire was later pronounced an ecological success).
Tales like these are, thank heavens, exceptions in the new prescribed-fire technology. And though the learning curve has shown clearly that such fires can help control fuel overloads while improving wildlife habitat and producing other benefits, such incidents have helped to instill a much needed element in this risky business: a little more humility in the face of superior forces.
The prescribed-fire process also presents an intriguing new ecological challenge. As Stephen Pyne pithily suggests in his insightful book, Fire in America, “. . . to remove fire abruptly may be as serious a cultural and ecological event as to introduce it suddenly.”
Today we are capable of doing both efficiently.
On a roll
On the other hand, consider the good news:
The Forest Service’s 13-state southern region is tops in the nation for intentionally torching its forests. According to Marc Rounsville, prescribed-fire specialist headquartered in Atlanta, “We’re burning approximately 550,000 acres a year – more than all the other [Forest Service] regions combined.”
The national forests in Mississippi are the best “producers” in the region, with 135,000 acres burned annually.
Rounsville cites “fuel-hazard reduction” (generally meaning understory burning) as the reason for most of the activity, which takes place in a pine forest area where intentional burning has been around for decades. He also quickly ticks off habitat benefits to wild turkeys, quail, whitetail deer, and swamp bears. Fortunately, the humidity in his region quickly degrades ground fuels, increasing their moisture levels and lessening the chance of a big-time “blowout” like you might see in the West.
Hard against the Atlantic on the region’s Francis Marion National Forest, District Ranger Glen Stapleton adds, “We tell people that prescribed fire is the single most important forest-management tool we have.” He then cites 15,000 to 20,000 acres a year burned on his 120,000-acre coastal-plain district.
Stapleton’s forest is still recovering from Hurricane Hugo (a billion board-feet of timber downed in just a few hours in 1989), but the ranger is focused not only on rehab efforts from that disaster but also on what prescribed fire can do for his longleaf pine ecosystem, which includes the endangered red cockaded woodpecker. His news is good.
Some additional prescribed-fire success stories from across the country:
* Kootenai National Forest, Montana: Ron Hvizdak, fire-management officer on the Rexford Ranger District, reports, “We’re burning maybe 15,000 to 20,000 acres a year, but this forest burned 50,000 acres naturally before fire suppression.” He also reports good chemistry between his fire folks and the community on prescribed burns: help from local volunteer firefighters, field trips by a high-school biology class, and locals who now understand why the process is desirable and accept it.
* Angeles National Forest, California: A prescribed maintenance burn on a firebreak just east of Altadena in the San Gabriel foothills played a major role in slowing the westerly movement of the disastrous Kinneloa fire near Pasadena, one of many that ravaged Southern California in late 1993. The scenario illustrates the benefit of prescribed fire in protecting homes during an urban interface wildfire event, claims fire-management officer Rich Hawkins.
* Boise National Forest, Idaho: The 33,000-acre Star Gulch fire near Idaho City last summer stopped in its tracks when it reached the so-called “Cottonwood natural fuels prescribed fire,” ignited by Forest Service crews in the spring of 1994. “It looked like 75 percent of the green forest was still there – everything else was char,” reported deputy fire-management officer Terry Teeter after a helicopter recon flight.
That national forest has now logged two of the nation’s most compelling examples of how prescribed burns can effectively thwart later wildfires. A similar dramatic event on the Boise occurred several years ago at Tiger Creek, where a crowning wildfire stopped dead in its tracks upon reaching an earlier prescribed burn (see “The Boise Quickstep,” American Forests, January/February 1993).
* Wenatchee National Forest, Washington: Assistant fire-management officer Michelle Ellis reports that previous prescribed burns helped to protect a number of homes from last summer’s devastating Tyee Creek incident, a lightning-caused blaze that burned 140,000 acres east of the Cascades.
* Daniel Boone National Forest, Kentucky: Fire managers this year activated their Incident Command team, normally used for fire suppression, to conduct a major prescribed-fire effort for defueling purposes. At press time the team had completed most of the targeted 8,000 acres, the largest such burn in the forest’s history.
Grandstand of the Sierras
The examples are convincing. But when you contrast them to total acreages under forest management – perhaps a million or more acres on a given national forest – you realize there’s a lot more progress to be made.
“At our current [prescribed burning] pace, I feel we’re treating about one-tenth the acres that were burned in 1900 through the natural process,” says Dave Bunnell, who coordinates the Forest Service’s prescribed-fire program from the National Interagency Fire Center in Boise, Idaho. I personally feel that figure might be low.
Still, there’s hope. California’s Sierra Nevada mountains are probably the nation’s first large eco-region where fire is being encouraged to regain its traditional role – that is, burning regularly in low-intensity mode rather than in intense conflagrations that create ash-black eco-disasters.
Like a huge grandstand reaching skyward, the Sierras rise gradually eastward from the state’s Central Valley – first as nut-brown grassy foothills, then as chaparral and manzanita brushlands in wild canyons, then as sprawling mixed-conifer forestlands of true nobility. Then John Muir’s 500-mile-long “range of light” attains pinnacle and peak status on the “back row” of the grandstand, leaves forests and their fuels behind, then plummets to the Nevada desert below.
The southern and central parts of the range are a great place to experiment with prescribed fire, because predictable westerly winds from the Pacific will eventually lead most forest fires to solid, fireproof granite – your ultimate firebreak, with few towns or ranches in harm’s way.
Probing this wonderland with an eye toward prescribed fire can stir the soul of a fire-conversant observer:
* On Sequoia National Forest at the southern end of the range, Bob Rogers reports modest beginnings – 200 to 500 acres of “management-ignited” fire per year, with sights set on 30,000 acres, and special emphasis on the Kern Canyon, one of a series of “chimneys” that efficiently channel air rising from the bone-dry foothills during fire season. A prescribed fire set early in the ’80s significantly slowed the 15,000-acre Pierce fire in the canyon several years later, Rogers reports.
* In Yosemite, specialist Caroline Lansing reports that 75 percent of the acreage of that national park is considered to be in a prescribed natural fire zone: Lightning fires will be allowed to burn under conditions decided upon in advance, with fire specialists keeping close track of each fire’s progress. Some 52,000 acres have thus been allowed to burn there over the past quarter-century. In addition, management-ignited fires on some 1,300 acres a year, mostly on the fuelly floor of Yosemite Valley, are set annually for defuelling and wildlife-habitat enhancement purposes.
* Stanislaus National Forest, immediately north of Yosemite, is probably the most aggressive prescribed burner in California. Fire-management officer Larry Caplinger describes 15,000 acres of management-ignited prescribed burns per year, then adds, “We may go to 50,000 acres a year in 20 years.” Some near-term burn targets: 3,000 acres of highly fuelled forest-lands next to Yosemite, a critical brush-forest interface involving another 3,000 to 4,000 acres, and other high-priority protection areas where hundreds of fuel-surrounded homes crowd national-forest boundaries.
* On Eldorado National Forest west of Lake Tahoe, and farther north on Plumas National Forest near Mt. Lassen, fire officers can demonstrate that previous prescribed fire can slow or stop major forest fires, open habitat areas for grazing and forage, and in some cases help protect homes from approaching wildfire.
But John Maupin, fire-management officer on the Plumas, emphasizes that one prescribed burn seldom does the trick, citing historical three- to 15-year cycles of natural fuel-reduction burns through much of the West.
“Tomorrow if you could [prescribe] burn the whole western national-forest system, you’d still have to commit to a long-term burning program,” he emphasizes.
In other words, in prescribed burning you burn again and again until natural fires can – at least in some areas – take over the process without torching the infernos we are experiencing today.
Smoke in your eyes
The risks of prescribed fires and the optimistic performance reports are two quantifiable factors. But a tricky card remains in the deck: smoke.
What about our national push for clean air?
There is cause for concern when you consider that air from a Forest Service prescribed burn is occasionally heavy enough (during inversion periods) to close down a state highway in South Carolina, or to cause an international airport in the same region to go to IFR (instrument flight rules) for a day.
Another factor: hordes of people annually flee our cities for a breath of fresh air, and they have little tolerance for the “air pollution” caused by prescribed burning.
Smoke is indeed the biggest potential impediment to prescribed burning in the U.S., where the Clean Air Act is in place. No matter that turn-of-the-century surveyors recorded days of paddling canoes through heavy smoke in the Great Lakes region, or that Oregon Trail journals are replete with entries about smoke and haze – in both cases probably the result of a combination of lightning- and Indian-ignited fires. In other words, much of our continent was already a very smoky place when White Man arrived.
Is the clean air we value so much really the natural condition in our forests? Or have we invented a more attractive substitute that is forest ecosystems running smoothly, a biological pump that drives the cycle of life. Here in Alaska, the very ecological health of our cold forests depends on fire. Without it, there is little diversity in animal or plant life, and the forests become more fire-prone.
Prescribed fire offers an economically and environmentally acceptable means of rejuvenating Alaska’s forests, where the annual rate of decomposition is only about two percent. This sluggish decaying process is due to long, frigid, dark winters and the fact that in much of the state, decay-resistant organic materials are underlain by permafrost. Under these conditions, the forest floor continues to thicken, tying up valuable plant nutrients.
Controlled burning can effectively reduce forest-floor buildup of mosses and dead vegetation, especially in spruce, the most widespread forest type in interior Alaska, and he type with the highest fire frequency. Periodic burning allows smaller fires that do less damage than large,intense conflagrations.
Land managers have identified conditions that must be met before the first drip torch is struck. The burn’s purpose and objectives must be clear, and established parameters must be followed. Critical factors include the burn area’s size, location, elevation, land form, soil type, vegetation including fuel load, climate, wildlife, and habitat. Other considerations include agency policy, funding, air quality, safety of people and property, and access. And, of course, weather and environmental conditions have to be suitable.
In addition to defueling forests, fire can create profound benefits to wildlife:
Several years ago a prescribed burn was torched on a three-acre tract in interior Alaska, conducted jointly by Alaska’s Department of Fish & Game (ADF&G) and Department of Natural Resources’ Division of Forestry (DNR) and the U.S. Bureau of Land management. The purpose was to determine the economic feasibility of using spring fires to improve wildlife habitat in marshes. the flash-type fire raced through light fuels in marsh grass. The burn was monitored for several years, and each spring the burned ground’s warmer and richer soils greened up seven to 10 days earlier and stayed green seven to 10 days longer in the fall.
In 1994 ADF&G and DNR allowed certain areas to burn during a 23,000-acre wildfire in the Delta Junction area. It was a hot burn sparked by lightning, in mostly black spruce forests. Improved habitat for moose, bison, and other creatures is expected over a large portion of that burn.
Biologists in the Kenai National Wildlife Refuge are drafting a moose-management plan that includes burning some 2,000 acres perpetually to maintain a healthy population. The plan will sustain moose numbers of about 6,500. Recurring fires will maintain habit at diversity by creating a mosaic of different-aged forest communities, and in the process reduce the possibility of disastrous wildfires.
Prescribed burning is one of the options being looked at by foresters in south-central Alaska struggling with the worst beetle outbreak ever in all the 50 states. Millions of acres of prime while spruce have been killed. Compounding the problem is that patches of resin flow down the bark of infested trees, providing a hazardous secondary fuel and greatly influencing fire behavior.
As an experienced game biologist, I sometimes react emotionally to the visual impact of a recent fire. But often in a week the burn area will be bursting with new grass shoots, followed by pink fireweed, tiny green willow, aspen, and birch sprouts. Research confirms my personal observations that what appears to be terrible destruction is really Nature renewing the land and the creatures thereon.
Wildlife is a dynamic force in the ecology at boreal forests, and Alaska’s resource managers will continue to fine-tune the use of fire to ensure a healthy, diverse, and productive ecosystem for all life.
RELATED ARTICLE; TNC’s Fire Setters
A few decades ago, the idea of intentionally torching our most precious natural preserves would have been unthinkable. No longer.
The Nature Conservancy, whose purchases and protection of special ecosystems worldwide has become legendary, conducted its first prescribed burn on North Dakota prairielands in the 1970s. It was done to improve wildlife habitat and help endangered plant species recover on sensitive lands. Today TNC’s burning program has expanded to include some 175 different grassland and forest settings, as resource managers carefully study the ecological effects of fire.
A newsletter titled Rx Fire Notes, with catchy headlines like “Are You Reducing Your Duff?” goes out to TNC’s fire specialists worldwide, as the organization burns nearly 46,000 acres of wildlands annually.
RELATED ARTICLE: A Culture of Fire Starters
The concept of human-ignited prescribed fire may sound glitzy or high-tech, but it isn’t nearly as new as you might suppose. Indeed, we are a nation of people who start fires for specific useful purposes. Our “prescriptions” for various kinds of blazes have been as varied as the characters who kindled them:
Back in 1879, on what is today’s Tongass National Forest in Southeast Alaska, naturalist John Muir set a monstrous forest fire “thirty or forty feet high” to dry his clothes on a rainy night. “It was wonderful – the illuminated rain and clouds…the trees glowing against the jet background” he effused in his Travels in Alaska.
Apache Indians in the Southwest often used fire to send up smoke signals, burn out forests controlled by their enemies, and improve hunting habitat. And they used smoke to imaginatively corral game over thousands of years, as did other American natives.
So-called “controlled fire” was used in New Jersey as early as 1928 to reduce fires along railroad rights-of-way, while pioneers of the Allegheny mountains burned huge expanses of their homeland to thin undergrowth for hunting purposes, according to fire historian Stephen Pyne.
As a military-like force of Forest Service fire suppressors gained expertise and momentum following an awesome fire blowup in the northern Rockies in 1910, White Man combined his macho ruggedness with military tactics and high technology to control wildfire – to a point.
And now comes “prescribed fire.” It seems a bit odd that today we marvel over our newfound ability to reintroduce fire into our forests – something many generations of our predecessors knew all about.
RELATED ARTICLE: Coming to Terms with Burns
Over the past several decades, as we have come to better understand and predict fire in the forest, the new science supporting prescribed burning has acquired its own specialized vernacular:
Big rip: A prescribed fire that takes off aggressively on its own. A term used mostly by firefighters.
Escaped fire: A planned fire that gets out of control.
Defuelling: Intentionally reducing the “fuel load” in a forest by prescribed burning or by mechanical thinning.
Drip torch: A can of liquid fuel with a long spout, burning lightly at the end. Used to ignite prescribed burns.
FMO: Fire-management officer, often in charge of both prescribed and wildfire operations.
Fuel downloading: A term describing the reduction of fuels – trees, slash, brush – in a forest.
Let-burn: A no-no term these days. This policy of letting fires burn in some cases was going fine until the million-acre Yellowstone National Park blowup in 1988, when lightning fires allowed to burn went out of control big-time.
Out of prescription: A fire burning outside its planned conditions.
Prescribed burning: Fires intentionally or naturally set, and allowed to burn under specific conditions of humidity, temperature, wind speed, and fuel moisture, and within a planned geographic area. Each fire has its own “prescription,” which theoretically guarantees control.
Prescribed natural fire: Fire, usually set by lightning, that’s allowed to burn “within prescription” in a given area, then watched closely. It poses little threat to life or properly. Such fires are often located in the outbacks of national parks and, more recently, on national forest Wildernesses.