Policy Squabble : Forest Fires: The Debate Heats Up

For most of the last 2,000 years, and perhaps for as long as 11,000 years, American Indians have used fire to shape North America’s forests. In the winter, they burned forests high in the mountains to drive elk and deer to lower elevations where they could be hunted. They burned forests and brush around their villages to keep enemies from hiding there and to prevent enemies from burning the villages down.

More significantly, scientists have concluded from studies that have stretched over the last two decades, early Indians also burned meadows and forests to stimulate the growth of highly nutritious grass that lured bison and elk to hunting grounds. When horses were domesticated, burning was done to provide grass for them.

As a result of this activity, combined with natural fires triggered by lightning, “the forests were vigorous and diverse, had many species of wildlife, and were safe places to live,” said forest ecologist Thomas M. Bonnicksen of Texas A&M; University in College Station.

Profound Changes

“When we came along (in the 19th Century) with our European arrogance, we said the Indians were unimportant, so we ignored their role and suppressed fires, and the forests changed profoundly,” he said. Under the suppression policy, both naturally and accidentally ignited fires were put out as soon as they were discovered.

About 10 years ago, however, when experts started to become convinced that fires play a natural role in the forests, the U.S. Park Service adopted a “let-burn” policy in large forests with extensive wilderness areas such as Yellowstone National Park, allowing lightning-ignited fires to die out on their own unless they endangered humans or park facilities.

But that policy ignored the fact that combustible materials such as brush and dead trees had built up in the forest during the three-quarters of a century of suppression. “We . . . said lightning fires could bring the forest back to its natural state,” Bonnicksen said. “That was a major, major error, and a scientifically unsound decision.”

Policy Blamed

That policy, he said, led directly to this summer’s conflagration in Yellowstone, which burned 800,000 of the park’s 2.2 million acres. And, he added, continuation of the let-burn policy would almost certainly lead to other major blazes.

In the aftermath of the Yellowstone fire, many citizens and politicians are urging the Park Service to return to its policy of suppressing wildfires. Experts from both the Forest Service and the Park Service will meet in Washington this month to re-evaluate current fire-control policies and the let-burn policy, which was informally suspended by President Reagan after the fire. Congressional hearings on the subject are also likely.

But independent experts contend that a return to fire suppression would be a serious error. “When you are dealing with a natural ecosystem that has burned historically and that burns naturally, fire-suppression efforts don’t prevent fire, they simply delay it,” said biologist Carl Bock of the University of Colorado in Boulder. “When the fire inevitably does occur, it is hotter and more difficult to manage.”

Instead of suppressing fires or simply continuing the let-burn policy, experts argue, the Park Service should adopt a much more aggressive policy of burning selected areas in parks like Yellowstone in the spring and fall, when such fires can be controlled more easily.

Such “prescription burning” would eliminate the huge amounts of combustible materials that have built up in the decades during which the Park Service aggressively suppressed fires, experts said. Perhaps more important, they would provide areas of vigorous and healthy new growth in the forests that would serve as natural firebreaks, minimizing the risk of future disasters.

Small-Scale Success

Such a policy is already being successfully carried out--at least to a limited extent--in smaller forests throughout the southeastern and western United States and in Canada’s national forests. A new management plan for the Angeles National Forest near Los Angeles would also greatly increase prescription burning there. But the Park Service has not been willing to try prescription burning in Yellowstone and similar parks.

Proponents of prescription burning concede that the lodgepole pine forests of the Rocky Mountains are different from forests in other regions. Fires in the Rockies burn hotter and more intensely than fires in other regions, so that prescription burns would be difficult and expensive to control.

But “at the very least, they could use prescribed burnings to protect high-use areas” such as campsites and structures, and to make firebreaks at park boundaries to prevent fires from spreading into adjacent private timberlands, said fire ecologist Ron Myers of the Nature Conservancy.

Changing Attitudes

Fire suppression was widely adopted in 1886 and reaffirmed in 1916 when the Park Service was established. “Suppression made a lot of sense at that time, and still does in places where there are (housing) developments or human life is threatened,” according to Bruce Kilgore, regional chief scientist of the Forest Service.

But in the last few decades attitudes began to change as anthropologists and biologists studied the natural history of forests more closely. Studies of charcoal buried in bogs and fire-scarred rings in tree stumps and cores showed that fires had consumed forests at regular intervals that ranged from every 15 to 20 years in the Southwest to every 100 to 400 years in the Rockies.

A growing knowledge of botany and biology also has highlighted fire’s natural role in the forests.

Scientists discovered, for example, that seeds of the lodgepole pine are freed from their cones to take root only when the heat of a fire causes the cones to pop open. The burning of brush and bramble beneath a canopy of trees allows room for small mammals to forage and make their home, while the destruction of infested or rotting trees slows insect damage to healthier species.

Fire Spurs Growth

Grass and other foliage grow more profusely after a fire because of the nutrients returned to the soil, and are especially attractive to bison and elk, birds and small mammals.

“Bison are quite clearly attracted by a fire,” Bock said. “They walk out on a burn and lick the ash, then they almost literally stand around waiting for grass to grow. . . . One can imagine historically that they could see columns of smoke for 100 miles, be attracted to the fire and stay for a season before moving on to the next fire.”

Some forestry experts have concluded that suppression leads to larger individual fires. Biologist Richard Minnich of UC Riverside, for example, has made a comparative study of chaparral forests in Southern California, where fires have been suppressed, and Baja California, where they have not.

Using satellite imagery covering the period 1972 to 1980, Minnich found that the Baja area had had a large number of fires, most of them covering only 500 to 2,000 acres. In Southern California, in contrast, there were far fewer fires, but they were larger--generally 20,000 to 50,000 acres, and sometimes as large as 200,000 acres. An ongoing study of historical records from 1920 to 1972 supports similar conclusions.

“There were just an unbelievable number of fires in Mexico, but there were few large ones, so the total area burned is about the same as in the United States,” Minnich said. When a fire starts in Mexico, he noted, it quickly runs into a previously burned area where there is no fuel, and it stops.

California Results

But in California, suppression has created large areas with lots of fuel. If a fire starts after a dry season, particularly when Santa Ana winds are blowing, it can quickly get out of control and devastate large areas, he said. “All we see is a worst-case scenario. No one remembers what a fire in normal weather is like,” he added.

Minnich also noted that “most of our forests in Southern California haven’t had any fire whatsoever this century. . . . The stands are getting denser and denser, setting the stage for really bad conflagrations.”

Based on studies similar to Minnich’s, officials in the Angeles National Forest have for 15 years been burning 5,000 to 10,000 acres per year in the 693,677-acre forest to try to reduce future damage, according to fire management specialist Gordon Rowley.

A new management plan taking effect this fall will increase the yearly burn to 20,000 acres, he said. “With modification of the fuel (through prescription burning), we’ll be able to stop the severe damage, although we may not be able to stop the large fires caused by Santa Anas (winds),” he said.

Reproduction Suppressed Too

Prescription burning has also been carried out in the Sequoia and Kings Canyon national parks in Central California for about 20 years, although foresters there had a somewhat different reason for beginning the program. “We learned that the giant Sequoia species don’t reproduce without fire, and that a century of fire suppression had tremendously reduced reproduction,” said fire management specialist David Graber of the Park Service.

Critics of prescription burning argue, however, that the situation is different in Yellowstone and other parks in the Rocky Mountains where fires recur less frequently and tend to burn more intensely and over wider areas. Under such conditions, fires are more difficult to control and may require more alteration of the park--such as the formation of artificial firebreaks that interfere with the park’s environment--than is required at smaller parks.

In fact, opposition to such environmental alterations may have impeded the battle against the Yellowstone fire. Critics charged that the Park Service refused to allow firefighters to make firebreaks in many ecologically sensitive areas and did not allow bulldozers and other heavy equipment to be used at many other sites.

“The same considerations would be important in prescription burning, but you could use more hand tools and make greater use of fire (for making firebreaks) than you can when a fire is already going,” said Charles George, project leader for fire-suppression research at the Forest Service’s Intermountain Fire Research Laboratory in Missoula, Mont.

Canadian Experience

But prescription burning can work in forests like Yellowstone, others say. Some point to the experience of Canada, where the Canadian Park Service has been using it experimentally since 1979 in the Banff, Jasper and Elk Island parks, among others, according to ecologist Nikita Lapoukhine.

The burning program was undertaken, he said, “because the forests were changing, as well as the wildlife.” Desirable black spruce and lodgepole pines were being displaced by less desirable balsam, which is normally destroyed by fires. Shrubs were invading the forest, making it more difficult for the trees to reproduce, and budworm infestation was much more widespread than it is in forests where fires help control it.

Lapoukhine noted that there has been little controversy about prescription burning in Canada, and “we have had no trouble at all in controlling the burns.”

Money Is a Problem

The Canadians also have not had to deal with one other problem facing the U.S. Forest Service: lack of funds.

“There is a near endless pot for emergency firefighting, but a very limited budget for prescribed burning,” the Forest Service’s George said. “If we could have some of that firefighting money for prescribed burning, we wouldn’t need as much for firefighting.”