Carrying the Torch : The Idea Is to Deprive a Potential Blaze of Its Fuel by Burning It Off

Capt. Scott Franklin stood on a blackened slope in Stone Canyon, which cuts through the Santa Monica Mountains between Sherman Oaks and Bel-Air, brushed soot from his uniform, and described the devices he uses to set fires.

There is a “helitorch,” a helicopter that drips flaming napalm from a 55-gallon drum. A glorified “gum ball machine” drops small spheres of explosive potassium permanganate. Franklin said he even visited a San Fernando Valley laser manufacturer recently to examine a laser that can ignite dry brush from 100 feet away.

This was strange talk coming from a 31-year veteran of the Los Angeles County Fire Department. But, six years ago, Franklin stopped fighting fires and started setting them.

As vegetation-management coordinator for Los Angeles County, Franklin is in charge of a growing program designed to fight fire with fire. The idea, he said, is to set small controlled blazes in dangerously dry or overgrown brush to prevent it from burning out of control.

Since 1979, the county, cooperating with city, state, and federal forestry and fire officials, has burned about 20,000 acres of brush.

The U. S. Forest Service and state agencies conduct controlled burns in other parts of the country, but only in Southern California, with its annual spate of fires where urban areas meet the wilderness, have county fire departments developed their own programs.

Dozens Planned

Dozens of controlled burns are planned around Los Angeles, Franklin said, the next being a 5,000-acre fire scheduled this week in the Santa Susana Mountains north of Simi Valley.

The overall goal, he said, is to burn about 10,000 acres a year to reduce the amount of brush as fuel in corridors throughout the region that have been scorched repeatedly.

“If we can burn 350 acres and protect 9,000, then we’re way ahead of the game, both environmentally and from a cost-benefit standpoint,” Franklin said.

Most fire experts say that controlled burns make sense in theory, but, because the technique is relatively new, no hard data has been gathered to assess its effectiveness.

Because of the shortage of facts, some foresters and firefighters say it is premature to begin a full-scale effort to control fire with fire.

In the next two months, a task force of officials from the state Department of Forests and the U.S. Forest Service will consult with Franklin and other local officials in compiling the first comprehensive study of the technique and its consequences.

The study, to be made public in December, will probably determine the level of support for controlled-burn programs for years to come, Franklin said.

Tour of Burn Sites

Late last week, he took members of the study team on a tour of some of the recent burns in the county, including one in June at a 100-acre site in Stone Canyon. That burn was the first in a planned series designed to intercept blazes that may sweep south across the mountains.

Stone Canyon was the conduit through which--on a windy November morning 25 years ago--a brush fire that started in Sherman Oaks raced across Mulholland Drive into Bel-Air, destroying 484 of the 2,300 homes in its path.

The pressure to employ preventive measures such as controlled burns has increased as development has rapidly pushed farther up the hills and into the canyons around Los Angeles, Franklin said. There are now 3,500 structures, worth an average of $1.3 million apiece, in the zone that burned in the Bel-Air fire, Franklin said.

In Placerita Canyon in the Santa Clarita Valley, which is high on Franklin’s list of planned burns, housing developments have been built near brush that has not burned since 1919, the first year records were kept. “Those people are on borrowed time,” he said.

Franklin said the Stone Canyon burn set in June, which went smoothly, will be a model for efforts where urban areas join wild ones. The controlled burn was the result of two years of planning.

Brush on about 18 acres below the homes that line the east rim of the canyon was cleared by hand, hauled away from the homes, stacked and burned.

On June 30 and July 1, brush on 78 acres farther down the slope was ignited. Since then, the area has been carefully studied by Fire Department personnel and scientists from the U. S. Forest Service and UCLA. New growth that is greening the hillsides is being catalogued and measured.

Monitoring to Continue

When the rains return this fall, experiments will measure erosion and analyze changes in the runoff to the two reservoirs at the bottom of the canyon.

Most controlled burns are conducted in late spring or early summer, although other times of year are chosen if brush is unusually hard to ignite--such as the sparse brush on the cool north slope of the Santa Susanas that will be burned this week.

Over the next three years, Franklin said, 500 more acres in Stone Canyon will be burned. The goal is hoped to create a “fuel break,” a section of thinned brush that will slow a fire sufficiently to allow firefighters to control it. “In a couple of years, fire will undoubtedly come through here again,” he said. “Our attempt is to intercept it.”

Franklin is convinced that the federal and state study on controlled burns will confirm a number of suspected benefits. Many forestry officials agreed, citing probable effects of intentionally set fires:

The new green growth of young chaparral that springs up in the wake of a fire burns less fiercely than mature stands of brush. Also, when an area is frequently burned, there is less fuel at any one time to burn.

Wildlife seems to thrive after a controlled burn. When fire sweeps through an area, it creates a “mosaic” of open areas green with new growth and mature clumps of brush, providing food and shelter for a variety of animals.

Moreover, by burning brush only at certain times of year and under ideal weather conditions, the impact of smoke from brush fires on Los Angeles’ already polluted air can be dramatically reduced. Wildfires, in contrast, keep no schedule, they say, and in fact tend to occur in the hottest, smoggiest months, when their effect on the atmosphere is greatest.

Finally, controlled burning is calculated to be far cheaper than either bulldozing brush or clearing it by hand. And it is also many times cheaper than fighting a wildfire on the same territory.

Satisfying Growth

On a burned hillside in Stone Canyon, Franklin crouched to photograph bright green seedlings sprouting out of the blackened soil. He said this burn looked like a success. “Look at this growth,” he exclaimed. “This is great. This is all ceanothus. “

Ceanothus, also called mountain lilac, is a woody, resinous shrub that is one of the dominant plants in the chaparral ecosystem. It is the focus of controlled burns. When young and healthy, it is the firefighter’s friend, he said, retaining moisture so that it does not burn with great intensity. But, after 15 years or so of growth, many of its branches die and it becomes “dynamite,” Franklin said.

A pound of ceanothus contains the same amount of fuel as a cup of gasoline, he said. There are 20 to 40 tons of it on the average acre in the hills around Los Angeles. With a Santa Ana wind blowing, fire can consume 100 acres of chaparral each minute. “In terms of energy, we’re talking Hiroshima,” he said.

Under natural conditions, periodic wild fires not only remove mature ceanothus but stimulate the germination of ceanothus seeds, Franklin said. Having evolved over millennia to suit the rigors of a fire-prone environment, these seeds lie dormant until exposed to fire.

If growth of new ceanothus is not stimulated by occasional fires, different species of plants--some of which may present a greater fire risk--can take over an area, Franklin said. “Coastal sage presents a significant fire hazard every five years instead of every 15, like ceanothus. “

Even though the potential benefits of burning are clear-cut, Franklin is quick to acknowledge the risk taken “whenever you drop a lighted match.”

The Main Hazard

The main hazard is that a fire can “escape.” With the best weather forecasting and massive amounts of manpower and equipment, an unexpected shift in the wind and a single flaming twig lofted into the air can quickly create trouble.

Last year, private liability insurance covering damage from controlled burns was dropped, forcing the state to pass emergency legislation to become self-insured.

Despite the risks, no serious damage or injuries have been caused by escaped burns in Los Angeles County, Franklin said.

The most recent close call was in August, when firefighters temporarily lost control of a burn of 3,000 acres of dry brush in Valencia south of the Six Flags Magic Mountain amusement park. Although no damage was done, smoke from the blaze shut down power and forced the evacuation of some parts of the park.

Another potential risk associated with controlled burns is subsequent erosion or flooding. If a fire burns too intensely, the heat bakes the top layer of soil, transforming it into a pebbly layer that promotes flooding and erosion because it repels water, Franklin said.

The key to a successful program of controlled burns, he said, is to reproduce the conditions created by a wildfire--the right amount of brush consumed, the right amount of heat--but to do so without losing control. One goal of the state and federal study is to get a more accurate profile of just what the right conditions are.

“It’s a very fine line,” Franklin said. He said many tools and techniques are being tested to design fires that burn at a particular intensity. The newest device is a brush-crushing machine, imported from New Zealand, that is rolled down a hillside. When the fuel is crushed, it tends to produce a hotter fire. “Each program we do is a learning experience,” Franklin said.

The controlled-burn program has its critics, one of the most vociferous being Klaus Radtke, who left the county Department of Forestry and Fire Warden several years ago to become a private consultant on erosion and fire prevention.

“Every 20 years, they have a new idea,” Radtke said. “Forty years ago, it was the bulldozer. Twenty years ago, the helicopter. Now it’s prescribed burning.”

Other Preventive Measures

Radtke said the Fire Department has oversold prescribed burns while neglecting other preventive measures, such as educating homeowners on the hazards of wood-shingle roofing or encouraging fire- and erosion-resistant land and brush management around homes.

Prescribed burns undoubtedly help in areas where brush has not burned for decades, or in spots that are consistent conduits for fast-moving fires, he said. But, until more research is done on long-term effects of such burns, the technique should be used sparingly, he said.

“There is no data on the response of vegetation to prescribed burning,” Radtke said. “Will the vegetation change to more flammable species or less flammable over the years? We don’t know.” He supports the state and federal study, but said that such research must be carried out over many years, not just a few months, to develop a clear picture of fire’s effects.

If controlled burns being set now were more closely studied, Radtke said, “in 20 years we would be able to conduct a burn with a prescription so fine-tuned that it can predict what types of wildflowers will grow after the fire.”

In Franklin’s mind, though, there is no question that controlled burns can be safe and effective. “When you reduce the amount of fuel from 20 to 40 tons per acre down to three or four tons, you’re bound to have some effect,” he said. He added that careful planning and community involvement will reduce the risks.

“The program is not for the faint-hearted or the uneducated,” Franklin said. “When you let the genie out of the bottle, you’d better have all your ducks in a row.”