Setting fires lets crews fight on their own terms

The V-shaped ridge reaches down from the San Gabriel Mountains into La Crescenta, hugged by houses on both sides. Crammed with dense shrubs and oak, it was a torch waiting to be lit.

Instead of letting the fire crawling down the slopes of Mt. Lukens strike the match, the hotshot crews did it, shooting flares into the brush and leaking flame from drip torches.

They were using one of the oldest firefighting tools around -- fire -- to burn the ridge on their terms. Its brush now skeletal, the jutting hill is no longer a threat to Briggs Terrace or Eagle Canyon.

The crews even managed not to incinerate Greta Pruitt’s prized pine tree.

Along with shovels, bulldozers and water-dropping helicopters, the thousands of firefighters battling the Station fire have frequently resorted to setting fires on the fringe of foothill communities, stopping the flames with black earth.

It is a primitive tool, yet one that requires skill, planning and experience to manage -- especially when the burning is next door to street after street of houses.

“That’s not where you want to be. We get very nervous, and we’re always very glad when things go well,” said David Conklin, fire management officer of the Angeles National Forest.

The fire, which has burned more than 147,000 acres, was declared an act of arson Thursday.

Normally it would take about three days of preparation, including clearing lines using little more than picks and shovels, to get ready for a burn like the one on the La Crescenta ridge dividing Briggs Terrace from Eagle Canyon.

But “it was crunch time,” said Nickie Washington of the U.S. Forest Service, who oversaw the burn. It was only “about five or six hours before the fire would arrive” at the edge of this piece of suburbia known as the balcony of Southern California.

The conditions were good: Humidity was up, and the wind was blowing from the south, so it would push against the burn and help keep it out of the evacuated neighborhoods on the other side of the canyon.

Over the weekend, firefighters had talked to Pruitt, 77, who for half a century has lived on 200 acres in Goss Canyon, holding onto what became prized real estate on the west side of Briggs Terrace as subdivision after subdivision filled the hillsides and ridges. She asked them to save a memento from the last time flames raced through: the pretty pine tree that her daughter planted in 1975.

With about 150 firefighters in place, the burn operation began Monday morning on the east side of Goss Canyon. Five strike teams with hoses hooked to engines guarded houses. Hand crews scraped fire lines on both sides of the ridge. Then, section by section, hotshot crews set fire to the slopes. When the last of the ridge ignited, 100-foot flames soared into the sky, churning up a fat plume of smoke visible for miles.

Burnouts are a common practice in battling wildfires, a way of getting rid of pockets of fuel along the fire lines. If the flames stay at low intensity, they do less damage to the land than bulldozers. And they can be used on steep terrain that heavy equipment can’t reach.

Conklin said crews were also likely to conduct a more complicated burn, called a backfire, on several thousand acres west of Mt. Waterman.

Backfires interact with the main fire, which is drawing in air, pulling the backfire toward it. “When those two fires come together, it’s fairly explosive, but there’s nothing left to burn,” said Sue Husari, regional fire management officer for the National Park Service.

“It’s kind of an art; when it works, it’s fabulous,” she added. “It requires a lot of planning.”

As drought, fuel build-ups and climate change have made wildfires bigger and more intense -- and concern for firefighter safety more dominant -- backfires have gained favor.

“I’ve observed more backfires in the last 10 years than I did in the prior 30,” said Rich Hawkins, a veteran California firefighter who is deputy incident commander on the blaze in Yosemite National Park, where backfires are being set.

One of the biggest backfires ever conducted in the U.S. stopped the huge Zaca blaze that marched across the Los Padres National Forest north of Santa Barbara two years ago.

Bill Molumby, a national incident commander from San Diego who oversaw that operation, calls backfiring the most complicated firefighting technique employed. “Backfire carries a lot of risk if you don’t know what you’re doing,” he said.

He estimates that one backfire alone accounted for about 100,000 acres charred by the Zaca blaze -- roughly 40% of the land burned.

Set along a road and bulldozer line on the eastern flank, the big Zaca backfire was 10 miles long.

The scope of such operations has spawned some criticism that they are ballooning the size of wildfires.

But “when the fires get intense enough, you don’t have any choice, it’s the only option,” Husari said. “And we’re trying to keep firefighters safe.”

If it doesn’t work, the merged fires can spread over the fire lines.

Burning near or on private property can also ignite the wrath of homeowners. “People say, ‘Do whatever you have to save my home,’ ” Molumby said. “But after you’ve done it, they say you shouldn’t have.”

That was not the case in this particular area of La Crescenta.

“I’ve got 200 acres of ash and one green pine tree,” Pruitt said during a phone interview Tuesday. The ridge, powdered with ash, resembled the back of a giant gray elephant.

But her ranch home and nearby neighborhoods were safe.

“The confidence [the firefighters] showed in me and the concern and care they gave to . . . the property itself was so unexpected and so remarkable,” Pruitt said. “I will certainly carry this gratitude for them with me forever. I will never forget how good they were.”

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