Ron Dungan

The Republic | azcentral.com

FLAGSTAFF — About 60 or 70 firefighters had gathered in a parking lot on the edge of town. They listened closely as the burn boss detailed their mission, which was to set fire to the woods across the highway. He noted the wind speed and weather, terrain, the fuel underfoot.

The burn area was a slope that peeled off A1 mountain, and beneath the mountain was a cluster of expensive homes. The firefighters would have to be on their game and the locals would get plenty of smoke.

There is always smoke after a prescribed burn, said Brady Smith, a spokesman for Coconino National Forest.

The firefighters were tall and short, bearded and clean-shaven, men and women, young and gray-haired. They were dressed in T-shirts and hoodies and baseball hats and the mood was both casual and professional as they moved pens along the map and noted the ignition zones.

Ordinarily, people might be nervous about someone lighting the grass just down the road on fire, but Don Woods, who lives near the burn, took the dogs for a walk as the burn began.

“I’m not nervous," he said. "There’s a fire truck parked in front of my house.”

Woods said he understood the reason for the burn, and would rather have a fire with 60 or 70 firefighters around to watch it than have a big wildfire at his doorstep.

“If there ever was a fire we could be in trouble,” he said.

Correcting for the past

Prescribed burns are based on the idea that ponderosa forests, historically, burned often. They burned when lightning struck, when campfires jumped, when Indian tribes wanted to drive game or clear land. The fires cleaned up the forest floor, so when new fires came they burned cooler, smaller and caused less damage.

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But American settlers didn’t understand fire, didn’t trust it. Americans wanted trees to “harvest” and build things with; the Forest Service was, and remains, under the Department of Agriculture. And so they put out fires whenever possible, which led to bigger fires, which made foresters even more determined to kill fire.

After about a century of fire suppression, researchers realized that fire played a role in ponderosa forests. The bark of a large ponderosa is like a tough, leathery hide that can withstand fire. Some small trees may burn, but others survive; seed growth is stimulated by heat. Ponderosa forests evolved with fire. Excluding it was not only impossible, it was unwise.

Now, managers have begun to bring back fire into the forest, walking a tightrope act of action, reaction, caution and discretion.

Watching the fire, the smoke

The A1 burn began with a test, a decision to keep going. A firefighter gunned the engine of a Polaris, dust hung in the air, there was radio chatter and people moving along the perimeter of the burn area.

After about half an hour, firefighters emerged from the forest, eight or 10 abreast, a wall of smoke rising behind them. They carried cans with long spouts, curled like a pig’s tail, a fuel mixture shooting flame into the grass, lines of flame in their wake.

The lines of fire thickened, then converged. A wind kicked up and the air filled with dust and smoke. A weather report came over a radio on someone’s Polaris and about a dozen firefighters watched as the fire burned back into the forest, driven by the wind.

They held Pulaskis, a tool that is part ax and part pickax, and other hand tools. A few big trees caught fire at the base, the smoke thickened, the sound of a bonfire, eyes teared up and soon the firefighters were off to another part of the burn.

It was over in a few hours.

The final stage was a backburn along a fire line dug earlier in the week. On one side of the line, warmth. On the other, cool mountain air.

About a hundred yards from the fire, the plume was visible, the changing colors — orange, white, the various shades of gray. It sounded like a river rushing by. The flames raced uphill.

Controlled burns save millions

For the past decade, Coconino National Forest has burned between about 8,000 to 22,000 acres each year. The cost of a controlled burn is in the thousands of dollars.

Wildfire costs — manpower, home damage, rehabilitation, property value and other costs — run into the millions.

The A1 fire covered about 500 acres and cost about $66 per acre (for an estimated cost of $33,000), Smith said in an email after the blaze. The cost to fight the Schultz Fire, which burned outside Flagstaff in 2010, ranged between $133 million and $147 million, according to a report by the Northern Arizona University Ecological Restoration Institute.

Smoke is one of the biggest downsides to a prescribed burn. The other might be a fire jumping a line — there are still a lot of areas where fire has been suppressed, areas that have a lot of fuel.

In this case, the smoke was the issue. As he drove away from the fire, Smith talked on his cellphone to a woman who was concerned about the smoke and was considered spending a night in town.

“This is the hard thing. It needs to be done. There’s no perfect time,” Smith said. “Unfortunately it’s a necessary evil because of how long we’ve suppressed it in the past.”

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