This season of unstoppable fire reinforces lessons learned when similar blazes destroyed huge swaths of Arizona forest in 2002 and 2003, say wild-land fire specialists.

No amount of tree-thinning and defensive burning can prevent the fires breaking out this spring in desiccated forests blasted with hot, dry winds.

But three large fires burning on the Arizona-New Mexico border demonstrate that hot blazes are more manageable in areas where the forest had been thinned or burned.

• In the Gila Wilderness of western New Mexico, The 88,835-acre Miller Fire burned mostly along the ground through patches of landscape that were historically allowed to burn.

• In the Chiricahua Mountains of Southeast Arizona, 3,000 acres blackened by last year's Horseshoe Fire saved the community of Portal when the Horseshoe 2 Fire erupted. But the fire did more serious damage in areas where there haven't been recent fires.

• The 500,000-acre Wallow Fire in Eastern Arizona rages on and has done severe damage, but flames dropped from the tree canopy when the fire arrived at thinned lines of defense for Alpine, Nutrioso, Eagar and Greer.

Tom Tidwell, chief of the U.S. Forest Service, visited Arizona on Saturday and toured the Wallow Fire as well as the newer Monument Fire near Sierra Vista. In both places, he heard tales of fire becoming more manageable in treated sections of forest.

"I didn't need to be convinced," he said. "I have been talking about this for a couple of years. We need to do more restoration work."

A clear contrast

In the most badly burned portion of the Monument Fire, Ash Canyon, the only green oaks left are the ones that were thinned by the Forest Service along the roads, said Jim Upchurch, supervisor of the Coronado National Forest.

Contrast that with the Miller Fire in western New Mexico, which best represents the long-term benefits of allowing wildfires to burn rather than stamping them out. Fire ecologist Don Falk calls the fire, which has been burning for 53 days, "a glimpse of the way other ecosystems could perform."

"The managers of that ecosystem have chosen to follow a somewhat hands-off fire-suppression policy," Falk said.

Of course, it's easy to let fires burn in the Gila Wilderness.

It has few neighbors.

In more populated regions, it will take decades of careful forest treatment before fire can be restored as a natural land manager.

In the White Mountains, that effort began after the Rodeo-Chediski Fire burned through 460,000 acres of ponderosa pine forest and several mountain hamlets in 2002.

The White Mountain Stewardship Project was formed. It thinned protective swaths around the towns in the path of the Wallow Fire, using the small-diameter trees removed to stimulate growth of a wood-products industry.

In Southern Arizona, plans were made to thin and burn large sections of the Coronado National Forest's "Sky Island" mountain ranges after the Aspen Fire roared through Summerhaven in 2003.

The first of these "Firescape" programs was recently approved for the Huachuca Mountains and the grasslands that border them - the area now being engulfed by the Monument Fire south of Sierra Vista.

The goal is to thin, burn or grind up 30,500 acres of forest and woodland per year for 10 years - depending on the weather and the availability of money for the programs.

800,000 acres burned

Arizona is experiencing a fire season of historic proportions - about 800,000 acres so far - bigger than any other year on record.

Those working on forest restoration say they did not need another wake-up call.

"We're right where we need to be now, but we should have been there 10 years ago," said Ethan Aumack of the Grand Canyon Trust. The trust is one of the partners in the Four Forest Restoration Initiative, an ambitious plan to extend the public/private model of the White Mountain project to 2 million acres in the Kaibab, Coconino, Tonto and Apache-Sitgreaves forests.

"The reality is, if we had done what we are proposing to do 10 years ago, that (Wallow) fire would have behaved very differently," Aumack said.

Falk, an associate professor of natural resources at the University of Arizona, said the government needs to start spending the money it uses to stamp out fires on treating their causes.

"It's totally irrational," he said. "What we're doing now is wasting billions of dollars doing something ineffective, instead of investing half that amount in restoration."

Kyl: "Prevention is cheaper"

Restoration is expensive. The White Mountain project offset some of the cost with commercial uses for the small trees harvested, but the project still cost about $17.5 million to thin 49,000 acres.

But fighting fire is also expensive. These three fires had a bill of $110 million by Friday, and the cost grows by several million dollars a day.

Nationally, the departments of Interior and Agriculture spent $3.567 billion on fire in fiscal 2010, says the President's Fiscal Commission report.

It's time to change, Sen. Jon Kyl, R-Ariz., said in testimony last week to the Senate Natural Resources Committee.

"Although costs are still relatively high, when compared to the costs of suppression and the indirect costs of catastrophic wildfire, it is a small price to pay," said Kyl. "Prevention is always cheaper than fighting the disease."

"We need surface fires"

Fighting wild-land fires is especially costly when those fires burn close to homes, observatories, ski resorts and communications towers, said Falk.

Those are the areas where fire has been most suppressed, where "fuels" - leaves and pine needles, thickets of small-diameter trees, shrubs and grasses - have built up for a century.

In those overstocked forests, destruction awaits a season like this one when the fuels are at their driest and the winds at their strongest.

It is not the size, but the severity of the fires that is shocking, said fire historian Tom Swetnam.

Swetnam, director of the UA's Laboratory for Tree-Ring Research, said large fires often raged across Arizona's forests in presettlement days.

In some years, they burned the entire 400-mile swath of ponderosa pine forest that stretches from Flagstaff, through the White Mountains, along the Mogollon Rim and into New Mexico, Swetnam said.

It kept the forest parklike, with big meadows and fewer than 100 trees per acre. Now thickets of pine measure in the thousands per acre in parts of the forest.

"We need surface fires, managed fires," said Swetnam, "even if it means a lot of smoke, a lot of fear and some risk."

This fire season should motivate renewed movement on the issue, said Steve Campbell of the White Mountain Stewardship Project. He hopes it does not lead to another round of finger-pointing after years of careful coalition-building.

"This is not any segment of society's fault. It's just the human condition that we're dealing with. Everybody contributed to the problem - environmentalists, recreationists, loggers - we all shoulder an aspect of the blame."

Not everybody will be pleased no matter what is done, said Campbell. The thoroughness of the thinning around Eagar shocked some people, he said, but nobody is complaining now.

"I don't know at what point we're going to have to say: 'Look. We're just gonna have to go do it.' "

Contact reporter Tom Beal at 573-4158 or tbeal@azstarnet.com