A wall of smoke advances across a vast swath of rugged country in southwestern New Mexico where the nation's wilderness movement was born nearly a century ago.

From the air, the smoke stretches as far as the eye can see. On the ground, firefighters talk about the steep canyons that keep them from directly attacking what has become the largest wildfire in New Mexico's recorded history and the largest currently burning in the country.

Sure, things might look bad. But to land managers and scientists, the record-setting blaze represents a true test of decades of work aimed at returning fire to its natural role on the landscape — a test that comes as many Western states grapple with overgrown forests, worsening drought and a growing prospect for more megafires.

The Whitewater-Baldy fire has destroyed a dozen cabins while marching across more than 354 square miles of the Gila National Forest. A pair of lightning-sparked fires grew together to form the massive blaze.

Unlike last year's megafires in New Mexico and Arizona, this blaze is burning in territory that has been frequently blackened under the watchful eye of the Gila's fire managers.

Starting in the early 1970s, the Gila has been leading the way when it comes to implementing such an active fire management strategy. Instead of immediately dousing flames in the wilderness, forest managers have let them burn as long as conditions are favorable.

The question that the Whitewater-Baldy fire is expected to answer is whether that strategy will pay off with more natural, less intense fires.

"There's a great opportunity here to study a fire like this," said Matthew Rollins, the wildland fire science coordinator with the U.S. Geological Survey's National Center in Virginia.

"The opportunity exists to look at how this fire has behaved differently in terms of vegetation mortality, effects on wildlife and fish habitat and water quality," Rollins said. "We can study how it burned in the wilderness relative to areas with other types of fire management strategies and other types of ignition patterns."

So far, the word from the fire lines is that the majority of the 227,000-acre blaze has burned with low to moderate intensity, not the kind of near-nuclear strength that was exhibited last year with the Las Conchas blaze in northern New Mexico. In that case, entire mountainsides were vaporized, leaving nothing behind but the white ashy skeletons of what used to be trees.

And as for those unburned pockets within the fire's boundaries, Rollins said he believes many of those spots have experienced low-intensity fire numerous times over the last century to make them more resilient.

Previously burned areas have also helped slow the flames on the fire's eastern flank.

"The fact that this is wilderness and the wilderness of the Gila has seen a lot of fires, we are comfortable with allowing it to burn. What we do is monitor it and help steer it around to keep some of the impacts lower than they would otherwise be on their own," said Danny Montoya, an operations section chief with the Southwest Incident Management Team.

Montoya said the rugged terrain has forced firefighters to attack the flames indirectly by starving the fire of fuels along its perimeter.

The smoke also has prevented direct attack from the air. Several helicopters and small planes are helping ground crews with backburn operations.

While a burn severity map has yet to be released, members of the incident management team are estimating that only 20 percent of the fire has burned at high intensity.

Last week, the fire made a 60,000-acre run in one day, scorching mixed conifer at high elevations as the flames were pushed by gusts of up to 60 mph.

That kind of fire can be devastating, experts said.

With fire behavior ranging from active to extreme, it will be some time before the scientists can get on the ground to see how the Gila has fared. Until then, they are working on gathering the decades of research done on the Gila, which is home to the world's first designated wilderness. It was the father of the wilderness movement, forester and conservationist Aldo Leopold, who pushed for the formation of the Gila Wilderness in 1924.

Tree ring data that dates back to the 1500s tells of the forest's fire history and the age of its trees. The perimeters of the Gila's fires along with information about their severity and vegetation mortality for the last century have also been compiled by the U.S. Forest Service.

There's also more ecological data from the federal Joint Fire Science program that can be used for comparisons.

"I think it's going to be a success story for the use of fire for managing forests," Rollins said. "It might not look like it on TV right now, but we haven't had any fatalities or dramatic housing loss like we see in Southern California or it burning so dramatically close to communities like last year's Las Conchas fire."

Experts agree that the Gila will see changes regardless of the severity of the fire. In the worst spots, aspens and other shrubs are expected to take over.

"When we're punching multi-thousand-acre holes in areas of ponderosa pine and drier mixed conifer types with no seed sources surviving, it's very difficult for those conifers to be re-established," said Craig Allen, a USGS ecologist based at Bandelier National Monument in northern New Mexico.

Fire managers are also expecting flooding. As the Las Conchas fire showed, steep denuded areas resulted in walls of water washing down canyons during the rainy season.

Residents in Glenwood are already worried about the prospect of flooding, and federal wildlife managers are concerned about what sediment and ash in the waterways could mean for the native Gila trout.

The U.S. Fish and Wildlife Service is also monitoring two packs of endangered Mexican gray wolves that are situated to the north and east of the fire. Last year, wolves in Arizona were able to escape the massive Wallow fire with their pups, but it's unclear how mobile the packs in New Mexico are since their pups are much younger.

The fire is about 15 percent contained, which much of that being on the fire's northern and northwestern flanks.

On Saturday, the more than 1,200 firefighters who are battling the fire continued to build lines to corral the flames before more threatening winds and dry conditions developed.

"We're going to continue fighting this fire aggressively without putting our firefighters in danger," fire information officer Lee Bentley said. "We're getting as much of a black line as we can around this fire."


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