On a bright spring morning, in the Mills Creek area of the George Washington National Forest, flames crept slowly up the far end of a mountain ridge.

The whitish smoke grew in volume and depth as the unseen fire, pushed by a slow but steady breeze, climbed steadily skyward.

U.S. Forest Service personnel watched the billowing smoke, but made no move to quell the spreading blaze — because the people who normally fight forest fires had set this one.

“Only you can prevent forest fires” is a well-known slogan of the Forest Service which, for all of its value as a caution against carelessness, reinforces the myth that fires are inherently harmful. In fact, carefully controlled burns of forested areas can bring an array of environmental benefits that in the process also undoes a longstanding historic injury.

The suppression of forest fires in the last century has contributed to dangerous buildups of combustible deadfalls and has harmed numerous species. Controlled or prescribed burns performed on public lands are carefully managed procedures meant to reintroduce natural fires and the ecological communities that evolved with them.

Regular burns reduce hazardous fuel buildup and the risk of wildfires. They can help to control the spread of invasive species and diseases, providing habitat and forage for deer and bears. Burning dead wood recycles nutrients back into the soil, fertilizing the growth of saplings, shrubs, wildflowers and mushrooms. Done by professionals, controlled burning is an effective insurance measure for the future health and safety of forests.

Virginia’s George Washington National Forest, along with its southern neighbor, Jefferson National Forest, is at 1.8 million acres one of the greatest intact woodlands on the Eastern seaboard. After a hundred years of fire suppression, this rolling landscape is benefitting from controlled burns — and even managed wildfires — under the supervision of highly trained U.S. Forest Service employees.

The Mills Creek burn was meant to enhance and restore native yellow pines on about 1,180 acres over the next five years. Without fire, according to the forest’ service, yellow pine or oak-hickory forest will become a different forest over time — one dominated by maples, white pines and other species that do not provide the habitat needed by some wildlife species.

Sam Lindblom, with The Nature Conservancy, said, “fire has been a missing component of our mountain ecosystems.” The environmental group supports such controlled burns, which he called a “natural process [that] in turn restores our healthy forests.” Many plant and animal species have become rare or endangered as a result of fire suppression, Lindblom explained, including white oak, once the dominant tree species across the Central Appalachians. Oaks are fire-tolerant, but they have declined in relation to fire-sensitive species such as red maple, American beech and tulip poplar, which have spread with the help of fire suppression.

Controlled burns also can influence the forest’s wildlife composition, he noted. Popular game species such as “quail, deer and turkey thrive in frequently burned areas [which] are full of new growth, insects and other foods.”

“So, put another way,” Lindblom said, “fire is a way to redistribute the diversity of plants and animals to places that are well-suited for those species.”

Anyone who has witnessed the process of a controlled burn can speak to the edgy excitement that has always been part of our association with fire. Crews start them by applying a mix of diesel and gasoline to preselected stretches of dead leaves and woody debris, using drip torches, flare-guns and in some cases, ignition devices called “ping pong balls” dispensed from helicopters. The resulting fire’s growth is closely monitored by crewmembers armed with leaf blowers, rakes and hoes, bulldozers, fire engines and water-equipped all-terrain vehicles to contain and steer the burn.

The Mills Creek fire was overseen by seasoned burn manager Kurt Thompson, who started his career in 1997 with the National Park Service. He and three crew kept tabs on the fire’s progress, regularly checking in by radio with the ignition team on the other side of the ridge that had started it.

Each fire is the culmination of extensive planning that can take a couple of years.

Once an area has been selected for a burn, planners weigh a number of factors as they develop a strategy, spending a third of a year identifying “burn windows” that will last only eight to 10 days.

To ensure that the fire behaved as it was meant to, and to avoid unintended consequences, planners compiled a 104-page analysis, packed with lists, graphs, maps and figures. Smoke impact assessments, with six levels of health concern, were prominently featured in bright colors. While controlled burns have generally been uncontroversial, Thompson said that in some places, with “houses and communities often next door, and concerns about smoke impacts to not only the immediate neighbors but communities many miles away, prescribed fire is a challenge.”

Landscape management through fire is nothing new, Thompson pointed out. Native Americans, and the European immigrants who pushed them out, both set fires, initially to open thick woodlands to attract grazers like bison and elk, and then to create pastures for cattle and sheep.

This burn was set far back in the forest, and while smoke was likely visible from the towns of Stuarts Draft, Lyndhurst and Sherando, it climbed steadily into the sky and dissipated.

Thompson said that spring burns are typically conducted with temperatures around 70, relative humidity about 30 percent, fuel moisture at 10 percent, and winds around 5 miles per hour.

While spring offers optimal burn weather, it’s also a time when some birds are nesting on the ground, such as quail, grouse and wild turkey. Daniel Wright, a Forest Service biologist, acknowledged that some birds, and animals such as turtles, may be unintentionally harmed by fires, but he suggested that most wildlife could escape by either running, flying or burrowing.

In any case, Wright concluded, the habitat improvements from controlled burns “far outweigh these sacrifices. You have to crack an egg to make an omelet.”