Issue 7

Blazing Landscapes

by Judy Bolyard Purdy

A home in the country, near the city. Americans in record numbers are coming home to forest and mountain retreats to barbecue on their decks, putter in their gardens, and relax in natural surroundings.

Many newcomers to rural southern retreats have forgotten—or may have never known—that wildfires are as much a part of their new neighborhood landscapes as nature’s symphony at sunset. Idyllic hideaways perched atop a mountain or nestled in a pine forest may one day be in the path of a destructive wildfire caused by lightning or carelessness.

“The entire South is becoming one big wildland-urban interface. Increasingly, people are building homes and recreating in the interface with no regard for the risks,” says John Stanturf, project leader at the SRS Center for Forest Disturbance Science based in Athens, GA. Stanturf oversees a team of foresters, ecologists, meteorologists, soil scientists, chemists, and computer modelers who study the ecology, management, and restoration of southern forest ecosystems. He estimates that wildland-urban interfaces, or “exurban” areas, encompass three to five times more land than urban areas.

“Land use may change from forests to home sites but that doesn’t change the surrounding tree cover,” Stanturf says. “The fire risks haven’t gone away.”

Fire in the Landscape

With few exceptions, North American plant communities—whether forests, prairies, or savannas—have evolved with and rely upon periodic wildfires. For millennia, wildfires have swept across fire-adapted southern landscapes, from the Coastal Plains with their longleaf pine forests to the foothills of the Appalachians. Fires reduce accumulated debris, recycle nutrients locked in dead vegetation, and release seeds packed in cones or other structures that open with fire’s intense heat. Without fire, many plant communities become choked by vegetation and fail to regenerate.

“In certain ecosystems, fires are as important as sunshine and rain,” says SRS plant ecologist Joe O’Brien. “Fire has critical impacts we don’t even know about yet.”

After particularly devastating forest conflagrations occurred in the Northeast and Midwest, Congress passed the Clarke-McNary Act in 1924 to ban fire as a management tool on Federal lands. In the 1930s, Federal agencies also began extinguishing all accidental fires. These fire exclusion and suppression policies, combined with Smokey Bear’s highly effective fire-prevention campaign, created a legacy of wildlands that are now vulnerable to catastrophic wildfires. Private citizens and Federal and private agencies are once again beginning to embrace fire as an important management tool.

The timing couldn’t be better. During the 20th century, the South’s population grew 319 percent, compared with 270 percent for the entire United States. Southern land use has changed and forests are now more fragmented. Forest Service research shows that prescribed fires are a sound and responsible way to protect people and their homes and to ensure the ecological health of fireaffected landscapes. For example, SRS studies show that the populations of many animal species, including bobwhite quail and turkey, increase following a prescribed burn because of improved habitat. But it’s getting more difficult for private and government landowners to use prescribed fire because of changing patterns of land use, public concern, and lack of knowledge about forest management.

The 13 Southern States that comprise Forest Service’s Southern Region receive the most lightning strikes in the contiguous 48 States, with Florida leading the way. The South averages approximately 45,000 wildfires a year, often burning more acreage than all other regions combined. The region also leads the Nation in number of prescribed fires, says forester Dale Wade, who retired from the Forest Service and now trains and advises landowners to use fire as a management tool. “A prescribed burn every few years may be the most effective tool for reducing the risk of damaging, often catastrophic fires,” he says.

Wildland fires often stop only when the fuel runs out or the weather changes. They are more expensive to control and mop up, costing up to 10 times more than prescribed burns, Wade says. The cost to homeowners is also staggering. The United States experienced an especially large number of wildland fires in 1998. In Florida alone the price tag for damages during an 8-week period was estimated at more than $600 million, Wade said. That same year, Congress created the Joint Fire Science Program to inventory fuels and evaluate treatment strategies, setting up a partnership among the Forest Service and the U.S. Department of the Interior Bureaus of Indian Affairs and Land Management, National Park Service, U.S. Fish and Wildlife Service, and U.S. Geological Survey.

Fight Fire with Fire?

The essential role of fire in southern plant communities presents dilemmas for both public and private resource managers. Tensions sometimes arise between resource managers and the people who live in or near the forest because prescribed burns can mean temporary inconvenience. Recurrent fire is mandatory to perpetuate most native southern ecosystems, but should homeowners living adjacent to a wildland be subjected to smoke and the threat of an escaped fire? Should landowners be forced to reduce the buildup of fuels on their property or should they be allowed to let fuels accumulate and accept the increased risk of damaging wildfire? Land managers and homeowners must work together to forge long-term solutions that maintain fire-adapted ecosystems while protecting adjoining landowners and the public from the threat of catastrophic fire.

“The past century has vividly demonstrated that fire exclusion cannot be attained over the long term,” Wade says. “But altered forest conditions and fuel buildup that results from this failed policy make the reintroduction of fire difficult and complex, with a much greater risk of a bad outcome.”

Prescribed fires are often set in late winter or early spring, when temperature, moisture level, and wind direction are more predictable. Because many vegetative communities historically burned during the growing season, an increasing percentage of burns are now done during the warmer months. Approximately 6 million acres of public and private property in the Southeast are treated with prescribed fire each year.

“We need to be burning 30 million to 40 million acres annually in the South,” Wade says. “And you can’t burn just once and be safe. In many situations you’re safe for only a year or two following a prescribed burn.”

A carefully planned and executed prescribed fire poses a very small risk to people’s lives, homes, and businesses. “We use prescribed fires in the wildland-urban interface because they are very effective,” Stanturf says. “In Florida, for example, people can stand in their driveways and watch a prescribed fire burning nearby in a controlled manner.”

To help southern resource managers and private citizens use prescribed fire appropriately, SRS researchers study everything from smoke behavior to fire alternatives. In the past, many fire-behavior prediction models were based on data from the Western States; what’s true for the West isn’t necessarily so for the South.

That includes how smoke behaves, which is the critical issue in prescribed fires, says Stanturf. SRS researchers are studying smoke production and movement to understand, predict, and minimize its effects. (See Related Story: Smoke Get in Your Eyes) Among the reasons that understanding smoke behavior is so critical for the South is the high percentage of roads that penetrate southern forests, compared with many Western States. Predicting smoke behavior is difficult. It becomes even trickier when smoke combines with moisture to form dense shrouds that obscure visibility and endanger motorists, or when it is stirred by coastal breezes invisible on weather maps.

“Smoke will shut us down faster than any other issue because of air quality and safety issues, especially if it drifts over hospitals and schools or across roadways,” Stanturf says.

Another reason the South needs ongoing research is that fragile, fragmented, and historically important forest communities, including “island remnants” in urban areas, are being lost or irreparably changed because of the lack of fire.

Preserving Healthy Ecosystems

It’s undisputed that certain plant communities need fire. Longleaf pine forests, for instance, need to be burned every 1 to 3 years. Yet some haven’t been burned in 50 or even 90 years, says O’Brien, who studies ways to reintroduce fire without causing more harm than good. Forests sheltered from the effects of fire for decades accumulate dense layers of needles on the forest floor, fostering a rich growth of tree roots near the surface. When fire is finally reintroduced after several decades of exclusion, the heat destroys surface roots, and within the next year or two, up to 80 percent of the large longleaf pine trees may die, according to O’Brien’s research.

But prescribed, low-intensity burns aren’t always palatable in urban settings, such as Miami, FL, which is home to threatened rockland pine forests. These open, savannalike, subtropical pine forests grow on thin-soiled limestone ridges and are dominated by slash pine in the canopy. “You have squares of rockland pine forest, often the size of postage stamps, that contain endangered and endemic flower species that evolved with fire,” O’Brien says. “These forests are embedded in urban areas, have been reduced in size by 98 percent, and need fire to survive.”

Like O’Brien, Tom Waldrop studies fire-dependent ecosystems. Team leader for Disturbance Ecology in the Southern Appalachian Mountains and Piedmont, Waldrop is part of a national effort to study fire and fire surrogates—such as herbicides, harvesting, and mechanical mulching—on forest structure and function. Fire surrogates can reduce fuel buildup, but little data exists about their ecological impact and economic effectiveness. In addition to relative costs, what are the effects on seedling germination, species richness, or nutrient cycling? And are essential processes lost when fire is excluded?

The National Fire and Fire Surrogate Study involves more than 130 scientists at 13 sites across the country looking at such issues as insects, diseases, and wildlife. Waldrop oversees research at one site in the Piedmont and another in the Southern Appalachian Mountains. Early results from the study, he says, show that “most ecosystem components are not adversely impacted by prescribed fire or mechanical fuel reduction. These treatments can be used to restore ecosystem structure, function, or both.”

In a separate project Waldrop studies the fire-dependent Table Mountain pines that grow along Appalachian ridgetops. Little is known about fire as a tool for Appalachian and Piedmont forests, where intentional fire was restricted for 50 to 80 years. Waldrop experimented with two fire regimens—a single, high-intensity fire and a series of lowintensity fires—and demonstrated that prescribed fire can be reintroduced into Table Mountain pine forests with little adverse impact. “The goal is to learn to use fire as a more effective management tool in an ecologically sensitive manner,” he says.

His team is also using a type of aerial imagery, called hyperspectral imagery, and topography to develop fuel models for remote, rugged areas of Southern Appalachian Mountains that are hard to traverse and contain a rich mix of plant communities. “Fuel load estimates aren’t as accurate as they could be,” he says, “and ground measurements are time consuming.” The models will yield maps of specific ground fuels, such as mountain laurel, a native shrub which can be explosively flammable under certain conditions.

Waldrop is also investigating two methods for restoring Piedmont forests heavily damaged by southern pine beetles on two different types of sites. One forest is an historical site, while the other is being prepared for a commercial timber operation. Portions of each forest have undergone high-intensity fires—hot temperature fires that burn the tree crowns—and other sections are receiving extensive mulching of the dead trees followed by seedling plantings. Waldrop is comparing plant growth and diversity, soil properties, and the abundance of mycorrhizae (beneficial fungi that help roots absorb water and nutrients) under both treatments.

It’s obvious that some important fire-deprived ecosystems are declining and others may disappear all together. And even though 22 States, including 11 in the South, now have laws to facilitate prescribed burns, the decision to burn landscapes near homes and cities can be a careerending risk.

Meanwhile, forests continue to grow, fuels continue to accumulate, and landscapes continue to burn—whether from a lightning strike or a lawnmower spark.

“There will be big problems,” Stanturf predicts, “if we fail to plan ahead.”