Photograph by Mark Thiessen National Geographic July 2008
The American West is burning like never before. In fact, wildland fires have scorched record acreage across the United States. Fighting these wildfires is becoming increasingly expensive, costing upward of $3 billion a year in federal funds. Several factors have contributed to this trend, including nearly a century of what are now widely considered overly aggressive fire-exclusion policies that sought to keep any wildland fire from burning, drought and rising global temperatures, and more people living in areas with a high threat of fire.
Fire is a necessary ecological element, and efforts to eliminate it from this countryâs wildlands have led to significant changes in our forests. Areas that once benefited from periodic low-intensity burns, which clear out flammable tree litter, have been kept nearly fire free. As a consequence, large amounts of fuel have built up, and when fires occur, they now burn higher into the canopy and with greater intensity, making them harder to control. Fire suppression has even changed the composition of some forests, allowing firs and other species fires once kept in check to thrive and crowd out other species, such as ponderosa pine, that depend on frequent flames to grow.
At the same time climactic changes have increased the frequency of fires. The western United States has faced an extended drought and higher average temperatures, and both are associated with longer fire seasons. The late arrival of winter freezes has also extended the snacking season for many wood-eating insects, weakening trees and making them more susceptible to flames.
In certain cases, fire managers will let fires burn in order to restore some of the natural ecological dynamics. But the priority is to protect human lives and, when possible, to keep neighborhoods from going up in flames. Today there are simply more homes and people than ever before in places likely to burn. Americans are rapidly developing the transition area between the deep woods and existing urban areasâ”some eight million homes were built in this Wildland Urban Interface, or WUI, between the past two censuses. That's more homes than in all of New York City, and it means a lot more ground for firefighters to protect.
Shea, Neil. "Under Fire." National Geographic (July 2008), 116-43.
"Total Wildland Fires and Acres (1960-2007)." National Interagency Fire Center.
Gorte, Ross W. "Wildfire Funding." Congressional Research Service, May 7, 2007.
Westerling, A. L., and others. "Warming and Earlier Spring Increase Western U.S. Forest Wildfire Activity." Science (Vol. 313, 2006), 940.
Smokey Bear has been the face of fire prevention for more than six decades and is among the most recognized advertising creations of all time. But he's also closely tied to the policy of fire suppression that most experts now believe has caused ecological harm and contributed to more intense and destructive fires.
Smokey does have supporters who insist that his message is still relevant today. After all, they argue, even if some fire is good for certain species, no one would recommend carelessness with flames as an ecological strategy. Even those who use blazes to accomplish resource-management goals have specific requirements to meet when deciding whether to let naturally caused fires burn (known as wildland fire use) and whether to set fires with specific objectives (proscribed burns).
And while Smokey is still focused on fire prevention, his updated message considers the benefits of some types of fire even as it offers that familiar warning: "Only you can prevent wildfires."
Brown, Hutch. "Smokey and the Myth of Nature." Fire Management Notes, Vol. 59, no. 3 (Summer 1999).
Donovan, Geoffrey H., and Thomas C. Brown. "Be Careful What You Wish For: The Legacy of Smokey Bear." Front Ecol Environ, Vol. 5, no. 2 (2007).
Keeley, Jon E. "We Still Need Smokey Bear!" Fire Management Today (Winter 2001).
Williams, Ted. "Only You Can Postpone Forest Fires." Sierra Magazine (July/August 1995).
Many plants have adapted to fire as a means of self-protection. Others actually need it in order to survive and thrive.
Dense bark on sequoias and certain pines insulates the growing layer below, called the cambium, from damage by lower-intensity understory fires. These fires, which in many forests were once more frequent, burn away leaves, small branches, and other tree litter on the forest floor. They can also kill competing species, such as firs, that are less adapted to this pattern of burning.
Some oaks, redwoods, and eucalyptus trees regenerate after the smoke has cleared, as buds near or below the charred earth send up new shoots. Other plants have well-protected seeds that sit in the soil like time capsules, waiting for the heat of a fire to open them up for germination. Still others keep a seed bank in the treetops, sealed inside thick-walled fruits or resin-sealed, serotinous cones. Should a more devastating canopy fire move through, the fruits will crack open or the resin will melt, releasing the seeds to spawn a new generation. And the new growth will benefit from the post-fire environment, which will have lower numbers of insects and other seed predators.
Dawson, John, and Rob Lucas. The Nature of Plants Habitats, Challenges, and Adaptations. Timber Press, 2005.
Arno, Stephen F., and Steven Alliton-Bunnell. Flames in Our Forest. Disaster or Renewal? Island Press, 2002.
Unlike hurricanes and other tropical storms, which are named using an alphabetical system mapped out years in advance, fires are named only after they break out, usually referencing places near the ignition point. In the case of the Lucky fire featured in Neil Shea's text by the time it broke out, there were so many other fires nearby that the likely place-based names were already taken. So the fire was named for the Lucky Peak helitack base, home of the team that first spotted it.
A constantly updated roll call of fires nationwide is available to the public via the Inciweb Incident Information System, which has the latest news on location, size, and containment status. The National Interagency Fire Center also publishes a daily update that includes comparative statistics for the total area burned to date this year and in previous years.
Worldwide Tropical Cyclone Names. National Weather Service.
The huge boom in residences in wooded, fire-prone areas means less certainty that fire crews will be able to provide protection. But homeowners can take steps to reduce the risk of their houses burning even if the trucks and hoses never reach them. In some communities, building codes mandate specific fire-resistant measures, but even if there is no legal requirement, the right choices can give a home a better chance of surviving the fire season intact.
It's a misconception that fires sweep over an area uniformly, burning everything to the ground. In fact, many fires spread when firebrands—chunks of burning material—float away from a fire and land on flammable matter some distance away. The best way to keep your home from succumbing to them is to conscientiously reduce the supply of fire-friendly material—structural elements, debris, landscaping.
Roofs made of slate, tile, metal, or more-affordable composition shingles are more resistant to firebrands than those made of wooden shingles. For more protection on top, be sure to clear gutters and the roof surface of tree litter such as pine needles, leaves, cones, and small branches.
It's also important to keep flaming particles from getting inside your home via the attic or ductwork. Metal screens over openings such as vents or chimneys can provide important protection.
In the yard, remember to keep combustibles such as tree trimmings, mulch, and even flowers away from the house. Consider a garage, deck, or fence that contacts the main structure part of the building, since it can quickly wick flames to the doorstep. When landscaping, plant and trim trees and shrubs to keep a good distance between the outer branches, so that if one does go up in flames, it will be harder for them to leap to the next shrub or tree.
Other National Geographic Resources
Kunzig, Robert. "Drying of the West." National Geographic (February 2008), 90-113.
Photo Gallery: Wildfires. National Geographic.
"Wildfire Safety Tips." National Geographic.
Last updated: May 30, 2008