The communities of scrub and shrub known as chaparral have been the scenes of the biggest — and most expensive-to-fight — wildfires in California, many of which have occurred during the last five years. The increased frequency of these fires, as well as their size and intensity, have accelerated the study of chaparral especially as millions of people and billions of dollars of property now nestle alongside it.
Attitudes toward chaparral and fire have changed drastically since Europeans arrived. During the 19th century and half the 20th, chaparral — found along the Pacific Coast and western edge of the Sierra Nevada mountain range from Oregon's Rogue River Valley to Baja California's San Pedro Martir — was considered a wasted landscape and worthless. Ranchers set it on fire to get rid of it and planted grass for livestock. As more and more people moved to the great scrublands, chaparral was branded an ugly fire hazard and wildfires demonized as a hellish occurrence.
Until the 1960s, chaparral fires, like forest fires, were to be prevented and suppressed at all costs. Next, scientists and public lands managers were convinced that fire was "good" for chaparral and "needed" to burn often to maintain health and prevent more serious conflagrations.
"The latest research search suggests that chaparral has evolved and adapted to fire, but certainly doesn't need it," declares Richard Halsey, founder and director of the California Chaparral Institute, a repository of knowledge on all matters chaparral.
In short, old chaparral is no more fire-prone than new chaparral. One-hundred-year-old chaparral flora (ceanothus, chamise, manzanita and more) is perfectly healthy, Halsey points out. In fact, statistical analyses by scientists found no significant change in the probability of chaparral burning as it ages.
"High intensity wildfire in the shrublands are a natural occurrence and historically there have always been large fires," states Jon Keeley, a research ecologist with U.S. Geologic Survey and a chaparral expert who has recently published his findings in Ecological Applications and other journals.
The problem for the chaparral — and the many humans who live nearby — is the frequency of such fires. There are about 100 times more wildfire ignitions in Southern California today than in 1900, says Keeley, who has tracked the region's fire history back to the 19th century.
"An ecosystem adapted to fire every 60 to 100 years is now burning every 10 years-or even more often," Keeley notes.
Too many fires in the chaparral can compromise or even kill off the plant community, scientists have recently discovered. The native chaparral is unable to regenerate and nonnative species take over, upsetting nature's balance. Invasive weeds and grasses cause even greater fire safety issues and headaches for firefighters than the original scrublands.
Land management policy in the chaparral zone has long been based on the belief that fuel management can limit the size and severity of wildfires. Believing chaparral needed to burn because of an "unhealthy" accumulation of old growth, land managers ordered controlled burns in order to thin the flora and make it more fire resistant. An expanding volume of research is refuting the wisdom of this practice.
Keeley and colleagues have shown that during a century of always dogged and often heroic fire-suppression efforts, the number of fires per decade has actually increased and no significant decline in area burned has resulted.
Researchers have discovered that California's long history of mega-fires (more than 150,000 acres burned) are not linked to old chaparral but to prolonged droughts. Such dry spells lead to an increase of dead fuels. Desiccated undergrowth lingers for many years so the potential for severe fire may continue years after a drought's end.
While fires are indeed a natural part of the chaparral ecosystem, naturally occurring fires are few and far between; lightning is the natural cause of wildfires and lightning storms are rare in Southern California. In most cases, it's humans who start chaparral fires — and the more humans who live amidst the chaparral, the more ignitions.
During the 19th century and early 20th, chaparral wildfires raged for weeks, even months, and got little ink from the region's newspapers. The public was blasé about such blazes because they occurred "way out there" on mountains and in remote canyons far removed from towns and cities. Nowadays, suburbia squats on scrubland slopes, and subdivisions are stuffed into chaparral-cloaked canyons.
Armed with the latest research, Halsey and his Chaparral Institute aim to change the thinking of policymakers. They tell them wildfire risk in Southern California is not a result of poor fire-suppression techniques or old stands of chaparral, but an inherent part of the landscape.
As Halsey sees it, three of the most significant threats to chaparral are: 1) too many people living in a highly flammable environment; 2) humans sparking excessive wildfires; 3) land-use managers clinging to now discredited beliefs about chaparral.
Halsey is convinced that with the latest chaparral research in hand, it will be possible to craft a workable combination of effective fire safety and responsible resource management policy. Unfortunately, he adds glumly, chaparral management shares common ground with so many other endeavors: Money drives policy.
For example, funding from the ironically named Healthy Forests Initiative, a federal program launched by the Bush administration, goes to grinding wide swaths of chaparral into smithereens in the name of fire prevention. What politician or policymaker has the courage to turn down funding for costly "fuel management" programs just because researchers have demonstrated that they're ineffective?
Concludes Halsey: "If we really want to save lives, safeguard property and protect the environment, we need to adapt to the environment instead of making the environment adapt to us."
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