The U.S. Forest Service says it has done a lot more forest thinning to protect rural homes from wildfire than a study by outside scientists indicates - though it still falls short of the goal set by Congress.
National Fire Director Tom Harbour said Friday that by its count 43 percent of the 10.8 million acres treated by federal agencies in recent years was in and around communities threatened by wildfire.
That compares to 11 percent of 7.4 million acres in a study based on a federal database published earlier this month in the Proceedings of the National Academy of Sciences.
Congress called for 50 percent as part of the Healthy Forest Restoration Act of 2002.
Harbour said he could not explain the differences in numbers, but added that thinning directly around rural communities is not enough to effectively combat wildfire, when forests throughout the nation face high risks of burning from a buildup of fuels from a century of trying to put out all wildfires.
"It will not do any of us any good to try to put exclusion zones around communities and have deteriorated ecosystems," he said. "It won't work."
University of Colorado fire ecologist Tania Schoennagel, lead author of the outside study, said reasons for the differences in numbers were not immediately clear, but they may be accounted for by different definitions and constraints in the two analyses.
Their study discounted repeat treatments on the same ground, took into account work by all federal agencies, and likely used a different definition of wildland- urban interface than the Forest Service used, she said.
"There is a really great need to have transparent and consistent definitions of wildland-urban interface," Schoennagel said. "We have to have that clarity so we can have a discussion that allows us to maybe make a better definition of the (wildland-urban interface) or more effective ways to target treatments."
Wildfires burned 5.3 million acres in the U.S. in 2008 and from 2002 through 2006, 10,000 homes nationwide were destroyed by wildfire. Spending on wildfires regularly hits $1 billion a year. The National Fire Plan was adopted in 2000 to control fires as well as spending, but has had little success at either.
The study found that federal agencies working under the National Fire Plan have a tough job because they control only 17 percent of the land in the West's wildland-urban interface. Private land covers 71 percent.
"Our results suggest the need for a significant shift in fire policy emphasis from federal to private lands, if protection of communities and private property in the wildland-urban interface remains a primary goal," the study's authors wrote.
Harbour said he agreed that more needs to be done on private lands to address the growing number of people building homes in forest areas.
"The treatment of hazardous fuels can't be the only part of the solution," he said.
"Local communities, homeowners, local governments - they are just an absolutely essential part in making a difference in the wildland urban interface, which is where much of the risk, which is where much of the threat, which is where a substantial portion of our funds is spent."
This will be the first year that incident commanders in charge of fighting wildfires will have direct access to computer tools to predict how a fire is going to behave, and where the greatest dangers are, Harbour added.
Computer models called Fire Spread Probability Model, known as FSPRO, and Resource and Values at Risk, or RAVER, will be in fire camps around the nation this year, he said.
The Forest Service will still fight all man-caused fires, but incident commanders now have greater latitude to let portions of some naturally ignited fires burn if they are judged likely to benefit the forests, which evolved with fire, and do not threaten homes or private forest lands, Harbour added.
Greg Aplet, staff scientist for The Wilderness Society, said Bush administration requirements that made it too hard for incident commanders to let good fires burn are gone, which should help cut costs and improve forest health.