Washington

As almost a million acres of American forest burned out of control last week, senators representing western states proposed setting up three wildfire research institutes to study what is becoming an ecological disaster for their region.

Wayne Allard (Republican, Colorado) and Jon Kyl (Republican, Arizona) introduced legislation on 24 June that would allot $15 million to create three institutes — one in each of their states and one in New Mexico — to study ecological approaches to the wildfire problem.

If approved, the money would almost double the $16 million spent this year on a Joint Fire Science Program administered by the US Forest Service, which is part of the Department of Agriculture, and the Department of the Interior. The nationwide programme awards grants to study the wildfire problem, with an emphasis on the natural 'fuels' that feed large forest fires. The new centres would focus specifically on the western United States, although it is unclear how the grant money would be distributed.

Scientists and land managers generally agree on the underlying causes of the problem. Overgrazing has long since stripped the region of grasses that historically provided the fuel for frequent, but far less destructive, fires. That, combined with the Forest Service's decades-old policy of extinguishing all forest fires as quickly as possible, has led to a dangerous build-up of dense stands of small trees among the more sparse large trees. It is the small trees that fuel intensely hot wildfires such as the recent ones in Arizona and Colorado.

There is also general agreement that these fuels must be reduced, either through deliberate 'prescribed' burns, or by thinning out the smaller trees, but each solution has drawbacks. Prescribed burns become more difficult as the edge of the forest becomes more populated. They produce smoke, and can themselves get out of control, as happened, for example, during a fire in May 2000 near Los Alamos, New Mexico (see Nature 405, 264; 200010.1038/35012768).

The alternative approach of thinning the trees, primarily by logging, is the subject of a fierce, perennial debate between environmentalists and foresters in the region. Kyl was among the Republican politicians who blamed the Rodeo–Chediski fire, which began on 18 June and is already Arizona's worst recorded fire, on environmentalists' opposition to logging in national forests. Environmentalists, in turn, have accused timber companies and politicians of using the fires as an excuse to gain access to larger trees that are more commercially valuable, but are not part of the wildfire problem.

Meanwhile, the west is bracing itself for what could be its worst fire season in decades. Already, 2.8 million acres nationwide have burned, compared with 1.6 million in the first half of 2000, which ended with 8.4 million acres destroyed, the most in 40 years. The problem gets worse each year, with more suburban encroachment into forested areas complicating efforts to contain fires, and increasing their economic and human costs.

Julio Betancourt, a research scientist with the US Geological Survey's Desert Laboratory in Tucson, Arizona, who is studying the ecology of the desert southwest, warns that if the region goes into a prolonged drought lasting years — and climatologists see signs that this may be happening — the situation will become even worse. And fires aren't the end of it, he says. When monsoon rains come to Arizona later this month, as they do every summer, run-off from the now barren landscape is likely to lead to serious erosion and flooding.

Betancourt and other scientists worry that even with more money for research, and a more determined effort to eliminate hazardous fuels, this may be too little, too late. According to a report by the Joint Fire Science Program, it “may be possible” to treat 5 million acres a year, but with more than 100 million acres at risk from fire nationwide, “it is uncertain whether this treatment level is adequate to reverse the trend of increasing fuel accumulations and begin to reduce wildland fire problems”.