While President Bush pushes a plan to increased thinning in the national forests and around homes, some scientists are warning that there is little or no evidence that forest thinning will prevent future record-setting fires like the ones experienced throughout the West in the last few summers.
“By and large we really don’t know enough to make very definitive kinds of statements,” says Jack Cohen of the U.S. Forest Service’s Fire Science Lab in Missoula.
Two weeks ago, at the site of Oregon’s worst fire in recent history, President Bush announced that he would ask Congress to help hasten thinning projects throughout the country. This means the $400 million that the Forest Service has spent reducing fuel loads in the last two years —much of it through logging—could grow to billions in the coming years.
One facet of the debate revolves around exactly how to thin. The Forest Service maintains that logging is necessary to reduce fuel loads. Conservationists argue that logging is unhealthy and controlled burns are far more effective.
According to one federal study, the Sierra Nevada Ecosystem Project, a thinning process that uses logging needs to be repeated every couple of years in order to be effective, an expensive and difficult proposition to carry out in perpetuity.
But many at the Forest Service don’t like the idea of controlled burns. Tony Leon of the Montana Department of Natural Resources and Conservation Forestry Division says that controlled burns are unsafe given the amount of fuel in national forests and could run out of control, as has happened in recent years.
“I think that President Bush’s thoughts that we need to do something in our forests to reduce fuel loads and reduced the severity of fires is absolutely correct,” says Leon. “In order to do it and make it efficient and help pay the costs, the best way is going to involve logging.”
Other research suggests that massive thinning at the edges of forests in unnecessary. When it comes to protecting homes, the science of thinning is clear and simple, says Cohen. He recently found that thinning only needs to be done within roughly 150 feet of homes.
“In order to protect communities from burning, you can meet the necessary and sufficient requirements to reduce residential fire disasters during wildfires by just addressing the material in a small area,” he says.
Cohen calls this small area the “home ignition zone” and says that if thinning is done properly and leaves behind no slash, fires around a home will not burn as intensely and the buildings will be significantly safer.
“It’s become quite a controversy,” says Cohen of the science behind thinning. “And we really don’t have a definitive answer for some of these questions.”