For those who want more commercial logging of America's national forests, the Los Alamos tragedy plays into a stance that is already well rehearsed: that more logging can "reduce the risk of catastrophic wildfires." It is an argument that doesn't hold up.

While Senator Larry Craig, an Idaho Republican, and his allies in the timber industry talk about "thinning underbrush," the real interest of the industry is in gaining access to the last remaining mature forests on federal lands.

In April 1999, the General Accounting Office issued a report that raised serious questions about the use of timber sales as a tool of fire management. It noted that "most of the trees that need to be removed to reduce accumulated fuels are small in diameter" -- the very trees that have "little or no commercial value."

As it offers timber for sale to loggers, the Forest Service tends to "focus on areas with high-value commercial timber rather than on areas with high fire hazards," the report said. Its sales include "more large, commercially valuable trees" than are necessary to reduce the so-called accumulated fuels (in other words, the trees that are most likely to burn in a forest fire).

The Forest Service typically keeps about 90 percent of the revenue from these timber sales. The money has helped finance both the agency's budget and its preparations for more commercial logging. Meanwhile, the logging industry gets rich on cheap timber, and pro-timber members of Congress receive millions in campaign contributions as an incentive to keep this system going. Taxpayers take an enormous loss.

The truth is that timber sales are causing catastrophic wildfires on national forests, not alleviating them. The Sierra Nevada Ecosystem Project Report, issued in 1996 by the federal government, found that "timber harvest, through its effects on forest structure, local microclimate and fuel accumulation, has increased fire severity more than any other recent human activity." The reason goes back to the same conflict that the G.A.O. found: loggers want the big trees, not the little ones that act as fuel in forest fires.

After a "thinning" timber sale, a forest has far fewer of the large trees, which are naturally fire-resistant because of their thick bark; indeed, many of these trees are centuries old and have already survived many fires. Without them, there is less shade. The forest is drier and hotter, making the remaining, smaller trees more susceptible to burning. After logging, forests also have accumulations of flammable debris known as "slash piles" -- unsalable branches and limbs left by logging crews.

In 1994, Jack Ward Thomas, then chief of the Forest Service, said in congressional testimony that fires don't hurt the forest itself. Even fires that kill many trees "in an area from which you do not expect to extract timber" might be "perfectly acceptable," he said. He gave the example of Yellowstone National Park. "It burns up; it burns hot, and the system that's associated with it comes back," he said.

After several decades of federal management that suppressed fires -- with timber sales in mind -- some forests on federal lands have actually become more flammable, since they have been deprived of fire's important natural role of clearing brush under the big trees and returning nutrients to the soil.

Controlled burning has been used successfully for over a decade to reintroduce fire into forest ecosystems. The National Park Service reports that fewer than 1 percent of controlled burns result in "escapes" -- fires that cross their predesigned boundaries. Even then, people and property are almost never hurt.

This does not excuse any carelessness, of course, that may have led to the New Mexico fire, which clearly did escape, and tragically so.

But it would be an even bigger tragedy if we allowed the timber industry's allies in Congress to continue destroying our national forests under the self-serving guise of fire management. Ultimately, our public forests will be safe only when Congress passes legislation to end the timber sales within them.

Chad Hanson is executive director of the John Muir Project and a national director of the Sierra Club.

Copyright 2000 The New York Times Company

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