A few lines tucked into the 1993 federal budget bill funding the Department of Interior granted the agency $150,000 to launch a "scientific review of the remaining old-growth in the national forests of the Sierra Nevada in California, and for a study of the entire Sierra Nevada ecosystem by an independent panel of scientists."

That deceptively modest directive gave birth to a mammoth undertaking. Three years later, after work by a team of 18 experts — who called upon contributions from 19 "special consultants" and 107 additional researchers — what became known as the Sierra Nevada Ecosystem Project (SNEP) issued its monumental final report: More than 3,000 pages of text, charts and diagrams. It pulled together much of what was known to science about the Sierra, a sprawling region encompassing 21 million acres and most or all of 18 counties.

In January, an echo of that 1993 congressional directive rumbled across the California landscape, unleashing a revolution in management of the forests that blanket the Sierra. Immediately controversial, the new rules governing 11 national forests draw inspiration from the SNEP report's conclusions and recommendations, as well as from a host of other recent initiatives, most notably those undertaken to protect the spotted owl.

The new rules, issued by Southwest Regional Forester Brad Powell, represent a significant departure from historic management practices and also constitute one of the rare instances where scientific research appears to have trumped politics in the formulation of public policy. Assuming implementation likewise avoids political derailment — this is far from certain, given the Bush administration's antipathy toward policies that favor ecological values over resource extraction — the repercussions will be felt for years.

The revolution bears a bland bureaucratic title: The Sierra Nevada Forest Plan Amendment. Released January 12, along with an environmental impact statement, it comprises an update to the land and resource management plans for the Modoc, Lassen, Plumas, Tahoe, El Dorado, Stanislaus, Sierra, Inyo, Sequoia and Humboldt-Toiyabe national forests, as well as the Lake Tahoe Basin Management Unit. Together, these forests encompass 11.5 million acres.

The new regulations reflect the growing recognition that national forests provide more than timber and livestock forage — that other forest products, such as water, wildlife and recreational opportunities, now constitute their primary public and economic benefits. The rules also recognize the role traditional logging and fire-suppression policies have played in the growing fire danger in the Sierra, as well as the increased risk to human life and property created by urban incursion into the foothills forest belt.

The rules establish a network of "old forest areas" encompassing more than 4 million acres, where prescribed fire and limited mechanical thinning will be used to maintain natural conditions and maintain suitable habitat for old-growth dependent species such as the spotted owl and northern goshawk, as well as fishers and martens (both members of the weasel family). In areas closest to human communities, limited logging will be encouraged to remove the thick buildup of brush and small-diameter trees that has turned the "urban-wildland interface" into a fuel-rich tinderbox.

Riparian conservation areas will be established near streams, meadows and lakes. In these areas, additional restrictions will be imposed on grazing and logging to protect the habitat of imperiled aquatic species such as frogs, toads and fish, as well as the willow flycatcher, which breeds and nests in riparian vegetation, and the great gray owl, which hunts for prey in undisturbed meadows.

Under the plan, nowhere in Sierra national forests will live conifers more than 30 inches in diameter be cut. On the east side of the range, all conifers larger than 24 inches will be protected. In addition, hardwoods (such as oak) will be off-limits to the saw if they are more than 12 inches in diameter on the west slope and 8 inches on the east.

The plan estimates that 191 million board feet of timber will be available for harvest in each of the next five years, dropping to 108 million board feet annually for the subsequent five years. That compares with an average of 200 million board feet each of the past three years, and an average of 300 million board feet annually over the past decade. The peak year for logging on federal lands in the Sierra was 1988, when 1 billion board feet was cut.

In addition, the removal of undergrowth and small trees to reduce fuel loads near inhabited areas is estimated to produce 35% more wood chips annually during the next 10 years for burning in energy-generating biomass plants.

Cautiously endorsed by environmental groups, the plan was denounced immediately by timber industry representatives and lawmakers from logging-dependent communities. Republican members of Congress urged President Bush to derail the plan, which California Forestry Association President David Bischel called "disastrous."

The regulations have followed a tortuous route. The process began in 1992 when the USFS responded to accusations it was doing too little to protect the habitat of the California spotted owl. The agency imposed temporary curbs on logging and began work on a comprehensive management plan. The first version of that plan was withdrawn just before release in 1996 because it conflicted with the data in the SNEP report, and a subsequent draft was rejected in 1997 by the Clinton administration because it allowed excessive logging. Work on the current plan began in June 1998; it involved dozens of public meetings and drew comments from 47,000 people.

The Bush administration could easily suspend the plan. New Agriculture Secretary Ann Veneman, who oversees the Forest Service, criticized earlier drafts of the plan while she was an attorney representing the Sierra Nevada Access, Multiple Use and Stewardship Coalition, a consortium of groups opposed to Clinton forest policies. Veneman has pledged to recuse herself from decisions involving the Sierra forest plan, but it is unclear who might act in her stead.

Such a suspension could, however, backfire. Last October, three environmental groups sued the USFS, seeking to suspend logging in the Sierra and southern Cascades to protect the California spotted owl and the fisher. The agency in December imposed a three-month moratorium on timber sales throughout the region while it prepared a response.

The new rules for Sierra forests represent the agency's effort to protect those increasingly rare creatures and settle the litigation. Suspending the regulations could put the lawsuit — and the future of Sierra logging — in the hands of a judge. That scenario ought to sound familiar and unappealing to the timber industry and its allies. It is what happened in the Pacific Northwest a decade ago when nearly all public-lands logging was halted by the courts to protect the northern spotted owl.

California Forestry Association: (916) 444-6592.
U.S. Forest Service, Southwest Region: 707-562-9004.
Sierra Nevada Forest Plan Amendment: http://www.r5.fs.fed.us/sncf.
Sierra Nevada Ecosystem Project: http://ceres.ca.gov/snep.