Major Changes Planned in Forest Management Practices : Environment: The philosophical shift was welcomed by the Sierra Club and others. Lumber industry officials are worried that they will end up with less timber.

The U.S. Forest Service said Thursday that it will fundamentally change management policies for national forests in California, reducing some controversial practices, expanding preservation, and embracing such scientific concepts as “biodiversity.”

Environmentalists welcomed the revelation as a significant and encouraging philosophical shift for the Forest Service in California. But they were skeptical about how well the new rhetoric will translate into actual plans and practices.

Lumber industry officials, meanwhile, were worried by the possibility of as much as a 20% reduction in the amount of timber felled in California, the nation’s second-largest timber-producing state. But they accepted the shift in Forest Service policy as inevitable considering rising public concern about forest practices throughout the Pacific Northwest.

Whether the new policies announced by Regional Forester Paul Barker in San Francisco will force his counterparts for Oregon and Washington to adopt similar changes is unclear. But Patricia Schifferle of the Wilderness Society said the changes “definitely acknowledge they have a forest management problem--and they have it nationwide.”

The policy changes also acknowledge a growing insurgency within the Forest Service, which has seen some of its own rangers defect to preservation groups, leak sensitive reports and even start an underground newspaper bitterly opposed to many Forest Service activities.

A number of Western forest supervisors recently confronted U.S. Forest Service Chief F. Dale Robertson in Washington to complain that current policies force them to sacrifice the environment to meet unrealistic harvest levels.

The statement by the Forest Service regional office in California came as scientists in Oregon and Washington challenged the industry’s assertion that cutting old trees and planting new ones eases the so-called greenhouse effect by pulling carbon dioxide out of the atmosphere.

Scientists at Oregon State University and the University of Washington now suspect that logging may hasten the greenhouse effect, a theoretical phenomenon in which certain human activities permanently change the atmosphere, raising the global temperature and radically affecting weather and ocean levels.

In California, Barker sought to remedy some of those worries by reducing the amount of timber cut in the state’s national forests, locking up more land in wilderness areas and expanding research into forest-management techniques that promote “biodiversity,” or the preservation of all the plant and animal species naturally found in forests. Until recently, forests have been managed primarily to grow trees.

“While the national forests in California must continue to do our fair share of producing the natural resources we consume . . . we will strive for a better balance in our program in the decade to come,” Barker said.

In addition to proposing an additional 500,000 acres of wilderness in the state and the addition of as many as 500 miles of federally protected wild and scenic rivers, Barker promised a 40% reduction in the number of acres clear-cut each year.

Clear-cutting is an efficient but controversial logging method in which all trees in an area are cut and hauled away. Besides leaving behind an unsightly “moonscape,” the technique tends to erode soils, foul rivers with silt and drive some animal species to the brink of extinction.

About half of the harvests in California’s national forests are clear-cut now, and Barker wants to reduce that to 30%. He also wants to reduce the total amount of wood harvested to between 1.4 billion and 1.6 billion board-feet annually. The cut has ranged as high as 2.2 billion board feet as recently as 1988. A board-foot is a standard measure equal to 144 cubic inches.

Scientists and environmentalists have long argued that such high harvest volumes would eventually lead to permanent damage to the state’s forests.

“This is a good, solid proposal that makes timid steps in the right direction,” said Bruce Hamilton, a specialist in Forest Service policy for the Sierra Club. “But they still have a way to go before they are really the sensitive stewards of the land that they are supposed to be.”

Hamilton and Schifferle said that while the proposals sound good, they are often less than what they seem to be. The expanded wilderness, for example, is not identified and may include only marginal “rocks and ice” zones foresters do not want anyway. And the size is but half what preservationists had already proposed and only one-fourth of what Congress suggested for possible wilderness status in the California Wilderness Act of 1984.