Environmentalists say new plan is aimed at favouring Republicans' friends in logging industry

President George Bush left his holiday ranch in Texas yesterday to head not to the Johannesburg earth summit to discuss saving the planet but in the opposite direction, both geographically and spiritually: to America's Pacific north-west to pick another fight with environmentalists.

He flew to Oregon to announce a new plan to curb forest fires, which in this drought-stricken summer have reached epidemic proportions in the western states.

His scheme, which sounds bland enough and has the support of many politicians of both main parties in the western US, is supposed to allow forests to be thinned and underbrush cleared to reduce the danger of catastrophic fires taking hold.

But green activists say that it is a ruse to give the logging companies unfettered access to protected forests.

During his Texas holiday the president was pictured several times clearing the underbrush on his ranch. This process is regarded as good therapy for presidents (Lyndon Johnson, Ronald Reagan and George Washington used their leisure time in much the same way). It is the hidden agenda that alarms his critics.

"When the Bush administration and the timber industry say this isn't about cutting big healthy trees, you can be sure that's precisely what it is about," Sean Cosgrove, a forest policy specialist at the Sierra Club, one of the country's oldest environmental groups, said.

"We don't have a problem about reducing flammable brush and doing prescribed burning.

"But they want to be in there increasing commercial logging of full-growth trees, and that's what this proposal will do."

The country's national forest covers more than 190m acres (77m hectares). This year about 6m acres were razed - twice the annual average.

Curiously, the dispute has erupted when there is a new consensus that one of the US's most cherished beliefs was, in fact, completely misguided. For decades Smokey the Bear has warned tourists about the need to prevent forest fires, and firefighters tackling a blaze have been seen as heroic figures.

Now it is accepted that burning is a necessary part of the ecological process, and that many of the region's most famous trees - including the giant sequoia and the ponderosa pine - need fire to regenerate. Many of the people who gave their lives fighting these blazes may have died unnecessarily.

The president's plan offers controlled burns and mechanical thinning to prevent fires raging out of control. Gale Norton, the interior secretary, said "Much of the west is a tinder box waiting for a spark", and blamed "a century of well-intentioned but misguided management".

Environmentalists favour letting nature take its course away from settled areas, and building firebreaks round communities.

The White House accuses objectors of worsening the problem. In an official briefing paper it said Oregon's Squires Peak area, devastated by fire after a lighting strike last month, was identified as a high risk area in 1996.

Finally, "after six years of analysis and documentation, administrative appeals and two lawsuits, work was allowed to begin on [thinning] 430 acres of the original 24,000-acre project."

The thinned area was unharmed, the White House said. "In unthinned areas, the fire killed most trees, sterilised soils and destroyed the habitat of threatened spotted owls."

Chris West of the American Forest Resource Council, which represents loggers, said: "The environmental community needs to pull their head out of the sand and be an active participant in this process instead of a grenade thrower."

Mr Bush wants to streamline the planning process to make life harder for objectors, which convinces his opponents that the fires provide him with a handy excuse to change the law to favour an industry that has been a traditional supporter and a generous donor to Republican campaign funds.

"This administration was pushing logging before these fires, it's pushing logging because of these fires and it'll be pushing logging after these fires," Nathaniel Lawrence, of another conservation group, the Natural Resources Defence Council, said.