Some of the US's pristine forests could soon be criss-crossed with roads for logging and mining as the federal government once again relaxes conservation rules - this time in Idaho.
US national parks are still protected, but at threat are so-called "roadless" areas of national forests. These cover more than 230,000 square kilometres - an area nearly as large as the UK. Bill Clinton banned virtually all development in these areas just before leaving office in January 2001. The Bush administration scrapped this policy in 2005, working out rules on a state-by-state basis instead.
On 16 October, the federal government announced it had opened up more than 1600 square kilometres of roadless forest in Idaho to development, including areas bordering Yellowstone national park (see map).
Conservationists are now worried that phosphate mines may be opened in these areas, which could kill aquatic life by polluting nearby rivers. The problem is unlikely to affect the national park itself, they say, but could damage the ecosystem of the greater Yellowstone, which extends into Idaho.
"The thought of turning these very high-quality environments into polluted phosphate-mining zones is really very troubling," says Mike Anderson of the Wilderness Society, Washington DC. He is hoping a new US president will overturn the policy.