LANDER -- Not far southeast of here is a vestige of the old American West -- one of the largest unfenced ranges in the United States.

It's a place where 16 stockgrowers, mostly cattle ranchers, graze their animals -- and where thousands of local and nonlocal hunters, fishermen, hikers, backcountry horse riders and wildlife enthusiasts explore annually, but rarely run into one another, except by design.

It's also a place where tens of thousands of people visit every year, from all over the world, to experience a few of the last remaining unspoiled sections of the Oregon, Mormon and California trails.

But the health of the Green Mountain Common Allotment's rangeland is failing, and has been for years, officials say. The federal Bureau of Land Management is proposing to carve the allotment up into six smaller ones, and install nearly 100 miles, and about $1 million worth, of barbed-wire and electrical fences.

A 400-plus page draft of the proposed action, called an environmental assessment, was published last month by the BLM's Lander office, and the public has until June 27 to comment on the proposal and its alternatives.

Following the comment period, the BLM's Lander field manager, Bob Ross, will decide on a final management plan. Or perhaps he'll kick off a more involved environmental impact statement, which, under federal rules, requires a broader and more painstaking analysis of all of the potential impacts of an action.

At least one conservation organization, the Western Watersheds Project, plans to sue the BLM if the agency fails to do this more involved kind of study.

The Green Mountain Common Allotment is over 522,000 acres of open range, 60 miles by 20 miles. If every man, woman and child in Wyoming gathered there, each would have more than an acre of his own to stand upon.

Sections of the allotment have taken a beating from seven-plus years of drought, and more than a century of often harmful livestock grazing. Even though the BLM developed and finalized a management plan less than a decade ago, it has been forced to scrap it, and start over.

Long a source of controversy, this famously unfenced section of federally managed land might, out of necessity, be fenced into smaller sections very soon, in order to help restore critical wildlife habitat and riparian areas, officials with the Lander BLM said recently.

But Jon Marvel, a representative of the Western Watersheds Project, said to break the allotment up into six sections would be a huge blow to Western and American heritage, as well as an enormous cost to taxpayers -- and it all would be done for the sole benefit of a few cattle ranchers.

Fremont County Commissioner Doug Thompson, however, said the proposed action could actually restrict cattle ranchers on the allotment too much, and make it difficult for them to make a living there.