Seems just yesterday the Mountain West was big enough for everybody: Families rugged enough, or crazy enough, to live in isolation and extreme weather conditions, as well as summer tourists and winter skiers spending a bit of time in the wide-open spaces, were rewarded with the fresh air, the beauty and the tranquility we all treasure.

From a burgeoning world population, though, has come spillover of homosapiens in excess — all wanting some of the elbow room and quietude long afforded by America's public lands.

And into the mix came machinery: Tote Gotes 50 years ago, high-tech dirt bikes now, along with their four-wheel cousins, the all-terrain vehicles. These internal-combustion marvels move their passengers up hills that challenge mountain sheep — and across grassy flats with breathtaking speed. The notion of reducing the vehicles' loud growls to a reasonable level mostly was lost on manufacturers — or muffler-altering owners.

More and more people, on more and more motors, have been on a decades-long collision course with trekking purists — and with ranchers, whose trucks taking them to their bargain-rate grazing leases, and livestock, aren't exactly gentle on the land.

Now the Santa Fe National Forest is in the process of issuing maps proposing to limit motor travel on terrain which, until now, has been open unless posted off-limits. Once its travel-management plans are made public, probably this week, the public will have 45 days to comment on them.

Expect the more macho members of the motor-vehicle lobby to demand more miles of trails for trucks and ATVs — and expect the more vehement tree-hugging groups to demand pristinity.

Is there a middle ground? Maybe. It doesn't lie where many officials would like it — limiting off-road vehicles to established roads. Yet, when ATVs are capable of carving their own four-wheel roads with repeated runs over recently virgin land, how are the florestas expected even to define roads?

Some of the routes ripped out of the vegetation, and some of the single-track trails widened by hordes of ATVs, clearly must be closed. The vehicles' ability to run up and down steep slopes, and their drivers' desire to do so, accelerates erosion — regardless of the more conscientious off-roaders' efforts to repair trails.

Yet, for all the fragility of our region's land, there's enough of it to allow off-roaders to romp — probably where they've already messed it up. The first goal of the travel-management plan, perhaps, should paraphrase the ancient medical advice of Hippocrates: First, allow no further harm; after that, choose the worst-injured, most immediately threatened, land for reclamation.

As for the areas where off-roading will be allowed, be ready to spend money patrolling to keep riders where they belong — and to maintain the trails. America has millions of off-road machines, their owners dying for a chance to twist the throttle. Between locals who love having a short hop to the outdoors, and visitors who haul pickup-loads long distances to those same outdoors, the wear and tear on places like Glorieta Mesa is sure to get heavier.

Is the mesa about to become one big ATV park? For all the environmentalists' concerns — and the motorheads' wishes — both are likely to be heard. The broader-minded enviros will concede some rambling room for ATVs — and the more responsible of the off-road riders will admit that not everyone behind the handlebars has given the land, its plants and its wildlife the respect they should have gotten.

Still, our region is in for a rousing debate — and downright shouting — over the travel-management proposals.

We wish forest officials well with their efforts to achieve a sensible balance.