Every week, rogue drivers on burly all-terrain vehicles and powerful dirt bikes carve new trails up steep, rocky ridges and across open meadows on the Arapaho National Forest in northern Colorado. On the edges of the forest, off-roaders rip across private property and race down roads belonging to people who thought they’d find quiet if they built a home five miles from any pavement.

Spence Sedacca, who lives on 35 acres bordering the national forest and rides a four-wheeler himself, is deeply dismayed by this behavior. "They just flat don’t care," he says.

And despite new rules from the U.S. Forest Service, things may not get better any time soon.

In mid-July, the Forest Service released a proposed rule to consistently manage off-highway vehicles (OHVs) across the country’s 155 national forests and 21 grasslands. But environmental and off-road groups alike worry that the rule won’t do enough to curb increasing damage.

From Washington to Arizona, off-road vehicle use is skyrocketing. Nationwide, there were 36 million OHV riders in 2000, seven times as many as there were 30 years ago. Forest Service Chief Dale Bosworth lists unmanaged recreation, primarily OHV use, as one of the top four threats to the nation’s forests. Two of the other threats — the loss of open space and the spread of invasive weeds — are exacerbated by motorized vehicles.

As it stands now, there is a confusing mishmash of regulations across the national forest system: Some forests, such as the Sulphur Ranger District of Arapaho National Forest, restrict riders to designated trails; others, such as the Black Hills National Forest, allow unrestricted cross-country riding. "In some forests, off-highway vehicle riders have the opportunity to go wherever they wish," says Sharon Metzler, off-highway vehicle lead for the Forest Service. "And the end result on the ground is not very pretty."

Under the proposed new rule, each forest will inventory its trails and roads, then gather public input to decide which of them should be open to motorized vehicles. Forest staffers will then create a map showing which trails are open to OHVs; copies of it will be available at ranger stations, trailhead kiosks, and ultimately, on the Internet. Most forests will rely on these travel maps to guide trail users, rather than putting up signs. "We’ve had a great deal of difficulty posting trails as either open or closed," says Metzler. "People who don’t like the posting just jerk the signs out."

OHV users are generally pleased but also wary about the proposed rule. "We’re prepared for some trails to be closed," says Brian Hawthorne, public-lands director of the BlueRibbon Coalition, an OHV advocacy group. "But if environmentalists take a hard-line position about motorized use, ranger districts will find themselves being litigated, and we’ll still get to go on the trails while the (designation) decision is tied up in some stupid lawsuit."

Environmentalists say the proposed rule, which would prohibit cross-country riding in most areas, is a step in the right direction, but falls short of protecting forests from abuse. "We feel that what they’ve come out with will be largely ineffective," says Aaron Clark of the Southern Rockies Conservation Alliance. Chief Bosworth has asked forest supervisors to complete the work within two to four years, but the Forest Service hasn’t asked Congress for additional funding for the inventory and mapping work — districts will just have to redistribute the money they already have. And as it is, the nation’s forests currently average only one law enforcement officer for every 450,000 acres, so enforcing any rules will be difficult.

On the Arapaho National Forest, Sedacca and his frustrated fellow property owners have started trying to rein in lawless riders themselves. On a recent Saturday afternoon, Sedacca watched a group of off-roaders drive onto a neighboring lot that’s up for sale. The riders tore in circles over and around the lot’s granite outcroppings, scarring the ground and crushing shrubs. Sedacca finally drove his own ATV over to the scene. "I asked them what they thought they were doing. They had absolutely nothing to say," he recalls.

But Sedacca and other citizen enforcers may face potential danger in getting involved: From Utah to California, trail users report that confrontations are becoming more and more common, and have even resulted in weapons being brandished by both sides.

"I stop at least one group of law-breaking riders every weekend. If we don’t do it, no one else will," says Sedacca. "You can pass any law you want, but some people will ignore it. It’s still the Wild West up here."

The author, a former intern, writes from Fort Collins, Colorado.

Public comment on the proposed rule will be accepted until Sept. 13 at www.fs.fed.us/recreation/programs/ohv