CASTLE DALE, Utah -- Calves forced over a ledge. Deep, wide ruts in sensitive roads. Trucks racing to explore for gas and coal.

They represent an unprecedented use of vehicles in Emery County, which is warning about the consequences.

The county's Public Lands Council recently issued a statement that calls for tough enforcement and more education on the proper use of land.

"There will continue to be conflicts between users. ... Those who are prone to non-compliance need to know that federal agencies, local government and other users won't accept their behavior," the council said.

Environmental groups welcomed the statement, especially since counties in central and southern Utah often have clashed with the federal government over access.

"They're breaking trail here, no pun intended, and I think it will have positive results," says Heidi McIntosh, conservation director for the Southern Utah Wilderness Alliance.

"Other counties can't help but look at this as a good example to follow. They're all dealing with the same issues," she said.

Utah's off-highway vehicle registrations have tripled since 1998 to over 200,000, putting increased pressure on the backcountry.

Emery County has become a popular destination for OHV enthusiasts, thanks to a diversity of terrain that includes the rugged desert canyons of the San Rafael Swell and dense forests on the Wasatch Plateau.

Thirty years ago, the council noted, a pickup truck was a typical vehicle. Now, sedans are on the same roads.

"We want to see resource development. We welcome (OHV) users. But that doesn't mean we want unrestricted use," said Ray Peterson, the county's public-lands director.

There have been conflicts between livestock and vehicles. Two calves recently were pushed over a ledge by an impatient motorist, suffered broken legs and had to be killed, the council reported.

"We know there are counties that have really disagreed with what we've done, but that's all right," Peterson said of the council's statement. "We've tried to stay on top of this and make wise decisions."

Mike Swenson, executive director of an OHV group, the Utah Shared Access Alliance, supports cracking down on the "few bad apples that are creating the problem."

"But we would also oppose solutions that are so restrictive that they impact other users," he said.

This story appeared in The Daily Herald on page D2.