CHEYENNE, Wyo. - Large-group treks over the Mormon Pioneer and Oregon trails in central Wyoming will be curtailed to reduce environmental damage, federal land managers announced Monday.

The decision will most affect members of The Church of Jesus Christ of Latter-day Saints, who often re-enact the western journeys their ancestors made during the 19th century. Groups of as many as 400 sometimes dress in period clothing and pull belongings in handcarts along the trail.

Under the new rule, a maximum of 200 people would be allowed in one group, and those large groups would have to apply for and agree to conditions of a special recreation permit.

"We haven't decided at this point if we're going to sign the permit," said Lloyd Larsen, a Lander resident and spokesman for the church in Wyoming.

"They have given us the conditions of the permit and

we're studying them at this time and we'll make a decision

on what we'll do in the near future."

Larsen appreciates efforts by BLM personnel to gather public opinion and attempt to reach a fair balance, but said church officials are concerned about added responsibilities the church would face under the permit.

Interest by LDS members in retracing the trail was heightened in 1997 by celebrations of the 150th anniversary of the first trek to Utah made by church pioneers.

That interest has continued almost unabated, prompting the new rules.

The requirement of permits by large groups seeking to use a 20-mile public segment of the immigrant trails begins this year, said Jack Kelly, manager of the BLM Lander Field Office. A fee of $4 per person per day will be charged.

Comments received on the agency's environmental assessment from the church, as well as other interested groups and governmental agencies, were particularly helpful in making the decision, Kelly said.

"This decision provides for levels of use that will sustain the character and values of the National Historic Trails," he said in a release.

"It also protects wildlife, historic and cultural resources and provides a balance between church-sponsored handcart treks and other recreational uses of the area."

Limits will be phased in beginning in 2006.

A maximum of 7,500 people will be allowed to take part in activities between Sixth Crossing and Rock Creek Hollow, with 5,000 of the 7,500 allocated to the Farm Management Co., a subsidiary of the church.

Use will be allowed from July 1 through Sept. 15.

A two-mile section of the historic trails over Rocky Ridge will be closed to motor vehicles, to protect historical and environmental resources, Kelly said.

Individual and small-group use of the segment will continue to be exempt from permit and fee requirements.

Funds collected will be used by the Lander BLM office to manage the trails, which

have seen their use increase tenfold since the mid-1990s, Kelly said.

"We have a responsibility to make changes to curtail the impacts and ensure that the quality of the trail resources is maintained," he said.

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