CRESTED BUTTE, Colo. — U.S. Forest Service agents have scoured Crested Butte’s ski area in search of illegal “smoke shacks” after some skiers were busted for smoking pot in one of the shacks on Feb. 17, according to a report in the Crested Butte News.

The shacks, from simple lean-tos to fully enclosed treehouses, are illegal structures, built on public land without permission.

“I’m sure we’ve got a few… I know they’re probably all over just about every ski area in Colorado,” Crested Butte Mountain Resort Vice President Ken Stone told the town’s newspaper last week.

In fact, just last spring, a Forest Service official ordered smoke shacks at Snowmass to be taken down.

“It’s becoming an issue all over the place,” Jim Stark, winter sports administrator for the White River National Forest, told The Aspen Times at the time.

The Forest Service is concerned about the extent of the structures at Crested Butte, the Crested Butte News reported.

“Forest Service law enforcement approached us about going into national forest on the ski area and having a look around. Obviously they knew there were some structures out there that were problematic and they don’t like them,” said Crested Butte mountain manager Jack Gibbons, according to the News article, written by Evan Dawson.

Inspecting ski areas for illegal structures is a routine procedure, Forest Service patrol captain Dan Nielsen told the News. “We’ve worked with the other resorts and found similar structures.”

The structures pose several problems, Nielson explained in the newspaper report. They can create hazards for unsuspecting skiers and often result in tree damage in the immediate vicinity. Damaged trees can lead to a bark beetle infestation, he said.

No information was available at the number of skiers, or snowboarders, who received a summons to appear in court for the marijuana infraction.