An illegal logging operation that caused substantial damage was discovered in January on Canyons of the Ancients National Monument.
Monument manager Marietta Eaton said the violation occurred near the Utah border north of County Road 10. Citations were issued, but no names have been released.
"It has been so dry, they were able to drive in and cut or pull down more than 20 juniper trees," Eaton said. "Then they returned a second time to buck it up."
Wood cutting and collection aren't allowed in the monument.
Three people were given summons to appear in U.S. District Court in Durango on March 6.
Eaton said about 1.5 miles of off-road damage will to be rehabilitated.
Eaton said there are no cultural resources in the area.
BLM law enforcement officer Logan Briscoe, who issued the citations, said the investigation is continuing.
"It came to our attention on January 16, and on January 24 we caught the individuals," Briscoe said. "We've been having a problem with illegal wood cutting along County Road 10."
The illegal harvest is one of the largest officials have seen.
"Wood collection was shut down on the monument because typically you have to drive off-road to get to a tree, and that creates a lot of potential for damage to cultural sites," Briscoe said.
The individuals used a truck and an ATV to access and move the trees, according to court documents. They accessed the area via a two-track road that officials will landscape to hide it from County Road 10. It will be signed as non-motorized use only.
"It comes at a cost to the taxpayer, because the area has to be rehabilitated where the tracks caused damage, and that takes time and money," Briscoe said.