(CNN) Northern New Mexico's Philmont Scout Ranch, which has drawn generations of Boy Scouts who arduously train for its rugged trails and peaks, has canceled five weeks of backcountry treks because of a large wildfire.

Officials on Monday afternoon said they made the "difficult decision" to cancel treks and other activities that were scheduled for June 8 through July 14. Staff members who had been preparing for the hikers are making phone calls to affected crews, helping them to make new plans.

Approximately 13,000 registered youth and adults are affected, though some might be able to come later in the summer, said ranch spokesperson Shelley O'Neill.

"The safety of our youth participants, volunteers and staff is a priority for everybody at Philmont Scout Ranch and the Boy Scouts of America," the ranch said on its website . "While efforts continue to extinguish the fire currently burning in the backcountry, the anticipated damage and inability to access the affected areas makes it currently impossible to host backcountry programs."

"Until the fire is extinguished, the areas are inspected and the damage assessed, it is impossible to definitively state when those programs will resume," the statement said.

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