(AP) — The U.S. Forest Service says the deadline to take advantage of free firewood permits is approaching fast.

The permit program for the Pine Ridge Ranger District is set to expire on Dec. 31. Permit holders can harvest up to four cords of wood from Forest Service lands, up to 150 feet away from county and Forest Service Roads. One cord of firewood is measured as 4 feet by 4 feet by 8 feet.

Applicants must pick up their permits at the Pine Ridge Ranger District office. The permits be kept with the person when retrieving firewood.

John Lee, a district forester, says the permits will return to their regular $20 price on Jan. 1.