Following is a section of the Forest Service policy statement:
2326.1 – Conditions Under Which Use May Be Approved Allow the use of motorized equipment or mechanical transport only for: 1. Emergencies where the situation involves an inescapable urgency and temporary need for speed beyond that available by primitive means. Categories include fire suppression, health and safety, law enforcement involving serious crime or fugitive pursuit, removal of deceased persons, and aircraft accident investigations. 2. Aircraft or motorboat use established before the area was designated as wilderness by the Act of 1964 or subsequent wilderness legislation. 3. Exploration and development of valid existing mineral rights (FSM 2323.7). 4. Access to surrounded State and private lands and valid occupancies (FSM 2326.13). 5. To meet minimum needs for protection and administration of the area as wilderness, only as follows: a. A delivery or application problem necessary to meet wilderness objectives cannot be resolved within reason through the use of nonmotorized methods. b. An essential activity is impossible to accomplish by nonmotorized means because of such factors as time or season limitations, safety, or other material restrictions. WO AMENDMENT 2300-2007-1 EFFECTIVE DATE: 01/22/2007 DURATION: This amendment is effective until superseded or removed. 2320 Page 54 of 55 FSM 2300 – RECREATION, WILDERNESS, AND RELATED RESOURCE MANAGEMENT CHAPTER 2320 – WILDERNESS MANAGEMENT c. A necessary and continuing program was established around the use of motorized equipment before the unit became a part of the National Wilderness Preservation System, and the continued use of motorized equipment is essential to continuation of the program. d. Removal of aircraft wreckage when nonmotorized methods are unsuitable. Specify, for each wilderness, the places and circumstances in which motorized equipment, mechanical transport, or aircraft are necessary for protection and administration of the wilderness and its resources in the forest plan. The Line Officer approving the use of motorized equipment, aircraft, or mechanical transport shall specify what uses of that equipment are suitable and will have the least lasting impact to the wilderness resource. Schedule use of this equipment to minimize impact on wilderness visitors.
As stated in other blogs, the Forest Service Policy clearly allows use of chainsaws by exception. Wally Kimball