Prescribed Fire

Prescribed fire in Yellowstone means not only controlled burns used to meet management objectives, but also includes natural fires ignited by lightning that fall within a "prescription" that are allowed to burn as an ecosystem process. A prescription is a set of conditions that considers the safety of the public and fire staff, weather, and probability of meeting the burn objectives. Natural ignitions are sometimes called prescribed natural fires (PNF), "fire-use fires" or "Wooferb" fires (WFURB=Wildland Fire Use For Resource Benefit).

Since 1972 much of the park has been designated a "Natural Fire Zone" in which natural ignitions are monitored closely but allowed to burn as a natural process without intervention. In the last thirty years over 300 lightning-caused fires have been allowed to burn and die naturally in Yellowstone.

Compared with other agencies and parks, there have been relatively few management ignited prescribed fires in Yellowstone. Historically prescribed burns have been ignited to reduce hazardous fuel loads near developed areas, and for research purposes. Currently we have several prescribed burn plans which may be implemented in the next few years but most hazard fuel reduction is accomplished with saws and manual removal. See the Hazard Fuels Management Plan (1.9m pdf file) for more details.

Hazard fuel reduction around the park's developed areas provides for fire fighter safety and structure protection in the event of a wildfire, but also gives the fire management staff greater confidence and a broader prescription to allow natural ignitions to burn their course.