An escape fire is a fire lit to clear an area of vegetation in the face of an approaching wildfire when no escape exists. Unlike backfires, escape fires are not attempts to control – let alone stop – a wildfire. Like a backfire, it works by depriving an approaching primary fire of fuel so that when the primary fire reaches where the escape fire started the primary fire cannot continue; there is nothing there to burn.
The technique had been described in James Fenimore Cooper's 1827 novel The Prairie but became well-known only after the Mann Gulch fire. On this occasion, (Robert) Wagner "Wag" Dodge came up with the same idea independently, and successfully put it into practice. He cleared an area large enough for him to survive unharmed when the main fire was less than one minute away.
Escape fires are an option in grassland but do not work in forest fires because timber burns too slowly to consume the fuel before the main fire arrives.