an uncontrolled fire on lands covered wholly or in part by timber, brush, grass, grain, or other flammable vegetation —see brush fire, grass fire, natural fire, wildfire, wildland fire situation analysis —note forest fires are defined as follows for legal purposes:

—crown fire a fire that advances across the tops of trees or shrubs more or less independently of the surface fire —note a crown fire is sometimes classed as running (independent or active) or dependent (passive) to distinguish its degree of independence from the surface fire

—finger a long, narrow extension of a fire projecting from the main body

—fire edge any part of the boundary of a fire at a specified moment

—flank that part of a fire's perimeter that is roughly parallel to the main direction of spread

—ground fire a fire that burns the organic material in the soil layer, such as peat or duff —synonym muck fire, organic soil fire, peat fire —see surface fire

—head that portion of a fire edge with the greatest rate of spread —note the head of a fire is generally leeward or upslope

—rear 1. the portion of a fire spreading directly into the wind or down slope 2. the portion of a fire edge opposite the head —synonym heel 3. the slowest spreading portion of a fire edge

—surface fire a fire that burns only surface fuels such as litter, loose debris, and small vegetation —see ground fire This definition last updated 10/24/2008