TexasCreekFire_MarcyP

Part of the Carlton Complex Fire burned in the Texas Creek area on July 15. Here trees can be seen torching. File photo by Marcy Stamper

Compiled by Marcy Stamper

This glossary includes standard terminology as well as colloquial terms that often appear in updates on fire status.

Parts of a fire

fingers of a fire: long, narrow extensions projecting from the main body

flank of a fire: the part of the perimeter roughly parallel to the main direction of spread

head of a fire: the side of the fire with the fastest rate of spread; also called leading edge

island: an area of unburned fuel within the perimeter

perimeter: the entire outer edge of a fire

point of origin: the precise location where the fire first ignited

rear of a fire: the slowest-spreading portion of a fire, generally heading into the wind or downslope; also called heel

spot fire: fire ignited outside the perimeter

Fire behavior

backing fire: the slower-moving part of the fire, generally moving into the wind or downslope

blow-up: an acceleration or intensification significant enough to change fire-control plans; compare flare-up

convection column: rising column of gases, smoke and other debris produced by a fire

creeping: fire burning with a low flame and spreading slowly; also called skunking

crown fire: a fire that moves from the top of one tree or shrub to another; which can move independently of the fire activity on the ground

dirty burn: an area where there is still a lot of standing, half-burned fuel susceptible to reburning

flare-up: a brief acceleration or intensification of fire that does not change fire-control plans; compare blow-up

hot spot: a particularly active part of a fire

plume-dominated fire: fire with behavior dominated by the convection column that can spread in any direction because the fire will pull burning debris into the column and spit it out anywhere

running: fire that is spreading rapidly with a well-defined head

skunking: fire burning with a low flame and spreading slowly; also called creeping

sleeper fire: fire started by lightning strikes that go underground and erupt several days or weeks later from wind or hot, dry conditions; also called holdover fire

a smoke: evidence of a new fire, often after a lightning strike (colloquial)

smoldering: fire burning without flame and barely spreading

spotting: starting new fires outside the perimeter by sparks or embers carried by the wind

torching: burning of foliage of a tree or small group of trees from the bottom up; depending on the number of trees involved, may be described as single or group torching

Control and suppression

anchor point: a barrier from which to start building a fire line

burnout: a tactic that involves burning the area between an established control line some distance from the fire and the main fire; sometimes called backburn or backfire, but the official term is burnout

containment: a control line completed around the fire and associated spot fires that can be expected to stop the fire from spreading

control line: an inclusive term for all constructed or natural barriers used to contain a fire

control: completion of a control line around the perimeter, spot fires and interior islands; burnout of unburned areas adjacent to the control lines; cooling of all hot spots

coyote tactics: use of spike camps; also called coyoting

direct attack: establishing a control line on the perimeter of the fire by digging down to mineral soil

fire line: a control line scraped or dug to mineral soil; there are hand lines (dug with shovels) and dozer lines (dug by bulldozers)

firing operations: setting prescribed fire or burnouts using drip torches or aerial ignition

hot shots: highly trained fire crews used mainly to build fire line by hand, often in rugged terrain

indirect attack: establishing a control line some distance from the main fire, either by digging a line or using a natural barrier such as a road or river

management action points: geographic points on the ground or specific points in time that guide fire management; also called trigger points

mop-up: extinguishing or removing burning material near control lines and felling snags to make an area safe after it has burned

patrol status: going back and forth over a control line to suppress spot fires and extinguish hot spots

point protection: specific structures or communities identified for protection

spike camp: where firefighters stay to work on a fire when it is far from roads or involves a long hike; a line spike camp refers to a camp on the fire line

Fuels

jack-strawed trees: trees scattered like toothpicks, generally from a windstorm

ladder fuels: surface fuels such as needles or leaves, and shrubs and lower branches that provide a path for the fire to move from the ground to the tree canopy

light, flashy fuels: dry grasses and shrubs

Weather

Haines index: measures the stability and dryness of the air over the fire to indicate the potential for wildfire growth; the index ranges from 2 to 6—the drier and more unstable the lower atmosphere is, the higher the number

Other terms

defensible space: an area around a house cleared of flammable vegetation and other potential ignition sources and kept well-maintained and watered

Sources: National Wildfire Coordinating Group Glossary of Wildland Fire Terminology, a glossary on WildlandFire.com, and interviews with public information officers from the incident management teams and local firefighters.