Wildland Handbook, Chapter 4

Flame length of 4 to 8 feet

Fire are too intense for direct attack on the head with hand tools. Handline cannot be relied upon to hold the fire. Bulldozers, engines and retardant drops can be effective

Torching

Fire burning on the surface, but periodically igniting the crown of a single or small group of trees or shrubs before returning to the surface. Although sometimes confused with crowning this behavior is not as serious as a crown fire.

Creeping

Fire burning with low flame and spreading slowly

Backing

Fire moving away from the head, downhill or against the wind

Running

Fire spreading rapidly with a well defined head

Crowning

Fire that advances across tops of trees or shrubs more or less independent of surface fire, High fire intensity and high forward rate of spread.

Flame length less than 4 feet

Fires can generally be attacked at the head or flanks by firefighters using hand tools. Handline should hold fire

Flame length of 8 to 11 feet

Fires may present serious control problems: torching, crowning, and spotting. Control efforts at the head will probably be ineffective

Spotting

Sparks or embers produced by the main fire are carried by winds or convection column.

Blowup

Sudden increase in fire intensity or rate of spread sufficient to preclude direct control or to upset existing suppression plans

Spread

The movement of the fire, usually measured by its rate.

Smoldering

Burning without flame, spreading very slowly

Flame length over 11 feet.

Crowning, spotting and major fire runs are probable. Control efforts at the head of the fire are ineffective

Wildland Fire influencers

Fuel, Weather, Topography