IGNITION: Fuels do not ignite readily from small firebrands although a more intense heat source, such as lightning, may start fires in duff or dry rotted wood.

SPREAD: Fires in open cured grasslands may burn freely a few hours after rain, but woods fires spread slowly by creeping or smoldering, and burn in irregular fingers.

SPOTTING: There is little danger of spotting.

CONTROL: Easy

IGNITION: Fires can start from most accidental causes, but with the exception of lightning fires in some areas, the number of starts is generally low.

SPREAD: Fires in open cured grasslands will burn briskly and spread rapidly on windy days. Timber fires spread slowly to moderately fast. The average fire is of moderate intensity, although heavy concentrations of fuel, especially draped fuel, may burn hot.

SPOTTING: Short-distance spotting may occur, but is not persistent.

CONTROL: Fires are not likely to become serious and control is relatively easy.

IGNITION: All fine dead fuels ignite readily and fires start easily from most causes. Unattended brush and campfires are likely to escape.

SPREAD: Fires spread rapidly. High-intensity burning may develop on slopes or in concentrations of fine fuels.

SPOTTING: Short-distance spotting is common.

CONTROL: Fires may become serious and their control difficult unless they are attacked successfully while small.

IGNITION: Fires start easily from all causes.

SPREAD: Immediately after ignition, spread rapidly and increase quickly in intensity. Fires burning in light fuels may quickly develop high intensity characteristics such as long-distance spotting and fire whirlwinds when they burn into heavier fuels.

SPOTTING: Spot fires are a constant danger; long distance spotting likely.

CONTROL: Fires may become serious and their control difficult unless they are attacked successfully while small.

IGNITION: Fires start quickly and burn intensely. All fires are potentially serious.

SPREAD: Furious spread likely, along with intense burning. Development into high intensity burning will usually be faster and occur from smaller fires than in the very high fire danger class.

SPOTTING: Spot fires are a constant danger; long distance spotting occurs easily.

CONTROL: Direct attack is rarely possible and may be dangerous except immediately after ignition. Fires that develop headway in heavy slash or in conifer stands may be unmanageable while the extreme burning condition lasts. Under these conditions the only effective and safe control action is on the flanks until the weather changes or the fuel supply lessens.