Fire Danger Rating and
|Fuels do not ignite readily from small
firebrands although a more intense heat source, such as lightning,
may start fires in duff or punky wood. Fires in open cured
grasslands may bum freely a few hours after rain, but woods fires
spread slowly by creeping or smoldering, and burn in irregular
fingers. There is little danger of spotting.
(Light Green or Blue)
|Fires can start from most accidental
causes, but with the exception of lightning fires in some areas,
the number of starts is generally low. 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. Short-distance spotting may
occur, but is not persistent. Fires are not likely to become
serious and control is relatively easy.
|All fine dead fuels ignite readily and
fires start easily from most causes. Unattended brush and campfires
are likely to escape. Fires spread rapidly and short-distance
spotting is common. High-intensity burning may develop on slopes or
in concentrations of fine fuels. Fires may become serious and their
control difficult unless they are attacked successfully while
Very High (VH)
|Fires start easily from all causes and,
immediately after ignition, spread rapidly and increase quickly in
intensity. Spot fires are a constant danger. Fires burning in light
fuels may quickly develop high intensity characteristics such as
long-distance spotting and fire whirlwinds when they burn into
|Fires start quickly, spread
furiously, and burn intensely. All fires are potentially serious.
Development into high intensity burning will usually be faster and
occur from smaller fires than in the very high fire danger class.
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.