Smokejumpers Guide to Forest Fire Fighting

The Dragon Is Vulnerable

A baby dragon needs all three legs of a heat, fuel and
oxygen triangle to be born, grow, reproduce and spread.
Remove any leg of this triangle, and the dragon will slow
down and eventually die. Wildfire fighters often cool a
fire (or its fuel) by pouring water on it; we sometimes
starve a burn by clearing away fuel in its path; and at
times we’ll smother a minor blaze by beating it with damp
gunnysacks.

Besides the triangle that gives the dragon life, three
environmental factors affect its speed and strength:
weather, topography and the nature of the fuel.

Weather: This is the most important influence on
how a fire will prosper. In fact, weather actually makes
the time ripe for a fire to start by warming, drying and
fanning the fuel.

Wind is the most obvious element. It drives the fire
forward, dries out fuel and can actually carry firebrands
beyond the immediate burn causing new fires to develop.

Humidity is also important, especially when lightweight
fuels are present. Grass, lichen, moss and small twigs
absorb moisture from the air and so may be reluctant to
carry the dragon when the air is humid. Conversely, when
the air is dry, light fuels almost immediately become
tinder. Humidity can be a dominant factor in firefighting
tactics.

Temperature is important, but it’s a one-way street. That
is, the fire danger is usually greater on hot days, but
cold may not squelch a ferocious burn. I’ve fought fires in
Alaska in sub-zero temperatures when the humidity and winds
were the dominant factors. Likewise, summer isn’t the heavy
fire season in the eastern U.S. Spring and fall, when winds
blow and the humidity is low, bring the greatest number of
wildfires.

Sunlight isn’t usually mentioned as an important influence
on fires, but I’ve noticed that it has a lot to do with
light-fuel dryness in some situations. I’ve found that when
the weather is hot, sometimes only the vegetation in direct
sunlight will ignite. Also, in intense sunlight, a cloud
passing can change everything.

Topography: The lay of the land has much to do
with how a fire will behave. Slope, orientation and
elevation are the main influences.

The steeper the slope, the faster the dragon will run
uphill. Fuel upslope is heated by radiation and convection,
and it’s more accessible to the flames than fuel on flat
terrain. There’s also the chance that the beast will take
of downhill as chunks of burning material roll down.
Remember, wind isn’t the only thing that determines which
way a fire will spread. Slope is a major influence on a
fire’s behavior.

The direction the slope faces (its aspect) determines, in
part, how dry the vegetation will be. South- and
west-facing slopes are the driest; north-facing, the most
moist. This has become especially important as more and
more people turn their homes toward the sun for heating. A
solar home is almost automatically more vulnerable to fire
hazard and requires wise defensive preparation.

High elevation usually means lower fire danger, since it
normally offers cooler temperature, later snow melt and
more moist vegetation. However, unless you build in an
alpine zone, you probably won’t be nearly high enough to
have your altitude make much difference.

Fuel: Each ecosystem has different vegetation
characteristics. The most important of these are moisture
content, piece size, amount per acre, proximity of clumps
and horizontal and vertical distribution. Even the chemical
make-up of the fuel is important. Some woods have pitch,
and there may be flammable oils in leaves or needles.

We smokejumpers talk about wildfires as if we were looking
down on them from above — a parachutist’s-eye view.
Figure 1 (see the illustration in the image gallery) shows the dragon’s basic anatomy, describing it in a
common language that a group of firefighters could use to
discuss strategy and report their positions. Let’s go into
a little more detail about the parts.

Head: This is the main ball of heat, flames and
smoke at the front of the fire’s advance. It’s usually the
most difficult part of the fire to deal with. Sometimes a
wind change can blow the fire toward the tail or one of the
flanks, causing the head to relocate quickly.

Tail: The back of the fire is usually where it
started. On occasion, I’ve seen a fire burn against the
wind. This has happened on slopes with strong downhill
winds and on perfectly flat ground. We say the fire is
backing, and still call the downwind end the tail.

Left and right flanks: The sides of the fire may
have active flames, but they’re usually less intense than
those at the head. When the head is too hot to approach,
firefighters often try to attack the flanks. One flank will
generally be less smoky than the other and will be easier
to work on.

Flame length: The single most important physical
aspect of a fire is the height of the flames licking out
from the head. Flame length will determine how and where
you’ll do battle with the dragon. More often than not, you
don’t try to kill the dragon by cutting off its oxygen
or cooling it. You stop it by denying it fuel. To
do so, you clear a path all the way around the fire,
encircling it with a fuel-free line two to three feet wide.
The actual width and depth of the line depend on the types
of fuels present. In the West, we dig down all the way to
mineral soil with a Pulaski. But in eastern hardwood
forest, we only rake aside the leaves with a fire rake and
remove the underbrush.

Any fallen trees that bridge the line need to be cut. Use a
chain saw to remove a piece that’s as wide as the line or
twice as long as the tree’s diameter, whichever is greater.

Always attack the dragon from anchor points. These are
secured zones from which you begin digging line or beating
the flames. You may start at the head or tail of the fire
and have half the team move around each flank, or you may
split the team initially and work from two anchor points
— one on each flank at a natural barrier. The
important thing here is that the anchor point is
secure — a place where the fire can’t run
around the line and outflank you. Anchor points are vital
to success and safety. It also follows from this principle
that it takes a minimum of two people to best fight a
wildfire.

If the flame length is short — less than two feet
— you can make a direct attack on the
dragon’s head. When the fire is smoldering, creeping or
running along close to the ground, you can usually get up
close enough to clear a fuel-free path or actually beat out
the flames directly.

When the flames or smoke are a little too intense for you
to get close to the head, you can start at the tail and
work forward along the flanks. If at all possible, though,
go for the dragon’s head while it’s still vulnerable. Winds
could pick up while you’re working your way around the
flanks, and the head could gain intensity and speed.

If you’re unable to go straight for the dragon’s head or
tail, move out in front of the fire’s advance and set up an
ambush. In an indirect attack, you dig a line and
burn the fuel before the fire arrives. There’s no
substitute for experience in determining just how far ahead
to set the ambush. Lacking that, be sure to err on the side
of safety. Move out far enough to give yourself plenty of
time to burn out the line and still keep your people out of
the dragon’s reach.

Dig a line one to three feet wide, depending on the
flammability of the fuel and the size of the crew, moving
from the head around the flanks. As you go, have the last
person in the team burn out on the inside of the line,
closest to the fire. The intentional burn will
consume the fuel between the fire and the line, halting the
dragon’s advance.

Know your land and use natural barriers to help you make a
stand. Roads, streams, ponds, trails and other natural
features are great places to stop the dragon in its tracks.
Even a meadow is preferable to a heavily wooded area,
because it will be easier for the crew to clear the lighter
fuels from the fire’s path. In this area, at least, a
homeowner can have an advantage over a professional
smokejumper. The jumper may have the ability to compute
flame length, travel time, manpower and fuel types to
estimate what the fire might do. But the homeowner
knows where the natural barriers are without having to
reconnoiter.

Knowing When to Back Off

Flame lengths greater than about eight feet are considered
uncontrollable. Also, if there are ladder fuels lifting low
flames up into trees or if there are firebrands being
carried past you by the wind and starting spot fires,
you’re in over your head and are in danger. Back off! There
are few jobs more dangerous than fighting out-of-control
wildfires. Respect the dragon; it’s better to retreat and
have a chance to fight again another day.

Editor’s Note: Trooper Tom’s complete wildfire
fighting manual, From Dragon Slayers, is now
available. The roughly 60 page book discusses
tools, tactics and regional firefighting
techniques in much more detail than is possible
here. You can order a copy by sending $10 to
MOTHER’s Plans, Dragon Slayers, Hendersonville, NC.

Trooper Tom spends his summers as a smokejumper with
the Bureau of Land Management at Fort Wainwright, Alaska.
He winters in Oregon building houses and ponds. Troop’s
other publications include an article and a book on log
building, both of which were published by MOTHER EARTH
NEWS.

Firefighting Tools

Different regions of the country demand different
firefighting tools, but here’s a summary of the necessary
pieces of equipment, what each does and about what it
costs. Since your minimum team is two people, have at least
two rakes and two Pulaskies.

Fire rake: This is different from a traditional
garden rake. It has triangular tines that prevent it from
plugging up with leaves. Its main purpose is to scrape off
leaves or pine needles, and it’s used mainly on eastern
fires. About $25.

Pulaski. Half ax, half mattock, this is the
primary hand tool for digging line in western firefighting.
With it, you can chop out brush with the ax side and then
dig down to subsoil with the mattock. About $50.

Drip torch: An aluminum can full of a 50:50
mixture of gasoline and diesel fuel, the drip torch is the
tool for fighting fire with fire. It lays down a stream of
flame and is the best device for burning out large areas. A
Fuzee, a standard highway flare, will suffice for small
areas.

Backpack water pump: This common five-gallon
device — often used for distributing agricultural
chemicals — is great for wetting down fuels and for
mopping up small hot spots after fighting a fire. About
$100.

Chain saw: For woodland fires, you’ll need
something to section downed trees. I’ve been fond of my
Husqvarna 44 and my Homelite 925, but lately I’ve really
taken to Shindaiwa’s 695 — a 4.2-cubic-inch saw with
a 28-inch bar. Between $350 and $550.

Motorized pump: If you have any sort of body of
water — pool or pond — it’s worthwhile to have
a pump. You can use it to deliver water directly through
hose, or you can fill up a fiberglass holding tank in a
pickup and have your own miniature pumper. About $300.

Silv-ex: This foaming chemical increases water’s
ability to cool and penetrate. Used at the rate of a couple
of teaspoons per five gallons, it really boosts the
efficiency of a backpack water pump. You can also use it
with a motorized pump to do larger areas or even to foam
your house. About $100 per five gallons from Wajax-Pacific
Fire Equipment, Seattle, WA, or you
can order smaller quantities from me.

You can probably find most of this equipment at a local
dealer. If you run into trouble, though, I’m a dealer for
most of these items. Write me at Trooper Tom’s Fire
Protection Company, Manzanita, OR.