List equipment and
personnel needed on site and on standby. Assign duties.
Fire
Prescription
The amount of fuel, weather conditions and
desired intensity of the burn will determine the firing technique and ignition pattern to
use. Species involved and height of overstory will determine the maximum intensity that can be
tolerated. Where large amounts of fuel are
present, cooler burns can be accomplished by burning when humidity and fuel moisture
are near the high end of the range so a smaller fraction of the fuel will burn. Lower temperatures
are desirable with more intense fires,
especially when understory fuels are tall.
A series of user-friendly
computer programs called BEHAVE has been developed to predict the behavior
of a fire. They are based on a specific set of fuel data and
prescribed weather conditions. These programs will run on a hand-held calculator with
a fire behavior CROM (Custom Read Only Memory). You can use them in the field to make
instant decisions as burning conditions change. A version
called MICRO BEHAVE, compatible with IBM PCs, is also available
at very low cost from Forest Resources Systems Institute (FORS), Courtview Towers, Suite 24,
201 N. Pine Street, Florence, AL 35630; telephone (205)
767-0250.
Always think about smoke management.
Make sure your burning plan passes a smoke management system.
Season
Winter - Most understory burning is
done during
the winter dormant season. Acceptable relative humidity, temperature, fuel moisture,
and steady, persistent winds most often occur then.
Spring -
More variable weather and generally higher fire danger
dictate smaller burns in the spring. Check with local wildlife specialists to avoid
periods when prescribed burning could harm nesting wildlife. Pine buds are more exposed and
thus more susceptible to heat damage during elongation.
Summer - Hot weather during the summer means
much less heat is needed to raise the temperature of plant tissue to lethal levels. For this reason,
summer burns are used to kill undesirable hardwoods -
usually a series of burns after an initial winter burn. Care must be taken not to severely
scorch overstory crowns. Postharvest burns to dispose of logging debris can be conducted
year-round, but conditions are especially good in
mid to late summer because the high ambient temperatures help dry out the larger
materials.
Fall - Exercise special care when burning in early
fall just prior to the dormant season. Both loblolly and
slash pines are more likely to die if severely scorched or root damaged at this time.
Time of Day
Normally, plan burning
operations so the entire job can be completed within a standard
workday. Prescribed fires usually are ignited between 10 a.m. and noon, after sunshine
has evaporated any early morning dew. If an inversion occurred the previous night, wait until
daytime heating eliminates it before igniting the
fire. If the forecast is for poor nighttime dispersion, halt ground ignition before 3 p.m.
standard time (ST). Halt aerial ignition before 4 p.m. ST, to allow adequate time for the fire to
burn out before atmospheric dispersion
conditions deteriorate.
Burning conditions are usually better during
the day than at night because windspeed is higher and wind direction steadier. Smoke
management is also much easier during the day. At night smoke
tends to stay close to the ground and collect in depressions. Also, relative humidity
usually increases at night, resulting in spotty burning and an increased likelihood that fog will
form.
However, on winter nights
when a strong cold front moves across an area, winds remain strong and persistent and
relative humidity does not rise greatly. These conditions can provide good prescribed burning
weather, especially when cooler temperatures are
needed. Whenever night burning is done, keep a close check on wind, humidity, and
smoke drift.
Firing Plan
Key parts of a
successful prescribed burn are plans for firing and holding a burn.
This plan should consist of a narrative section and a detailed map. The burning unit
map is ideal for this purpose because it already contains much pertinent information. Add the
following items:
- Firing technique, ignition pattern, and planned ignition time.
- Manpower and equipment needed, and planned distribution for setting, holding,
patrolling, and mopping up the fire and managing the smoke.
- Location and number of reinforcements and equipment that can be mobilized
rapidly if fire escapes.
- Instructions for all supervisory personnel, including complete description or
illustration of assignment, and forces needed to fire out, hold, and mopup the fire.
Alternative Prescriptions
Consider alternative sets of weather conditions (wind, relative humidity, and/or
fuel moisture) and methods of burning that will produce a fire of about the same
intensity and accomplish the desired objectives. Two separate burns may be necessary
to eliminate heavy volumes of fuel without damage to the overstory.
Preparation Work and Protection of Sensitive Features
Include fire lines to be constructed, snags to be lined or felled,
special features to be protected and the installation of any monitoring equipment. Give
instructions for the protection of sensitive areas.
Consider historical and archeological sites, streams, habitats of threatened and
endangered species, and fragile soils.
Notification of Intent to
Burn
List the names and telephone numbers of
the local State fire protection officer and other officials who should be contacted prior
to the burn. Make direct contact with all homes and businesses in the area likely to be impacted
by the burn. Offer to evacuate anyone with
respiratory problems during the burn. Put them up in a local motel if necessary.
Consider written notification explaining the reasons for the burn and encouraging individuals
with respiratory ailments to contact you - include a 24
hour telephone number. Establish responsibility for burn-day contacts and how they
will be made. Consider a newspaper article describing the reasons for the burn if you expect to
produce lots of smoke or anticipate any negative
reactions.
Establish Burn Acreage Goals But NOT Quotas!
Impact of Smoke
List any sensitive areas near to,
downwind, or down drainage of the burn. Include smoke management
strategies of avoidance, emission reduction, dispersal, or all three, to minimize any
adverse smoke impacts. Attach the smoke management plan (e.g. screening system calculations)
as part of the burning plan.
Legal Requirements
List any legal requirements that might
apply, and what the prescribed burner must do to comply. Remember, the person who conducts
the prescribed burning operation may not be the one who made
the analysis and prepared the prescription. Follow all applicable statutes, regulations,
and agency procedures. Needs for a written prescribed burning plan, documentation of deviations
from the plan, and good judgement cannot be
overemphasized. Erroneous forecasts, unforeseen local influences, and accidents occur
despite our best efforts to prevent them. Proper documentation will help establish that the
prescribed fire was conducted in a prudent and
professional manner. If a prescribed fire results in damage or bodily harm and you cut
comers, neglected any mandatory requirements, or acted with disregard to the welfare of others,
you are likely to be held responsible,
regardless of whether compliance would have changed the outcome. For more
information see the summary article, Legal Implications of Prescribed Burning in the
South by William C. Seigal, listed in the Suggested
Reading section.
Escaped-Fire Plan
Identify potential fire escapes and specify actions to take should such occur.
Designate who will be in charge of suppression action and what personnel and
equipment will be available.
Control and
Mopup
A plan must include necessary safeguards to confine the fire
to the prescribed area and reduce smoke impact. Mopup promptly and completely.
Emphasize protection of all adjacent land. Consider and make plans for any variation
in forecasted weather that may change a prescribed fire into a damaging wildfire, increase the
pollution in smoke-sensitive areas, or create
visibility problems on adjacent roads.
Evaluation
Include space for a written
evaluation of the prescribed burn. A record of actual weather conditions, behavior of the fire, and
total
environmental effects of the burn is essential. This information is used to determine the
effectiveness of the prescribed burn and in setting criteria for future burns.
At
the beginning of the prescribed burn, record
windspeed and direction, fuel moisture, humidity, burning index, temperature, days
since and amount of last rain, and dampness of soil and lower litter. Also record fire behavior
data such as type of fire used, length of flames,
and forward rate of spread. Continue to record applicable weather and fire-behavior
parameters at 2- to 3-hour intervals throughout the burn. After the burn, record amount of crown
scorch, consumption of brush, litter; and duff,
and any other evidence of fire intensity such as unburned areas, exposed mineral soil,
and cracks in bark or cupping on the lower bole due to bark consumption. Also include a short
narrative on success of the burn.
Prescribed Fires Often Behave Erratically At Edges Of Openings
Give Prescribed Burning FIRST Priority when Weather Conditions Are
Favorable
