fire & the forest. terms wildfire-the uncontrolled burning of fire incendiary-the unlawful &...

FIRE & THE FOREST

TERMSWildfire-the uncontrolled burning of

fire

Incendiary-the unlawful & intentional setting of fire

Debris burning-burning of trash

Prevention-any action associated with stopping a wildfire before it is started

Pre-suppression-any action associated with being ready in case a wildfire occurs

Suppression-any action associated with stopping a wildfire

Prescribed burning-the controlled use of fire.

Origin-where a fire starts

Perimeter-the outmost area of the blaze including the head, flank & rear

Relative humidity-the amount of moisture in the air

Alidade-an instrument used in locating fires

Buildup index-a rating of the cumulative effect of drying since a rain of 1/10” or more; indicative of the intensity with which a fire can burn. Scale 1-100

Spread index-a relative rating of the forward movement of a fire; rated on a scale of 1-100

Wind velocity—the speed of the wind measured in miles per hour

Psychrometer—an instrument that measures temperature & relative humidity

Heavy fuels—contains a high percentage of thick material such as logs, large limb & tree tops

Medium fuels—contains light materials such as limbs & tree tops less than 4” in diameter

Light fuels—grass, leaves, small limbs & twigs

Duff—forest litter & other organic debris in various stages of decomposition on top of the mineral soil

Ignite—to burn or burst into flames

Mortality—death or destruction of forests due to fires

Fire Season—the period of the year which fires are likely to occur

Mixing height—height the smoke mixes with the wind, should be at least 1500 feet

Transport wind speed—speed of the wind at mixing height, should be at least 9 mph

Effects of Wildfires1. Destroy or reduce value of standing

timber

2. Destroy young seedlings

3. Reduce the growth rate

4. Reduce the water holding capacity of watershed & cause erosion

5. Pollute local streams & ponds

6. Kill or injure wildlife as well as the habitat

7. Encourage insects & disease in the stand

8. Can effect local & state economy

Causes of Wildfires65% of fires caused by:

40% escaped debris burning fires25% woods arson

Average size wildfire in the Southeast is 19 acres per fire

Ga. Average wildfire is 4.7 acres

Requirements for a Fire

1. Fuel-wood or other plant material

2. Oxygen-air is the main supply

3. Heat Source-sparks, lightning, cigarettes

A fire is like a 3-legged stool, remove one leg & the fire goes out

Types of Forest Fires

Ground Fire-fires that burn the organic materials beneath the surface litter of the forest floor

Surface Fire-fires that burn surface litter of loose debris on the forest floor & small vegetation

Crown Fires-fires that burn from top to top of trees or shrubs

Georgia Forestry Fire Laws

Criminal Damage to property in the first degree

1. Knowingly & without authority interferes with any property in a manner so as to endanger human life

2. Punishment of not less than 1 or more than 10 years

Criminal Damage to property in the second degree

1. Intentionally damages any property of another person without his consent & the damage exceeds $100

2. Punishment of imprisonment of not less than 1 or more than 5 years

Criminal Trespass1. Intentionally damaging property

of another without his consent & damage is less than $100

2. Punishment is a misdemeanor

Use of fires & ignited objects

It shall be unlawful:a. Start or cause a fire on any woodland

not one’s own or leased without owner’s permission

b. Burn without taking necessary precautions to prevent the escape of the fire

c. Cause a fire by discarding any burning object

d. Destroy or damage any material or device used in detection or suppression of wildfires

Notice of intention to burn Law

1. County forestry unit must be notified of time & location before setting fire to any combustible materials

2. Violation is a misdemeanor3. Must obtain a permit before

burning

Fire BehaviorFire is affected by a wide range of

conditions1. Air movement-both horizontal &

vertical movement of air as well as wind speed

2. Fire season-for Georgia is fall & spring of the year

3. Topography-slope of an area affects the rate of a fire, generally the steeper the slope the faster the fire

Weather conditions that reduce the rate of spread

1. Rain on the fire

2. Wind reversal

3. Increases in relative humidity

Types of fuelsThe two basic fuel types are:

Ground fuels-fuels found on the surface of the soil

Aerial fuels-fuels include all burnable materials located in the canopies above 6 feet from the ground

Fire ControlDivided into 2 main headings1. Prevention-things done to

prevent a fire from happening

2. Suppression-things done to stop a fire once it has begun

PreventionThe most effective & least expensive

method of controlPrevention Measures include:Clear all fuel back several feet from

trash, camp or warming firesNever leave fires unattendedHave suppression tools & methods

availableKeep fires small

Avoid burning during dry spells, windy days or when RH is low

Maintain fire equipment in safe running condition

Extinguish all matches & smokes before discarding

Use prescribed fires to reduce or eliminate fuel

Methods1. Be familiar with the property &

the best way to get equipment to each area under all conditions

2. Locate firebreaks & keep them maintained

Pre-suppression: Preparations made before a fire starts to more effectively control it.

3. Know your neighbors & ask them to report you on any unusual smoke in your area

4. Keep your fire fighting equipment in a handy, known location

5. Know how to contact the County Forest Ranger;

478-934-3124

Suppression: action necessary to extinguish a fire after it has started.

Basic jobs of fire suppression:1. Rob the fire of fuel

2. Reduce the fire’s temperature

3. Cut off the oxygen from the fire.

Major parts of a FireHead: the portion of the fire toward

which the air is moving; the fastest moving part of a fire

Rear: the portion of the fire which air is moving away; slowest part of a fire

Flank: the sides of the fire

Methods of attack in suppressing a fireDirect: fighting the fire at the head

of the flames. Used when the flames are not too intense & moving slowly.

Indirect: Used where heat & rate of spread will not permit a direct attack

Additional control methods

Mop-up: making sure that all fire & smoking material is out or safe inside the fire breaks.

Patrol: Periodic inspections made over the area until the fire is “dead out”

Beneficial Uses of Fire

1. Hazard Reduction-Reducing the forest litter & undergrowth

2. Hardwood Control-Hardwoods under 2” dbh can be controlled with fire. Summer burns give the best results

3. Site Preparation-the most economical tool to provide conditions for re-establishment of forests. Reduces competition & provides suitable seedbed.

4. Wildlife Habitat-Reduces predator cover, exposes hidden seeds & produces fresh low browse for wildlife.

5. Disease control-Only practical method of controlling Brown Spot Needle Blight. Burns away infected needles without killing the well protected bud. Litter reduction seems to reduce the incidence of Annosus Root Rot. No know control for this disease once established.

6. Improved Accessibility-Improves accessibility & visibility for marking & cruising timber. Also helps for harvesting operations. Can improve recreational & aesthetic values.

Prescribed (Prescription) Burning

The controlled use of fire in the forest to accomplish specific purposes

1. Most economical tool used for cleaning operations in young pine stands

2. Can be used for less than $3 per acre.

3. Should only be done by persons trained in its use.

Conditions to consider prior to prescribed burning

1. Relative humidity

2. Temperature

3. Wind, velocity & direction

4. Fuel moisture

Fuel Conditions

Refer to the amount & arrangement of the fuel, along with the desired intensity of the fire.

A continuous litter of needles or grass is usually needed

On well-stocked pine sites, fuels reach critical levels in about 5 years.

Low growing shrubs with pine straw can cause a level of aerial fuels which can create a great level of heat & should be considered when burning

Weather Factors

Temperature—20 to 60 degrees is the ideal range for winter burning; Hardwood control or site prep is often best accomplished in the summer with temperatures of 80 degrees or above.

Wind—Steady at 2-10 mph northerly is best. Steady wind direction & speed are vital for good burning.

Relative Humidity—30to 50% is the best range. A 20 degree rise in temperature can reduce the RH by half.

Rainfall—one half to one inch, one week before burning is recommended. For most prescribed burns the upper litter layer should be dry to the touch.

Season of the Year

Winter burns—offer the advantage of less stand damage, more predictable weather & steady winds

Summer burns—offer hotter fires to burn more of the rough for seed bed & site preparation

Time of Day

Day time fires offer better weather conditions. Burns should start about 10 a.m. & stopped so to burn out by night.

Night fires have problems with light winds & higher humidity

Types of Fires

Head fire

Backfire

Strip Head Fire

Flank Fire

Head Fire

Fires moving in the same direction of the wind.

Generate the most heat & travel at the fastest rate.

Good fire for site prep fires

Backfire

Fire moving in the opposite direction to the wind. (Burning into the wind)

Steady 4-10 mph wind

Generally burn at 100 feet per hour

Well suited for sapling size stands & plantations 15’ or more in height

Strip Head Fire

Used in conjunction with backfires

Only 75-100’ wide

Winds should be 2-5 mph

Used to burn large areas much faster

Flank Fire

A supplemental burning technique

A fire set into the wind that burns at right angles to the wind

Used to even up backfires & strip head fires

Burning Interval

The amount of time between burns

Usually every 2-5 years

Dependent on available fuel

Planning a Prescribed Burn

Select areas to be burned

Select burning method to use

Locate & scout firebreaks

Determine smoke sensitive areas

Smoke Sensitive Areas

AirportsHighwaysCommunitiesResorts or Recreation AreasSchoolsHospitalsFactoriesStockyard or holding pens

Conducting a Successful Prescribed Burn

Get weather forecast & observe conditions prior to burning

Notify adjoining landownersObtain a permit to burnStart with a small test fireSet backfires as close as possible to

firebreaks

Fire only as many lines as you have manpower to watch

Watch for changing wind conditions

Watch for burning snags & stumps near firebreaks

Mop-up smoldering materials along firebreaks

Evaluating the Burn

Check for crown scorch—if 1/3 or less of the crowns are discolored in a winter burn, there is little or no damage

Trunks should not be blackened over 3’ high, if so, the fire was probably too hot