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Potential for fires in the South The Deep South is currently experiencing severe drought conditions and forecasters do not paint a pretty picture for this fall and winter seasons. The Georgia Forestry Commis-sion is very concerned with, not only potential deadly wildfires, but prescribed burners not fully educated on the effects prolonged droughts have on fuels and the soil. As wildland firefighters, we utilize several information outlets to properly staff units and prepare/modify work plans on critical fire danger days. One of the most common outlets is the National Fire Danger Rating System. Remote automated weather stations are located throughout Georgia for the purpose of gathering daily weather observations. These observations are used to calculate and create indexes, such as spread component, burning index, ignition component and drought index. The Georgia Forestry Commission uses the burning index for staffing levels for county units, which are labeled class days (1 thru 5) for firefighters. The general public receives similar warnings that coincide with those class days. An example would be: class one day for firefighters would be classified as a low fire danger day and class five would be extreme danger. One of the more important indexes that is very useful is the Keeth-Byram Drought Index. This index evaluates the effects of longterm drying on litter and duff. It is based on a measurement of eight inches of available moisture in the upper soil layers. The measure is in hundredths of an inch of water and has a range of 0 through 800, 0 being saturated and 800 the worse drought condition. Example: A KBDI of 300 would indicate a deficit of 3.0 inches of ground water available for vegetation. The KBDI is a very useful tool for the potential burner. The KBDI will tell you what to expect from a planned burn and what potential damages can result from a burn. The following chart will assist you in determining your best avenue. KBDI Level Conditions/Cautions 0-150 Fuels/grounds are moist, ideal for winter or spring burns, heavy fuels don't burn 150-300 Pine/hardwood stumps ignite but seldom burn below surface, heavy fuels resist burning, fire behavior predictable 300-500 Burn consumes most surface litter, significant loss in organic material, heavy fuels/stumps ignite readily and consumed, escaped fire difficult to control 500-700 All surface litter and most of organic material lost, dead snags ignite, dead limbs on trees ignite from sparks, stumps burn to end of roots, excessive site damage 700 + Many understory species contribute to fire activity acting as ladder fuels, extreme fire behavior, escape fires may become major problem, burning should be banned. On Nov. 14, the KBDI for the Camilla District was 492. I would strongly advise against understory burning with this KBDI because root damage can occur. Damaged feeder roots can lead to problems with insect and disease for years to come. Even though moisture recovery occurs nightly in the south, it mainly affects the lighter, grassy type fuels. Don't be fooled by two inches of rain in one hour. One inch of rain over the span of six hours will have more of an affect on the KBDI than a lot of rain in short period.
In summary, utilize all the information available to you to make an informed decision about burning. Go to the commission's web site, www.gatrees.org, to find the fire danger ratings, weather forecasts and other very useful information. Talk to your county ranger or forester for professional advice.
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