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exposure to the structure . The chances of ignition increase as the size of the flames
<br /> increases , surface area exposed to flames increases , length of exposure time increases , and
<br /> distance between the structure and the flames decreases . Ignition of a structure by
<br /> convection requires the flame to come in contact with the structure . Contact with the
<br /> convection column is generally not hot enough to ignite a structure . Clearing to prevent
<br /> flame contact with the structure must include any materials capable of produc ng even small
<br /> flames . Wind will tilt the flame and the convection column uphill , increasing the chance of
<br /> igniting a structure . Firebrands also pose a threat to structures in the Wildlan / Urban
<br /> Interface zone . A firebrand is a piece of burning material that detaches from a fire due to
<br /> strong convection drafts in the burning area . They can be carried a long distance (around
<br /> 1 mile ) by fire drafts and winds . The chance of these firebrands igniting a structure depends
<br /> on the size of the firebrand , how long it burns after contact , and the materials , design , and
<br /> construction of the structure .
<br /> Some plant and animal communities in south central Florida have ome to
<br /> depend on frequent lightning - ignited wildland fires for their continued existence . Many
<br /> threatened and endangered species depend on the periodic burning of dense scrub . Fire
<br /> suppression and landscape fragmentation have disrupted this natural cycle , but a long -term
<br /> policy of prescribed burns might help restore balance to the system .
<br /> The Division of Forestry and /or Federal fire control personnel Prot ct one-third of
<br /> Indian River County' s total land ; however, due to limited State and Federal resources , the
<br /> Indian River County Emergency Services Fire Division responds to most wildland fires and is
<br /> supported by the Florida Division of Forestry . Most wildland fires in the Coun y occur during
<br /> Florida ' s dry season , from January through May .
<br /> Historic Events . Statewide , from 1981 through 1996 , an average of
<br /> 6 , 080 wildland fires occurred per year, burning 219 , 725 acres . Because of changing weather
<br /> conditions , the yearly figures range from a low of 3 , 985 wildland fires (with 86 , 944 acres
<br /> burned ) in 1991 to a record high of 14 , 042 wildland fires (with 587 , 400 acresburned ) in 1981 .
<br /> Since 1998 , more than 21 , 000 wildland fires have devastated over 1 . 3 million
<br /> acres and destroyed more than 1 , 000 structures . In 1998 , the previous EI - Niho conditions
<br /> subsided , causing drought conditions and 4 , 890 wildland fires , which burned 506 , 350 acres .
<br /> The drought continued in 1999 , with 5 , 636 wildland fires destroying 355 , 197 acres . In 2000 ,
<br /> another drought stricken year, 6 , 718 wildland fires burned 212 , 415 acres . In 2001 , the
<br /> drought continued , causing 4 , 804 wildland fires , which burned 403 , 740 acres ( Florida
<br /> Division of Forestry , 2004 ) . These fires resulted in numerous fire complexes being
<br /> developed each of those 4 years . This taxed the State 's firefighting resources , those of other
<br /> agencies in the state , and required assistance from other states . The largest contingent of
<br /> air firefighting resources ever collected responded to the wildland fires of 1998 in Florida .
<br /> The Mallory Swamp fire , one of the single largest and most costly wildland fire in Florida
<br /> history , burned 57 , 200 acres near Perry , Florida in May 2001 , costing an esti nated
<br /> $6 . 7 million . Table 4 .20 illustrates the number and total acreage of wildland ires in 2002 by
<br /> ignition type .
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