Download A. The spring drought # wildfires/year # acres

PRESCRIBED FIRE BASICS
PAT DEREN, FLORIDA FOREST SERVICE
Fire in Florida:
Historical Perspective
 Lightning-caused fires
 mainly summer months
 most area probably burned in May-June
 Human-ignited fires
 native Americans used for variety of reasons
 widely applied in early 1900s - mainly winter
 fire exclusion policy in last 70 years
# wildfires/year
# acres burned/year
Q. Why this peak?
A. The spring drought
Florida Ecosystems
Fire Maintained
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Flatwoods
High pine / Sandhill
Scrub
Sawgrass prairies
Cypress swamps
Other grasslands
Freshwater marshes
Salt marshes
Fire Influenced
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Upland hardwoods
Dunes
Subtropical forests
Mangroves
Grassland or wet prairie
Fire interval 1-6 years
If Fire is Absent?
Vegetation
 tree density & cover increase
 composition shifts to shade tolerant
species
 growth rates & tree vigor decline
 herbaceous forage and shrubs decline
Soils
• organic matter accumulates
• nutrient cycles slow
If Fire is Absent?
 Animals
 late successional species replace seral
species
 populations of many species decline
 endemic “pest” insects & diseases increase
 Ecosystem processes
 tend to simplify in structure & function
 stream flow & on-site water balance
decrease
 potential for large fires increase
Fire Effects on Plant Communities
Competition for moisture, nutrients & light are
temporarily reduced
Certain species may be selectively eliminated
Species composition and successional stages are altered
Susceptibility to blowdown may be altered
Effects on Animals:
General Principles
Many Florida species have evolved in a
fire environment
Mortality levels are generally low
Effects on cover and food sources are
substantial but vary across the
landscape
Fire intensities may be:
 reduced by grazing
 increased by insect damage
Firing Techniques
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Backing fire
Head fire
Flanking fire
Spot fire
Ring fire
Always do a test fire!
All techniques begin with a
secure baseline
BOATING
SMOKE MANAGEMENT DEFINED
• A plan of action where prescribed burning is
conducted in such a way that smoke produced
is dispersed without causing a health or safety
hazard.
What is Smoke??
• Byproduct of the combustion process
– Major Products of Combustion:
• Water Vapor
• Carbon Dioxide (CO2)
– Major Pollutants of Combustion:
• Carbon Monoxide (CO)
• Particulate matter**
SMOKE SCREENING PROCESS
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Determine Fuels
Plot the Smoke Plume
Identify SSA’s
Identify Critical SSA’s
Minimize Risks