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fire resistant trees can not withstand the intensity of these fires. In 

 forests where fuels have built up, wildfires burn through the crowns 

 of the forest consuming everything except trunks and larger 

 branches. Within the perimeter of the fire, few areas are lightly 

 burned. Some trees may survive in the lightly burned areas, but 

 most trees perish due to the pervasive intense heat. 



Following these wildfires, multi-age forests may either convert to 

 even-age forests, leave single trees where the forest once stood, or 

 convert to a non forest type. If re-burned before the post burn 

 regeneration produces seed, the forest is replaced by brush. Most 

 likely, the brush will last for a long time, and from a practical 

 management perspective the resulting non forest community is 

 permanent, or at least semi-permanent. 



In addition to increased fire intensity and severity, the uniformity 

 and size of wildfires increase. Such fires are more uniform because 

 combustion is more complete. The subsequent landscape mosaic is 

 less diverse. Complex spatial and temporal mosaics of historical fires 

 are lost in a single fire. Tens of thousands of acres burn in a single 

 fire where hundreds of acres would have normally burned. 



The loss in diversity on the landscape and structural diversity within 

 the fire perimeter causes decline in biodiversity and affects wildlife 

 habitats over large areas. Large intense fires consume organic matter 

 on the forest floor leaving the watershed exposed to erosion. Streams 

 may clog with sediments affecting fish habitat. In addition, wildfires 

 are dangerous to forest residents and to fire fighters. They are 

 expensive to suppress and to rehabilitate. The loss of private 

 property drives the costs up even higher. A single fire may burn for 

 a month or longer and cost more than a million dollars a day to 

 suppress. Rehabilitation and property loss may run into the millions. 



2. What are the primary ecosystems that have been most affected by 

 the exclusion of fire? 



