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TRAPPER lSINB PRESCRISSD BURN FIRE BEHAVIOR NARRATIVE All calculations are based on the BEHAVE program. SAGE BRUSH - Calculations indicate adequate burning should be achieved with 1 HR fuels between 6-12 moisture content. A minimum of 6 mph and a maximum of 10 mph mid-flame wind speed (MEWS) would be necessary to adequately accomplish goals of top kill in the brush. ROS with 1 HR F.M. of 6 and MEWS of 10 is estimated at lOch/hr. Calculations show that as the temperature increases from 70 to 90•degrees, the Probability of Ignition (PI) increases from 308 to 608. PI predicts the probility that a fire brand will ignite if it lands on fine fuels. Should a spot fire occur in the non-target fuels, calculation show resources on the burn will be able to contain the spot in 30 minutes or less. Spot fires in the target fuels may also occur. The Burn Boss will make the decision at that time to allow such fires to burn or to suppress their spread. OAR BRUSH MIXTIIRE - Calculations show adequate burning should be accomplished with the 1 HR fuels between 6-12 moisture content. MEWS should be between 4-8 mph. ROS is very dependent on 1 HR FM levels in response to MFS~'S. The lower FM requires lower MEWS to remain below the 40ch/hr maximum ROS. Desired parameters for ROS, FL, and intensity are indicated on the output tables from BEHAVE, and are attached to the burn plan. These tables will be on site during the burn and will be monitored closely by the Prescribed Fire Monitor assigned to the burn. The probability of a spot fire increases with temperature. The PI is the same as for the sage brush, as the fine fuels are similar. Because of potential spotting, the continuous non-target fuels, and difficulty to construct afire break through oak brush, one dozer (min. DB) must be on site during the burn. Also, a second dozer must be readily available should the need occur.