Joint Fire Science / Red Mountain Mastication Study
» Fire Behavior Data Collection
Key characteristics of fire behavior will be measured and paired with information on fuel characteristics in order to develop and calibrate a custom fuel model for each treatment. Direct fire behavior measurements will be summarized for use by managers in predicting fire behavior during prescribed burns of masticated units. The data will also be analyzed in relation to tree mortality.
Four key fire behavior characteristics will be measured at each plot burned including, rate of spread, flame length, soil surface temperature, and fire type. In addition, weather data will be collected (temperature, humidity, and windspeed) before and during the prescribed burn. We will place sensors and make observations at least at each of the four subplots within each treatment plot.
Rate of spread: Rate of spread will be quantified in two ways. First, we will observe and video fire spread. Second, rate of spread sensors will be placed in each plot. These sensors contain a date and time clock along with a thermocouple which measures temperature. Locations and the time measurements of the five sensors will provide for calculation of rate of spread. Triangulation will be used to determine the direction and forward rate of spread, regardless of the direction of fire spread and variability of rate of spread (Simard et al. 1984).
Flame Length and Fireline Intensity: A minimum of four color video cameras (3ccd), housed in fire-resistant cases (Kautz 1997) that will be used for each 5 acre burn plot to record images from which flame height, flamelength, and fire duration can be measured. These will be placed in locations that include a view of one to several subplots and autonomous sensors. In addition, passive flame height sensors described in Finney and Martin (1992) will be established on site. These sensors are composed of strings dipped in flame retardant and are then nailed up on metal stakes that are set up in the burn area. Twelve passive flame height sensors will be placed in each 5 acre burn plot, four associated with each of the randomly placed fuel subplots.
Soil Surface Temperature and Duration: Surface and soil temperatures will be measured in order to determine the role of heat (maximum and duration) plays in tree mortality compared to crown scorch. Thermologgers will be used in each of the burn plots. Each thermologger is composed of Type K thermocouples connected to dataloggers. On each thermologger, four thermocouples will be attached, with two placed at surface litter, and two within the top 6 cm of the soil surface.