Extreme Fire Behavior
Seventy-three clearcuts in western larch/Douglas-fir forests of western Montana were broadcast burned over a wide range of environmental conditions for the purpose of quantifying fire characteristics and burn accomplishment. The moisture content of the upper duff, and the National Fire-Danger Rating System Buildup Index (1964) were found to be important predictors of both the heat pulse to the site and the amount of duff removed by the fire. The same two variables along with the preburn weight of 1 to 10 cm fuels were the best predictors of the amount of fuel consumed by the fire. Associated studies are yielding information on tree regeneration, vegetal development, small mammal population dynamics, nutrient cycling, water quality, runoff and soil erosion, smoke dispersal, and convection column height-all related to varying fire characteristics and burn accomplishment.