Wednesday, 19 November 2003: 5:00 PM
Fire behavior and fire seasonality in the Washington Cascades
This study examines the influences of fire seasonality on fire behavior and resulting landscape patterns in the dry forests of the Washington’s eastern Cascades. We used a multi-method approach, including analysis of district fire records, computer modeling, and spatial pattern analysis. Fire records were first used to compare the spatial patterns resulting from summer wildfires to management ignited prescribed fires burning under spring and fall conditions. This historical information was then used to calibrate several computerized fire modeling routines. Potential fire effects and fire behavior were simulated in several watersheds using meteorological records and FlamMap and FARSITE software. Fragstats software was then used to compare the spatial patterns predicted by FARSITE for fires burning in different seasons. Results indicated significant differences in fire behavior and fire effects during the spring, summer, and fall seasons. Additionally, spatial pattern analysis indicated significant seasonal differences in several landscape metrics including fire size, fire perimeter, and mean patch size of areas experiencing canopy removal. The results suggest that fire behavior modeling can provide fire managers a tool for planning fire use programs as well as predicting seasonal variation in fire behavior at a landscape level.