Fire history was determined for part of the Routt-Medicine Bow National For
est in south-eastern Wyoming using fire-scar and age-class analysis. A comp
osite chronology of fire events was used to determine mean fire intervals (
MFI) for pre-EuroAmerican settlement, EuroAmerican settlement (before 1868
AD), EuroAmerican settlement and modern (after 1912) periods, for all fires
and stand-replacing fires. Point-scale MFI was also determined using grand
means from individual trees. Stand-replacing fires were reconstructed to d
etermine fire rotation. MFI for the entire time period is 5.5-8.4 years. MF
I decreased from 9.3 to 15.7-1.9-2.9 years from the preto post-EuroAmerican
settlement periods, and increased during the modern period. Point-scale MF
Is are longer than MFI of the study area. Fire rotation is 182 years for th
e total period of record, but increased from 127 years during the pre-EuroA
merican settlement period to 170 years during the EuroAmerican settlement p
eriod. Fire rotation during the modern period dramatically increased to 27,
035 years. Results suggest fire suppression may have influenced the fire re
gime. Comparison of regional fire events with fire events from this study i
ndicate regional weather has an important influence on Rocky Mountain fire
regimes.