Comparison of Two Approaches for Determining Fire Dates from Tree Scars

Knowledge regarding the historic role of fire in forest ecosystems is often derived by dating fire scars. Fire history studies in boreal and western coniferous forests have used either complete or partial cross sections cut from fire-scarred trees. The occurrence of missing or false rings presents an obstacle to the accurate dating of individual fires. Two different techniques of dating partial cross sections of fire-scarred ponderosa pine (Pinus ponderosa Laws) were compared using the same samples. Method I involves the tabulation of raw dates followed by a subsequent adjustment based on synchronization with fire dates from adjacent trees. Method II uses correlations with master chronologies based on analysis of increment cores taken in the same region as the sampled fire scar sections..