FIRE HISTORY OF A RED FIR-DOMINATED WATERSHED IN THE NORTHERN SIERRA NEVADA USING FIRE SCARS AND LAKE SEDIMENTS

WATHEN, S.

Ecology Graduate Group, Department of Plant Sciences, One Shields Ave., University of California, Davis, CA 95616

A study was conducted to determine the long-term fire history of the Coburn Lake watershed, presently dominated by red fir (Abies magnifica), located in the upper montane vegetation zone of the northern Sierra Nevada. Slabs were cut from over 180 fire-scarred trees and stumps found within and adjacent to the 30 ha watershed. These samples were analyzed using standard dendrochronological methods to determine the timing and spatial extent of fires over the last 300 years. Fires appear to have been more frequent for the period prior to European American entry into the area than would have been expected based on our limited understanding of red fir fire history. Also, many fires appear to have started around Coburn Lake, suggesting that many fires were set by American Indians prior their extirpation from the area. Interpretation of the charcoal record from Coburn Lake adds further details.