Stephens fire data from Sagehen Experimental Forest - IMPD USSEF001 Stephens, S.L. Stephens, S.L. earth science/paleoclimate/fire history|tree ring (age,null,null,year Common Era,null,fire history|tree ring,null,null,N,null) earth science/paleoclimate/fire history|tree ring (sample identification,null,null,dimensionless,null,fire history|tree ring,null,null,N,null) earth science/paleoclimate/fire history|tree ring (tree demographic and injury and fire event code,wood,null,dimensionless,null,fire history|tree ring,null,null,C,text description of fire event; refer to IMPD documentation for description of codes) earth science/paleoclimate/fire history (Sagehen Experimental Forest - IMPD USSEF001>LATITUDE 39.441552>LONGITUDE -120.232072) For thousands of years, fire has shaped coniferous forests of the western United States. In more recent time, land use practices have altered the role fire plays in the Sierra Nevada. By understanding the past, land managers can design better fuel treatments today. This research explores the fire regimes of Sagehen Experimental Forest in the eastern Sierra Nevada, California, through a fire scar reconstruction of lower elevation Jeffrey pine (Pinus jeffreyi Balf.) and Jeffrey pine-mixed conifer stands. Prehistoric and historic land use practices, fuel accumulation, and climate influenced the fire regime over three periods of time: pre-settlement (1700 to 1859), settlement (1860 to 1925), and suppression (1925 to 2006). Over the period of analysis, 293 fire scars were assigned calendar years. The mean composite fire return interval for all samples in the study area was two years. The mean composite fire return interval was significantly longer for the suppression period than both the pre-settlement and settlement periods. The lack of sufficient fire intervals for analysis using a filter that included fires that scarred at least three or more trees and 25% of the total sample indicates that fires in the study area are small in spatial extent. The proportion of dormant season fires increased from pre-settlement through the suppression period. No fires were recorded as middle and early earlywood during the suppression period. A superposed epoch analysis found significant correlation to warmer (Pacific Decadal Oscillation) and wetter (Palmer Drought Severity Index) conditions three years prior to large fire events during the pre-settlement period. During the post-settlement era, large fire years were correlated to El Niño conditions for two consecutive years prior. Little synchrony of fire events was recorded between fire scarred tree clusters. These findings suggest that small frequent prescribed burns would best mimic the pre-settlement fire regime if fire is reintroduced into the ecosystem. STUDY NOTES: This dataset was contributed as part of the North American Tree-ring Fire Scar Synthesis (NAFSS) project (https://www.ncei.noaa.gov/access/paleo-search/study/34853). Data were contributed to the project from the original data generators. Sample Storage Location: Dating Method: Dated Related ITRDB_Chronology: Not Applicable Fire scar data from this site are available in FHX2 format at: https://www.ncei.noaa.gov/pub/data/paleo/firehistory/firescar/northamerica/ussef001.fhx along with associated metadata at: https://www.ncei.noaa.gov/pub/data/paleo/firehistory/firescar/northamerica/ussef001-fhx-noaa.txt NCEI-Paleoclimatology https://www.ncei.noaa.gov/products/paleoclimatology - NOAA World Data Service for Paleoclimatology Investigator : Stephens, S.L. 2026-07-09 ONLINE Files online, ASCII https://www.ncei.noaa.gov/access/paleo-search/study/44994 https://www.ncei.noaa.gov/pub/data/paleo/firehistory/firescar/northamerica/ussef001.fhx https://www.ncei.noaa.gov/pub/data/paleo/firehistory/firescar/northamerica/ussef001-fhx-noaa.txt https://www.ncei.noaa.gov/pub/data/paleo/firehistory/firescar/northamerica/ussef001.fhx https://www.ncei.noaa.gov/pub/data/paleo/firehistory/firescar/northamerica/ussef001-fhx-noaa.txt English https://www.ncei.noaa.gov/access/paleo-search/study/44994 https://www.ncei.noaa.gov/pub/data/paleo/firehistory/firescar/northamerica/ussef001.fhx https://www.ncei.noaa.gov/pub/data/paleo/firehistory/firescar/northamerica/ussef001-fhx-noaa.txt Vaillant, Nicole M.; Stephens, Scott L.2009Fire history of a lower elevation Jeffrey pine-mixed conifer forest in the eastern Sierra Nevada, California, USAFire Ecology534394010.4996/fireecology.0503004 START YEAR: 1575 CE * END YEAR: 2006 CE -120.232072 39.441552 -120.232072 39.441552