Skip to main content
U.S. flag

An official website of the United States government

Holocene fire and vegetation dynamics in a montane forest, North Cascade Range, Washington, USA


Susan J. Prichard
Ze'ev Gedalof
W. Wyatt Oswald



Publication type:

Scientific Journal (JRNL)

Primary Station(s):

Pacific Northwest Research Station


Quaternary Research

DOI: 10.1016/j.yqres.2009.03.008


We reconstructed a 10,500-yr fire and vegetation history of a montane site in the North Cascade Range, Washington State based on lake sediment charcoal, macrofossil, and pollen records. High-resolution sampling and abundant macrofossils made it possible to analyze relationships between fire and vegetation. During the early Holocene (> 10,500 to ca. 8000 cal yr BP) forests were subalpine woodlands dominated by Pinus contorta. Around 8000 cal yr BP, P.contorta sharply declined in the macrofossil record. Shade tolerant, mesic species first appeared ca. 4500 cal yr BP. Cupressus nootkatensis appeared most recently at 2000 cal yr BP. Fire frequency varies throughout the record, with significantly shorter mean fire return intervals in the early Holocene than the mid and late Holocene. Charcoal peaks are significantly correlated with an initial increase in macrofossil accumulation rates followed by a decrease, likely corresponding to tree mortality following fire. Climate appears to be a key driver in vegetation and fire regimes over millennial time scales. Fire and other disturbances altered forest vegetation at shorter time scales, and vegetation may have mediated local fire regimes. For example, dominance of P. contorta in the early Holocene forests may have been reinforced by its susceptibility to frequent, stand-replacing fire events.


Prichard, Susan J.; Gedalof, Ze'ev; Oswald, W. Wyatt; Peterson, David L. 2009. Holocene fire and vegetation dynamics in a montane forest, North Cascade Range, Washington, USA. Quaternary Research. 72:57-67.

Publication Notes

  • We recommend that you also print this page and attach it to the printout of the article, to retain the full citation information.
  • This article was written and prepared by U.S. Government employees on official time, and is therefore in the public domain.