Document


Title

Present and past old-growth forests of the Lake Tahoe Basin, Sierra Nevada, US
Document Type: Journal Article
Author(s): M. Barbour; E. Kelley; P. Maloney; David M. Rizzo; E. Royce; Jo Ann Fites-Kaufman
Publication Year: 2002

Cataloging Information

Keyword(s):
  • Abies concolor
  • Abies concolor
  • Abies magnifica
  • Abies magnifica
  • bark beetle
  • California red fir
  • Calocedrus decurrens
  • coniferous forests
  • cover
  • crowns
  • CWD - coarse woody debris
  • Dendroctonus jeffreyi
  • fire intensity
  • fire management
  • fire suppression
  • forest management
  • forest pathology
  • fuel loading
  • heavy fuels
  • incense cedar
  • insects
  • Jeffrey pine
  • litter
  • montane forests
  • mortality
  • mortality
  • Nevada
  • old growth forests
  • Pinus jeffreyi
  • Pinus jeffreyi
  • plant diseases
  • population density
  • Scolytus ventralis
  • seedlings
  • Sierra Nevada
  • sloping terrain
  • snags
  • stand characteristics
  • stand dynamics
  • succession
  • succession
  • surface fires
  • white fir
  • wildfires
Region(s):
Record Maintained By:
Record Last Modified: December 4, 2019
FRAMES Record Number: 50890
Tall Timbers Record Number: 27612
TTRS Location Status: Not in file
TTRS Call Number: Not in File
TTRS Abstract Status: Fair use, Okay, Reproduced by permission

This bibliographic record was either created or modified by the Tall Timbers Research Station and Land Conservancy and is provided without charge to promote research and education in Fire Ecology. The E.V. Komarek Fire Ecology Database is the intellectual property of the Tall Timbers Research Station and Land Conservancy.

Description

We described 38 relictual old-growth stands -- with data on the mortality, regeneration, floristic richness, fuel load and disease incidence in our study area in the Tahoe Basin of California and Nevada. The stands are within the lower and upper montane zones (1900-2400 m a.s.l.) and they are rare, occupying < 2% of the land in the Basin's watershed. Correlation matrices and ANOVAs of forest types and conifer species with environmental gradients revealed significant relationships with elevation, distance east of the Sierran crest, slope aspect, annual precipitation, date of complete snow melt, litter depth and degree of soil profile development. Pathogens, parasites and wood-boring insects were present on 23% of living trees; 16% of all trees were dead. We compared these stands to a reconstruction of pre-contact Basin forests and to ecologically analogous old-growth forests of Baja California that have never experienced fire suppressionm anagement. Currently, overstorey trees (> 180 yr old) in the Basin stands have ca. 33% cover, 54 m2.ha-1 basal area and 107 individuals.ha-1, values very similar to reconstructions of pre-contact Basin forests and to modern Baja California forests. Understorey trees (60-180 yr old), however, are several times more dense than historic levels and species composition is strongly dominated by A. concolor, regardless of the overstorey composition. The ratio of Pinus: Abies has increased -- and the age structure of extant stands predicts that it will continue to increase -- from approximately 1:1 in pre-contact time to 1:7 within the next century. Disease incidence and mortality in Baja forests were lower. Although we quantitatively defined current Basin old-growth forests -- in terms of stand structure -- we realize that our definition will differ from that of both past and future old-growth forests unless management protocols are changed. © IAVS; Opulus Press Uppsala. Printed in Sweden.

Citation:
Barbour, M., E. Kelley, P. Maloney, D. Rizzo, E. Royce, and J. A. Fites-Kaufman. 2002. Present and past old-growth forests of the Lake Tahoe Basin, Sierra Nevada, US. Journal of Vegetation Science, v. 13, no. 4, p. 461-472.