United States Department of Agriculture, Forest Service
Pacific Southwest Research Station
Sierra Nevada Research Center
The Teakettle Experiment: Fire and Thinning Effects on Mixed-Conifer
Ecosystems.
The Research:
After a century of fire suppression, thinning and prescribed fire
are widely used to restore Sierran forests. Managers, however,
have little information about the comparative effects of these
treatments on ecosystem response or forest health. Does mechanical timber harvesting mimic the ecological effects of the
natural fire disturbance regime, and if it does not, what ecosystem
functions and processes are being altered and what are the consequences of these changes? Using 18 replicated four ha plots, two
levels of burning (no burn and prescribed fire) and three levels
of thinning (no thin, understory thinning, overstory thinning)
were applied in a full-factorial design. Pre-treatment data was collected for 2-3 years, fire and thinning treatments were completed
in 2001, and for 3 years post-treatment ecosystem response was
assessed with 17 concurrent studies. To facilitate interdisciplinary analysis between the studies, all data were collected at common sample points, a grid of 402 mapped, marked locations. In
addition all trees, snags, logs and shrubs were tagged, tallied, and
mapped before and after the experiment on the 72 ha of sample
plots.
Objectives:
• To assess how widely used restoration methods, prescribed
fire and thinning, affect ecosystem structure, composition
and function.
• To compare treatments effects against a reconstruction of
forest stand conditions in 1865 under an active fire regime.
• To understand disturbance and successional dynamics in
Sierra forests.
• To assess how energy, nutrient, water flows and trophic
structure are affected by treatments.
To evaluate mixed-conifer ‘health’ following 6 restoration
treatments.
USDA Forest Service
Pacific Southwest Research Station
Sierra Nevada Research Center
Photo: Malcolm North
Our Mission:
Sierra Nevada Ecosystems are
complex and our knowledge
of them is incomplete. As
a result, the long term outcome of any given land and
resource management strategy
is uncertain. We will provide
assistance to land managers
and policy makers by addressing this management dilemma
through targeted research,
emphasizing an integrated,
ecoregional approach to examine particular physical, ecological, and socio-economic issues,
across a range of appropriate
spatial and temporal scales
specific to each issue.
This unit will represent the
collective research expertise
and interests of scientists
located in Fresno, Davis and
Albany as well as other scientists within the Pacific Southwest Research Station. With
a full spectrum of research,
from long term, fundamental
research to short-term, tactical applications, this Center
is intended to support conservation, restoration, and
sustainable utilization of the
lands within the Sierra Nevada
ecoregion.
Application of Research Results:
Results have direct relevance to forest management in the Sierra Nevada following
a century of fire suppression. Forest health has been set as a goal for restoration
treatments. Although the term may be vague, a better understanding of ecosystem
structure, composition and functional response to restoration treatments would
certainly help assess forest response. Beside the publications listed below, a film and
interactive DVD is being produced to communicate results with forest managers,
students and the public.
Location:
Old growth mixed-conifer forests of the Teakettle Experimental Forest, 80 km east
of Fresno at 2200 m elevation.
Future Directions:
Using the information from this
research, a second experiment is
planned at the watershed scale
(400 ha) which will compare the
effects of new fire and thinning
prescriptions on mixed-conifer
restoration. This phase will vary
thinning prescriptions by size
using flexible diameter guidelines,
and will apply prescribed fire during the historical (late summer)
season.
Photo: Brian Oakley, University of Washington
USDA Forest Service
Pacific Southwest Research Station
Sierra Nevada Research Center
For further inforamation contact:
Malcolm North, Research Ecologist
530-754-7398
Peter Stine, Program Manager
Jim Sedell, Station Director
Pacific Southwest Research Station
Photo: Malcolm North
www.fs.fed.us/psw/programs/snrc
Albany Location
800 Buchanan Street
Albany, CA 94710
Mailing Address:
P.O. Box 245
Berkeley, CA 94701
Phone: 510-559-6300
Fax: 510-559-6440
Davis Location:
2121 Second Street
Suite A101
Davis, CA 95616
Phone: 530-759-1700
Fax: 530-747-0241
Fresno Location:
2081 E. Sierra Avenue
Fresno, CA 93710
Phone: 559-323-3200
Fax: 559-297-3355