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EXCERPTS FROM THE SNEP FINAL REPORT TO CONGRESS
 
 
Introduction
 
     The following are key findings quoted from the Sierra Nevada Ecosystem
Project (SNEP), Final Report to Congress, vol. I, Assessment Summaries and
Management Strategies (Davis: University of California, Centers for Water and
Wildland Resources, 1996).  The report summarizes the SNEP completed by the
Science Team.  Volume I encapsules a list of critical findings and a summary
of the assessments, case studies, and alternative management strategies. 
Congress requested this project in the 1993 Interior Appropriations Act.  The
study called for a scientific review of remaining old growth in national forests
in the Sierra Nevada by an independent panel of scientists.  Over 100
additional scientists contributed to this report as well.
 
SNEP Key Findings:  
 
Fire and Fuels
 
   The commonly expected consequence of decades of fire suppression
- that large, infrequent fires are becoming larger and small, frequent
fires smaller - is generally not confirmed by records for 20th century
Sierran forests.  The Plumas National Forest has had no change in the
observed size and frequency of fires during this century (p. 4).
      
   Timber harvest, through its effects on forest structure, local
microclimate, and fuel accumulation, has increased fire severity more
than any other recent human activity.  Logging (including salvage of
dead and dying trees) increases fire hazard by increasing surface dead
fuels and changing the local microclimate, if not accompanied by
adequate reduction of fuels.  Fire intensity and expected fire spread
rates thus increase locally and in areas adjacent to harvest (p. 4).
 
   Although silvicultural treatments can mimic the effects of fire on the
structural patterns of woody vegetation, virtually no data exist on the
ability to mimic ecological functions of natural fire 
(pp. 4-5).
 
   Naturally occurring fire in the Sierra Nevada has influenced Sierran
ecosystems for millennia, influenced biodiversity, plant reproduction,
vegetation development, insect outbreaks and disease cycles, wildlife
habitat relationships, soil functions and nutrient cycling, gene flow,
selection, and ... sustainability (p. 4).
 
 
 
 
Late Successional & Old Growth Forests
 
   The successional old growth forests of middle elevations (west-side
mixed conifer, red fir, white fir, east-side pine types) at present
constitute 7-30% of the forest cover depending on forest type.  On
average, national  forests have about 25% the amount of the national
parks, which is an approximate benchmark for pre-contact forest
conditions.  East-side pine forests have been especially altered (p. 6). 
 
 
   Human activities, particularly timber harvest, indiscriminate burning
in the 19th century, and fire suppression in the 20th century, have
drastically reduced the extent of late successional forests through the
removal of large trees and woody debris and dense ingrowth of shade-
tolerant tree species, leading to greater stand uniformity over large
areas and loss of landscape diversity (p. 6).
 
   Over the past decade, as they have many times in the past, Sierra
Nevada conifer forests have experienced widespread, locally severe
mortality caused principally by bark beetles infesting trees stressed by
drought, over- dense stands, and pathogens. Along the western slopes,
air pollution stress may well have contributed to this extensive
mortality.  Although fire suppression and forestry practices leading to
unhealthy tree densities are implicated in the current die-off, Forest
Service records dating back to the beginning of the century reveal that
periodic insect outbreaks, often associated with droughts, have killed
trees (often just a specific species) over extensive areas of the Sierra
Nevada Tree mortality, even widespread or locally severe mortality, is
an inherent component of Sierran forest ecology and an important
generator of plant and animal habitats (p. 7).
 
   ...existing high-quality late successional forests must be retained and
expanded to support the full range of organisms and functions into the
future, that distribution of late successional conditions across the
landscape involves a combination of focus areas and management of
matrix land and that fire is reintroduced into the forest 
(p. 17).
 
   Excessive sediment yield into streams remains a widespread water-
quality problem in the Sierra Nevada.  The main sources of sediments
are roads of poor design, location, construction, and maintenance and
riparian areas that have been devegetated by logging, fire, mining,
grazing and construction (p. 8).
 
   Anadromous fish (chinook salmon, steelhead), once native to most
major Sierran rivers north of the Kings River, are now nearly extinct
from Sierra rivers.  Dams and impoundments, which block fish access
to streams, together with degraded conditions above dams, have led
to loss of about 90% of the historic habitat in the Sierra (p.8).
 
   Sixty-nine species of terrestrial vertebrates (17% of the Sierra fauna)
are considered at risk by state or federal agencies, which list them as
endangered, threatened, of "special concern," or "sensitive" (p. 5).
 
   The most important identified cause of the decline of Sierran
vertebrates has been loss of habitat, especially foothill riparian habitats
and late successional forests (p. 5).
 
Jobs and the Environment
 
   The number of jobs has more than doubled in the Sierra Nevada
since 1970, but the relative proportion of commodity-producing and
service-producing jobs stayed constant.  Recreation, timber, and
agriculture are the three largest employment sectors directly dependent
on the ecosystem.  In 1990, recreation accounted for 8% of all jobs,
timber 4%, and agriculture 3%.  Diversification has occurred within
each sector (p. 2).
     
   Water is the most valuable commodity, followed by timber, livestock
and other agricultural products, based on gross revenues. The Sierra
Nevada ecosystem produces about $2.2 billion worth of commodities
and services annually, based on estimates of direct resource values (not
the total revenue produced by resource-dependent activities.)  Water
accounts for more than 60% of that total value, followed by other
commodities totaling 20%, and services also totaling 20% 
(p. 3).
 
   Communities in the Sierra Nevada are dependent on the ecosystem
for a combination of direct and indirect natural resource benefits,
including noneconomic benefits associated with aesthetic and sense-of-
place values.  Few economies are dependent exclusively on resource-
extractive activities (timber, mining, grazing) (p. 3).
 
   Timber industry employment may decline from present levels due
to trends of increasing labor productivity within the region and a shift
in remanufacturing facilities out of the region. Timber harvests from
federal land will have only a modest impact on trends in local
employment. Woods work (fuels management, environmental
restoration, etc.) in the Sierra Nevada can make only a modest
contribution to alleviating the effect of the decline on local workers 
(p. 3).
 
 
 
To obtain a copy of the summary of the Sierra Nevada Ecosystem Project: Final
Report to Congress, please contact: Sierra Nevada Ecosystem Project, 916/752-
8070, Room 2140, Hart Hall, University of California, Davis, CA 95616 or
check http://www.ceres.ca.gov/snep