Background.
 
This report was prepared for and funded by a California non-profit which wishes to remain anonymous on our website.  Recognizing the importance and timeliness of this information, that group has authorized its release or consideration by the various groups who may find it useful. The report consists of the enclosed report, attached tables, and a number of watershed maps, showing land ownership, use, urbanization, fire probability, and impacts of mapped roads on mapped riparian systems in the 26 major Sierra watershed.   The information herein is solely the responsibility and the work of its authors and does not reflect an agreement with the opinion, policy, or position of any organization.

Tables and maps not found can be supplied on request.
 
 
 

ABSTRACT
 
ISSUES SUMMARY

Summary Report with Maps in PDF format

PART I.   FOREST RESTORATION NEEDS ASSESSMENT

    1. Introduction and Objectives
    2. Assessing Forest Restoration Needs in the Sierra Nevada
        The Spatial Analysis
            River Basins and Subregions
        Experimental Design
            Land Protection Status
            Urbanization & Human Settlement
          Road Impacted Waterways
          Fire Return Intervals
             Forests
          Restoration Goals

    3. Forest Restoration Needs
        Land Protection Status
        Vegetation
        Impacts of Urbanization, Roads, Fire Suppression  
        Forest Restoration needs

PART II.   ECONOMIC EFFECTS OF FOREST RESTORATION
 
    4. The Sierra Nevada Economy
        Overview of population, income, poverty, employment
        Resource vs. amenity-based ecomonies
 
    5. The Economic Enterprise of Forest Restoration
        Costs, Accumulating Benefits and Types of Activities

    6. Financing Forest Restoration
        Existing and New Sources of Funding
        Market Based Approaches

Tables

Table 2-1: Twenty-Six Primary River Basins of the Sierra Nevada>

Table 2-1: Twenty-Six Primary River Basins of the Sierra Nevada

Table 2-2: GIS Data Analysis Procedure

Table 2-3: Vegetation Classifications for Data Analysis and Map Displays (Holland, 1986)

Table 2-4: Residential Density Classifications

Table 3-1: Land Ownership in the Sierra Nevada

Table 3-2: Acres of Forests in Sierra Nevada River Basins

Table 3-3: Settled Forestland

Table 3-4: Percentage Cover on Two Land-use Types Associated with Human Settlement

Table 3-5: Decreases in Canopy Cover at Varying Lot Densities

Table 3-6: Forest Roads in Riparian Zones in Selected Hydrologic Sub-Areas

Table 3-7: Forest Roads in Riparian Areas by Land Protection Status

Table 3-8: Acres by Fire Return Interval less than 250 years

Table 3-9: Acres by Fire Return and Land Protection Status

Table 3-10: Acres by Fire Return and Dominant Forest Type

Table 3-11: Summary of Forest Restoration Needs in Sierra Nevada

Table 4-1: Projected Population Growth for Sierra Nevada Counties

Table 4-2: Poverty Rates in Sierra Nevada Timber Counties

Table 4-3: Small Business in the Sierra Nevada

Table 4-4: Travel and Tourism-related Employment in the Sierra Nevada

Table 4-5: Annual Ecosystem Use Values for the Sierra Nevada

Table 4-6: Annual Hydroelectric Production and Value for Sierra Nevada River Basins

Table 5-1: Estimated Costs of Fuels Treatments

Table 5-2: Estimated Costs of Roads Treatments

Table 5-3: Estimated Costs of Immediate Fuel Management Needs

Table 5-4: Estimated Costs of Addressing Impacts from Roads in Riparian Areas

Table 5-5: Wages for Selected Occupations in Natural Resources Management

Table 5-6: Average Socioeconomic and Community Capacity Scores by Region

Figures

Maps

PART I. FOREST RESTORATION NEEDS ASSESSMENT
 
 

1. INTRODUCTION AND OBJECTIVES
 

The principal goal of this study is to explore the economic implications of pursuing restoration of Sierra Nevada forests. A spatial analysis that identifies and quantifies areas likely to be candidates for restoration is required for the economic assessment to be founded on factual information about forest conditions throughout this highly varied landscape.
 

We have identified three primary stressors on forest ecosystems which have impacted Sierra Nevada forests to the point where restoration is needed. These stressors include: road-building in forest riparian environments, suppression of natural fire regimes, and human settlement. Fire suppression and roading in forests are significant stressors associated with timber harvesting, as is the removal of trees. The effects of tree removal on the structure and composition of forests are not directly addressed here because accurate and timely information is not available for the whole region. Information on the current management of forest lands is included however, and is used to infer where harvesting has occurred.
 

Forest restoration is the focus of this study and should be distinguished from the broader term Òwatershed restoration.Ó A broad range of impacts and needs affects entire watersheds in the Sierra Nevada. Watershed restoration emphasizes the linkage between upstream and downstream conditions in aquatic environments and must examine many issues not addressed by this more focused analysis of forest restoration.
 

The spatial analysis conducted for this study required the assembly of a Geographic Information System (GIS) constructed from digital files obtained through the Sierra Nevada Ecosystem Project (SNEP) and other sources. This information supports the first spatially-explicit estimates of regional forest restoration needs ever reported and will significantly advance conservation management, planning and research efforts underway throughout the region.
 

Using the spatial data, we examined the costs of forest restoration, potential sources of funding for restoration, and the potential for restoration to stimulate local economies. These issues are addressed in the context of key Sierra Nevada economic indicators. The indicators reveal a region in transition toward greater economic diversification. The quality of life in the region supports the trend toward diversity by attracting the social capital that supports enterprise. Forest restoration will be essential to preserving the quality of life in the region.
 

2. ASSESSING FOREST RESTORATION NEEDS
 

When we examine large landscapes with an eye toward solving environmental problems, the watershed presents itself as a uniquely valuable unit on which to base a wide array of analyses. The simple reason being that the impacts of human activity on the land flow downhill and inevitably become apparent in the quality of aquatic and riverine environments. The integrity of forest ecosystems is without question a fundamental determinant of watershed health, since forests buffer the effects of natural and human-caused disturbances, regulate water flow, and protect water quality. Large watershedsÑthe river basins of the Sierra NevadaÑare used here to report forest restoration needs in the Sierra Nevada.
 

Human culture has delineated boundaries across the landscape which reflect the values of early inhabitants and the social and political structure of contemporary society. Similarly, other terrestrial mammals have ranges and habitat often irrespective of watershed boundaries. From the ecological perspective the watershed is a compelling way to approach environmental understanding and protection. But it is critical that we recognize human communities as artifacts of ecology as well, and that we are careful not to ignore community boundaries based on a perceived ecological imperative. In promoting a river basin perspective on Sierran forest restoration, this report recognizes the link between forest protection and water quality and aquatic ecosystem health.
 

This section of the report describes the approach we took to develop a spatially explicit assessment of forest restoration needs in the Sierra Nevada. The experimental design shows what specific questions we asked, what data we used, and how we manipulated them. The goals of forest restoration as they relate to a regional analysis such as this are also discussed.
 

2.1 Discussion of Spatial Analysis
 

The spatial analysis phase of this project was designed to objectively identify forests in need of restoration and offer an alternative to the anecdotal, popular, and disparate views on regional forest restoration priorities. There is a recognized need to expand the information sources used for conservation management, planning, and research beyond site-level characteristics to provide a consistent means for placing localized information into regional and range-wide contexts (Jennings, 1997). This analysis yields findings which complement, rather than substitute for, local assessments for forest restoration.
 

A spatially explicit and partially complete environmental information system for the entire Sierra Nevada was assembled for the Sierra Nevada Ecosystem Project (SNEP). Our analysis benefited from the SNEP effort and observed the boundaries established by that project for the Sierra Nevada Ecoregion (SNEP, 1996).
 

We constructed a Geographic Information System (GIS) from digital files obtained through the Sierra Nevada Ecosystem Project (SNEP) and other sources. A river basin template was selected for organizing the GIS and reporting findings. Subregions were further defined to group river basin findings. These subregions reflect both the natural and social character of different parts of the Sierra Nevada.
 

The principal management activities which impact forest ecosystems, include timber harvesting, fire suppression, road construction, and residential development. Our purpose was to identify the location and character of forests altered by these activities. The experimental design for characterizing these forests is based on the availability of range-wide data produced by SNEP scientists and other researchers. For example, forest areas in need of restoration from grazing impacts are not identified in this study, since no system-wide assessment of forest grazing effects has been performed. This analysis does not seek to identify areas to be targeted for protection, as does GAP analysis, but rather to describe forests that can be enhanced or preserved through active restoration.
 

Map: River Basins of the Sierra Nevada
 

2.1.1 River Basins and Hydrologic Subareas
 

The river basins we selected for analysis were derived from Hydrologic Areas and Hydrologic Sub-Areas in the CalWater classification system currently in use by public resource agencies (Map 1). CalWater is a set of standardized watershed boundaries, nested into larger previously standardized watersheds, meeting standardized delineation criteria (Brandow, 1994). Along the western side of the Pacific Crest, the river basins of the Sierra Nevada form the headwaters of the Sacramento-San Joaquin River Delta. South of the San Joaquin Basin, Sierran rivers feed the Tulare Lake Hydrologic Region which is an enclosed basin. The North and South Lahontan Hydrologic Regions drain the east side of the Sierra Nevada into extensive internally drained valleys in California and Nevada.
 

Only portions of the basins within the Sierra Nevada Ecoregion (SNEP, 1996) and within California are considered in this report. Several basins on the east side, including the Tahoe Basin are truncated by the State line. Hydrologic Sub Areas (HSAs), identified on maps with a five-digit number, are subwatersheds within each river basin, and are used to more precisely characterize restoration needs within a river basin.
 

The twenty six primary river basins of the Sierra Nevada, broken into five subregions in this report, range in size from 274,344 to 1,751,590 acres (Table 2-1). Eighteen Sierra counties intersect these river basins as illustrated in Map 2.
 

2.1.2 Subregions
 

Subregions were delineated based in part on the diverse natural character of the Sierra Nevada as well as on cultural features which give even greater distinction to more and less populated areas.
 

North

The North includes five river basins belonging to the Feather (North Fork, East Branch North Fork, Middle Fork), Sacramento (Mill, Big Chico, and Butte Creeks), and Susan (Honey and Eagle Lakes) Rivers. Lassen, Plumas and portions of Tehama and Butte Counties are located in this heavily forested region of the Sierra Nevada.
 

North Central

The North Central subregion includes the Yuba, Bear, American, and Consumnes River Basins west of the Pacific Crest, and the Truckee River and Lake Tahoe Basins on the east side. The Bear and North Fork American Rivers are combined in this analysis. Sierra, Nevada, Placer, El Dorado Counties, and a portion of Yuba County comprise the political landscape of the North Central Region. Heavily populated (more than 70% of all Sierra Residents) and possessing world renown rivers and lakes, this subregion experiences the greatest forest stress.
 

Map 2: Counties and River Basins of the Sierra Nevada
 
 
 
 

Table 2-1: Twenty-Six Primary River Basins of the Sierra Nevada
 

Table 2-2: GIS Data Analysis Procedure
 

data Function	digital Coverage	Treatment of data	MAPS	TABLES
Select forest areas At-Risk to management with Sierra Nevada	1. Land Mgmt/Ownership (Davis, Stoms, 1996);  2. GAP Vegetation (Holland, 1986)  3. Calveg (Parker, Mathias, 1977)  4. SNEP Boundary   5. CalWater Version 2 (CDF)  6. USGS 7.5 min. Topo Index (USGS, 1993)	7. Maintain original 5 Land Mgmt/Ownership classes  8. Aggregate forest veg into forest types for map (further aggregated into 6 classes for data analysis)  9. Remove all large bodies of water using CALVEG water layer.   10. Make consistent with SNEP boundary  11. Select, modify, superimpose Hydrologic Sub Area (HSA) and River Basin boundaries  12. Overlay USGS 7.5 minute topo index	River Basins; Land Protection Status;  Forest Vegetation	Acres in each river basin;  Acres in Land Protection Classes;  Acres in Forests by basin

 

HUMAN SETTLEMENT

 

Evaluate forests affected by human settlement

1. Residential Density, 1990 (Duane, 1996)  2. Forest Type

1. Reclassify by original 11 density classes (0 to >640- units/sq. mi)  2. Select polygons for higher densities (20 to >640 units/sq. mi.)  3. Intersect with forest types   4. Assign coefficients for density, based on forest type (McBride, et al, 1996)

Residential Density, 1990 (acres/dwelling unit)

Acres of forest type affected by human settlement  (canopy loss)

 

ROAD-IMPACTED WATERWAYS

 

Identify riparian areas potentially affected by roads

1. Streams (USGS, 1993)  2. Rivers (USGS, 1993)  3. Lakes (USFS, 1:24K)  4. Roads (USGS, 1993)  5. CalWater Version 2 (CDF)  6. Forest Type (Holland, 1986)  7. Land Protection Status (Davis, Stoms, 1996)

8. Fix waterways buffer at 46 m (150 ft)  9. Overlay roads onto buffered waterways  10. Calculate road and lengths where adjacency occurs  11. Overlay HSAs   12. Overlay land protection status  13. Overlay Forest Type

Roads within 150 feet of Waterways

Miles of Road in Riparian Areas; Land Protection Status of Miles of Road affecting Riparian Areas; Forest type and Road effects.

 

FIRE SUPPRESSION

 

Identify candidate areas for high priority fuel management

1. Fire Return Intervals (Sapsis, et al, 1996)  2. Forest Type (Holland)  3. Land Protection Status (Davis, Stoms, 1996)  4. CalWater Version 2 (CDF)

5. Overlay with Land Protection Status  6. Overlay with Forest Vegetation  7. Conduct analysis only for FRI 1-100 and 100-250 years in Basins and HSAs

Fire Return Interval

Acres in FRI 1-100 and 100-250; FRI acres in dominant forest types; FRI acres by Land Protection Status

 

FOREST ASSETS

 

Identify where assets occur relative to restoration needs

1. LS/OG (Franklin, Fites-Kaufmann, 1996)  2. Ecologically Significant Areas (Millar, et al, 1996)  3. Sequoia groves (SNEP; USFS)  4. CalWater Version 2 (CDF)

Giant Sequoia Groves;  LS/OG ;  Significant Natural Areas

 

2.2.1 Land Protection Status and Vegetation Base Coverages
 

Land Management And Ownership

Land management and ownership for the Sierra Nevada were described in SNEP based on work completed by Frank Davis and David Stoms in a collaboration between SNEP and the National Biological Service Gap Analysis Project (NBS GAP). Their classification is available for 73 percent of the SNEP core area. The databases used in the SNEP/NBS GAP analysis comprise the most spatially detailed land management maps ever assembled for the region as a whole (Davis, Frank W., Stoms, David M., 1996). These data were not modified for this report. Areas described in this report which are not covered by the Davis and Stoms analysis were assigned classifications based on land ownership which provides a more coarse description of management activity. Those areas with less detailed management information include the Mill/Big Chico/Butte Creeks Basin, a portion of the North Fork Feather River Basin, the Honey-Eagle Lakes Basin, and almost the entire East side below the Carson River Basin.
 

Vegetation in the Sierra Nevada Ecoregion

Vegetation types for the Sierra Nevada Ecoregion are derived from Holland (1986) which classifies vegetation based on overstory described by one to three species, each contributing more than 20% of the relative canopy. These species are classified into natural plant community types used by the California Department of Fish and Game, Natural Heritage Division. We aggregated Holland forest vegetation to simplify map displays and data analysis. We used greater detail (less aggregation) for the maps than for data analysis (Table 2-3). Vegetation maps are not included in this report because of budget limitations.
 

Vegetation for areas outside of the Sierra Nevada Ecoregion was derived from Calveg (Parker and Mathias, 1977) as provided in a current CDF digital file. We made some assumptions in translating the Calveg types into the Holland types, but we do not expect these assumptions to appreciably affect the results of our analysis.
 

2.2.2 Human Settlement Data
 

These data are 1990 census-based and are for residences onlyÑcommercial and industrial uses would increase the developed area significantly. Thus, the map provides a proxy for where urbanization is occurring in the Sierra Nevada. Housing density was calculated by dividing 100% housing count by the land area of the census blocks. We eliminated the low density classes (<20 dwelling units/square mile). The majority (89%) of housing throughout the Sierra Nevada occurs in densities of 20 units/square mile and greater (Duane, 1996). We chose a threshold value of 1du/32ac to distinguish wildlands from urban-intermix areas. Thus, the five classes used in this report represent only the densities found in urban and urban-intermix areas (Table 2-4). To our knowledge, the forest impacts of areas developed at lower densities have not been quantified by previous authors and are therefore not addressed in this report.
 

Densities are accurate to within 1,000 square meters. Census block boundaries should be within 51 meters of their actual position. Individual census blocks are aggregated into five classes starting with 20-40 dwelling units/square mile and ending with over 640 du/sq.mi. Errors are likely to exist in the largest and most heterogeneous census blocks. This is because census blocks are not evenly distributed across the region. For example, one census block may include areas with two very different densities, yet they are averaged across the block. The occurrence of these errors is low and most census block boundaries should contain relatively homogeneous units (Duane, 1996).
 

Table 2-3: Vegetation Classifications for Data Analysis and Map Displays (Holland, 1986)
 

Table 2-4: Residential Density Classifications
 

2.2.3 Road-Impacted Waterway Data
 

These data were derived from United States Geological Survey (USGS) 100,000 Scale Digital Line Graph (transportation and hydrology) data available from USGS, Menlo Park. The roads were subdivided into groups based on their DLG road labels (USGS, 1993).

· Major Highways: Interstate highways, U.S. Routes, State Routes, County Routes

· Primary and Secondary Routes: (undivided, divided by centerline, divided lanes separated, one way other than divided highway, and class 3 roads and streets)

· Undifferentiated Forest Roads: Class 4 roads and streets; Four-Wheel-Drive Trails.
 

We converted all the roads data to Albers projection and overlaid them onto the SNEP River Basin map and the Hydrologic Sub Areas (HSAs). Then we created a spatial buffer of 150 feet (46 meters) each side of the centerline of a lake, creek or river and analyzed them to determine which roads entered the riparian buffers. This analysis was then overlaid onto forest vegetation in the Sierra Nevada to examine the extent of the problem in forested areas only.
 

The resulting map indexes the possible extent of damage to forest riparian areas caused by roads. Where there is a high density of riparian intrusion by roads, we would expect a smaller network of skid trails to occur on lands managed for timber harvest, as well as Òghost roadsÓ known to exist but not on maps.
 

2.2.4 Data on Fire Return Intervals for Large Fires
 

These data show the expected annual frequency of large (300+ acres) fires on a grid of 10-acre cells as determined by Sapsis and others (1996) for the SNEP report. The areas depicted in the two classes with highest return frequency (1-100 years and 100-250 years) are areas that would be high priority candidates for the reintroduction of fire and other fuel management efforts.
 

The primary data from which these maps were derived are fire history records (39,986 fire records from the period 1981-93). They describe ignition history ratio of large fires to ignitions, and estimates of mean fire size within nine strata. Strata are based on life form (grass, brush, timber, red fir), National Weather Service fire weather zones, and population density class. The resulting fire data and map:

Òare perhaps more reliable for describing current and near term future risk. ...a paucity of fire incidence over substantial areas in the data period could translate into unreasonably low fire frequency estimates for these areas. One should assume that actual fire frequency in areas where fires were scarce in the data period may be higher than the map indicates...We are confident that the relative frequency and regional trends evinced by the map are a reflection of actual likelihood of large fire, and are hence useful information in interpreting risk across the study area.

--Sapsis, et al, 1996.
 

2.2.5 Data on Forest Assets
 

The Sierra Nevada Ecosystem Project was charged with identifying specific high value attributes of Sierra Nevada forests. Teams of scientists were assembled to provide assessments of Late Successional/Old Growth (LS/OG) forests, Giant Sequoia groves, and Ecologically Significant Natural Areas. The assessments were compiled as digital coverages and associated data bases for these important and rare forest features. We secured the digital information on these three types of forest assets from the Alexandria Web Site which serves as a clearinghouse for SNEP data. The maps we produced represent no manipulation of source data other than to overlay our hydrologic boundaries onto the original coverages.
 

2.3 Forest Restoration Goals
 

This assessment of forest restoration needs identifies impacts to Sierra Nevada forests that can be reasonably approached through local restoration strategies. These strategies could include road repair or obliteration, thinning of forests to permit the safe reintroduction of fire, and using fuel management techniques in settled areas that offer maximum protection of biodiversity. An assessment of restoration needs at the scale of actual interventions requires space- and time-specific restoration goals. For example, restoring the role of fire in a 500-acre catchment requires that actual fuel loads be determined, and that the natural fire return interval for that catchment be understood and targeted in pre-treatments (e.g. thinning from below), prescribed burns, and managed wildfires. Similarly, to restore the complexity and diversity of riparian habitat impacted by a forest road, the specific stream flows, needed to erode banks and deposit point bars which in turn permit lateral migration of meandering channels, would need to be estimated and provided. And finally, where the goal of restoring the forest to its condition prior to the arrival of European-American settlers may be appropriate in certain locations, such a target state is no longer feasible in a west slope forest with an extensive human community. From these examples it is clear that both spatial and temporal scales of a finer grain than possible in this regional analysis determine the range of actual treatments.
 

The assessment of forest restoration needs for the entire 20 million acres and 26 major river basins of the Sierra Nevada ecosystem requires that restoration goals be more general. At the regional scale, we define restoration as Òcoordinated actions designed to return an impacted ecosystem to a prior, more natural target stateÓ (Hrubes, 1997), and leave to those who implement restoration at the local scale, the designation of the specific target state and the natural processes to emphasize (e.g. burning, reducing ground fuels, natural pathogens). Restoration needs at the regional scale are then stated more generally in terms of location and quantity of acres of forest or miles of stream that require finer level analysis before specific treatments are selected. This regional analysis serves to focus the work of developing those specific strategies on the areas that need it most.
 

3. FOREST RESTORATION NEEDS BY RIVER BASIN
 

The following analysis of forest restoration needs in the Sierra Nevada specifically examines the effects of human settlement, roads located in riparian areas, and fire suppression. In each case we quantify the area affected based on information available for the whole region. The structure and forests in the Sierra Nevada have been altered by these activities as well as a broad range of other activities from timber harvesting to intensive recreation. The data presented here are therefore not a full accounting of forest impacts in the region. They do however represent the principal problem areas that can reasonably be addressed through the work of forest restoration, and in that sense can be taken as a basis for both prioritizing and for estimating the costs of this work.
 

3.1 Land Protection Status
 

Approximately 65 percent of the Sierra Nevada is under public ownership. The USDA Forest Service alone manages 42 percent of the entire Sierra Nevada ecosystem (Table 3-1). The type of management within each one of these ownerships determines to a great extent the condition of the forests and watersheds in the region. For example, the Bureau of Land Management and USDA Forest Service manage for a variety of uses that range from full wilderness protection to timber production and the condition of these lands reflect this.
 

Table 3-1: Land Ownership in the Sierra Nevada
 

Land Protection Status provides a more meaningful description of land management than simple land ownership can convey. Each class of Land Protection Status profiles both ownership and management and provides a crude measure of risk of development or resource over-exploitation (Davis and Stoms, 1996). Classes distinguish land based on permitted use and assume that the most pervasive land uses affecting the status and trends of terrestrial biodiversity in the Sierra Nevada are grazing, fire suppression, timber harvest, and urban, residential, and agricultural development. The existing management affecting forests of the Sierra Nevada ultimately dictates the options available for forest restoration. For example, restoration on private unprotected forest lands will likely require some mix of incentives and education to promote voluntary action by landowners, whereas restoration on public lands will require in some cases a shift in policy or an augmentation of funds to undertake it, or both.
 

The pattern of protection and ownership mirrors topography somewhat, with greater levels of protection and federal ownership at higher elevation, grading into more vulnerable unprotected private lands at lower elevation (Maps 3a-3e). Central and southern portions of the range have more protected lands than the north. Forests of the Yuba, Truckee, and North Fork American River Basins have a more complex arrangement of protection status, in part due to the checkerboard of public and private lands that remain as a legacy of the disposition of federal lands to transcontinental railroads (Map 4).
 

The five Land Protection Status classes are as follows (Davis and Stoms, 1996):

Class 1 Full Protection

Public or private land formally designated for conservation of native biodiversity and within which timber harvests are precluded. Natural disturbance events are generally allowed to proceed without interference or are mimicked through management. The areas may include national parks, national monuments, ungrazed lands within USDA Forest Service wilderness areas, research natural areas, and wild and scenic rivers, Blue Ridge National Wildlife Refuge, The Nature Conservancy preserves, and state parks and ecological reserves.

Class 2 Mostly Protected--no grazing

National forest land that is generally managed for its natural values but is not formally designated for conservation of native biodiversity. Development and grazing are excluded, and timber harvest is generally excluded because it conflicts with other multiple-use objectives. Wildfires are generally suppressed. The distribution of recreational activities on Class 2 lands is unknown, but a small fraction of the land is developed for recreational facilities.

Class 3 Mostly Protected--some grazing

Public land that is generally managed for its natural values, is treated in existing management plans as unsuitable for timber harvest, and may be grazed. Wildfires may be actively suppressed. Examples include grazing allotments within USFS wilderness areas, grazing allotments on national forest lands classified as unsuitable for timber harvest, the San Joaquin Experimental Range, Bureau of Land Management (BLM) areas of critical environmental concern, and BLM wilderness areas.

Class 4 Other Public Lands

Public lands not included in Classes 1-3, mainly multiple use federal lands managed by the Bureau of Indian Affairs (BIA), Bureau of Reclamation, BLM, and USFS. National forest lands in this category include areas that are classified in existing plans as suitable for timber harvest. These USFS areas can also be within existing grazing allotments. Wildfires are actively suppressed.
 
 

Class 5 Private and Unprotected

Private lands other than those in Class 1. In the absence of more detailed zoning data, we assume that these lands are potentially available for development, timber harvest, and grazing and that wildfires are actively suppressed.
 

3.2 Forest Vegetation
 

Regional forest vegetation maps convey an incomplete picture of a regionÕs forest in that they do not describe the actual ground covered by trees. Anyone who has visited the Sierra Nevada is aware of the great variability in tree density there. Maps assign a forest type to a vast landscape which may actually be treeless in areas up to several acres in size. This is an essential fact to consider when forest vegetation maps are used to quantify the extent of a problem such as the need for forest restoration.
 

The six forest types used in this report include: west-side ponderosa pine, mixed conifer, conifer woodland, other conifers, broadleaf forests, and oak woodlands (see section 2.2.1 for complete descriptions of forest types). Their distribution is shown in Table 3-2.
 

Table 3-2: Acres of Forests in Sierra Nevada River Basins
 

Table 3-3: Acres of Sierran Forest Settled at Densities Greater than

One Dwelling Unit/32 Acres, 1990
 

Table 3-4: Percentage Cover on Undeveloped and Developed Property Associated with Human Settlement (adapted from McBride, Russell and Kloss, 1996)
 

Table 3-5: Extrapolated Decreases in Percentage of Ground Covered by Tree Canopy at Various Lot Densities
 

Table 3-6: Forest Roads Within 150 feet of Riparian Areas in Select Hydrologic Sub-Areas
 

Table 3-7: Forest Roads in Riparian Areas by Land Protection Status (Miles)