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2002 Estimates of Old Growth Forests


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Table of Contents

Title Page and Authors
Abstract
Summary
Introduction
Source Data for Old Growth Estimates
Analysis Methods
Results
Comparison of Current Estimate with Published Reports
Old Growth Tables
References


2002 Estimates of Old Growth Forests
on the 18 National Forests
of the Pacific Southwest Region

Ralph Warbington and Debby Beardsley

An image showing Old Growth trees in a forest in the Pacific Southwest.

US Department of Agriculture, Forest Service, Pacific Southwest Region


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Abstract

Warbington, Ralph; Beardsley, Debby. 2002. 2002 Estimates of Old Growth Forests on the 18 National Forests of the Pacific Southwest Region. USDA Forest Service.

This monitoring report replaces previous estimates of old growth forests for National Forests in the Sierra Nevada and Klamath provinces. Comparisons of old growth forest areas were made of newer and previous estimates. First time estimates were developed for the National Forests in Southern California. Area tables are available by province, National Forest, and forest type.


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Summary

New estimates of old growth conifer forests have been developed for the 18 National Forests in California, which are administered by the Pacific Southwest Region. For the first time, a consistent set of inventory sample plots and vegetation maps were available for obtaining these estimates, on all reserved and non-reserved lands within the National Forests. Vegetation plots, of a standard plot design and data elements, were collected from 1994 to 2000 using a 3.4-mile systematic grid sample framework. Additional plots were collected in rare forest types, using current vegetation maps to identify these areas for more sampling. Dates ranged from 1990 to 1997 for vegetation maps. The maps were developed from 30-meter TM satellite imagery, resource aerial photos and ground visitation, and served as the basis for stratification of all inventory plots. Old growth definitions for eleven conifer forest types were used as the basis for classifying plots as old growth. Productive conifer forest types without old growth definitions were assigned to one of the eleven definitions available. Plot expansion factors from existing vegetation maps formed the basis for estimating acres of old growth by National Forest, reserved and non-reserved lands. No attempt to estimate old growth hardwood forest conditions were made, due to lack of established ecological definitions for hardwood types.


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Introduction

Old growth forests are of increasing importance as they contribute to the overall biodiversity of the National Forests, are key wildlife habitat of late serial dependent species, and store large amounts of carbon which contributes to the slowing of global warming. Historically, reductions in old forest condition were from two main causes, timber harvest and wildfire. Recently, harvest rates have been drastically reduced on the National Forests in California. Changes in land management plans, the Northwest Forest Plan and the Sierra Nevada Framework Plan, have provided land allocation and strategies for protecting the remaining old growth forests in the Region. A similar old growth forest strategy is a likely outcome for the Southern California Forests now under plan revision. Wildfire remains the final threat to the persistence of old growth forests areas on the National Forests.

Monitoring old growth forest conditions will need to continue as the basis for tracking losses and gains in this important natural resource. Permanent plots established through the Forest Inventory and Analysis program of the Forest Service, along with vegetation maps served as the basis of this monitoring report. The re-measurement of these same plots, with associated map updates, provides a continuous monitoring system of all forest conditions on the National Forests. Sampling site productivity, trees and large woody debris by species, size, frequency, and condition allowed for the classification of old growth using existing ecological definitions. This same data set could be used to estimate old growth for hardwood types, if ecological definitions become available.


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Source Data for Old Growth Estimates


List of Source Data Information

Source Data Table
Existing Vegetation Maps
Sample Area of Existing Vegetation Map on the Lassen National Forest
Sample Plots
Number of Forestland Plots Classified for Estimating Old Growth Forest Condition
Lassen National Forest FIA Plot Layout
Linking Sample Plots to Vegetation Maps
Developing a Population Strata Map and Inventory
Sample Area of Strata on the Lassen National Forest



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Source Data Table

Existing vegetation maps and sample plots are the two major components used to estimate old growth forests on the National Forests in the Pacific Southwest Region. For this report, source information ranged from 1990 to 1997 for maps, and 1994 to 2000 for plots. Specific source dates by National Forest are shown in the Table below.

Old Growth Forest Estimates - Source Information
National Forest Vegetation Map * Sample Plots **
Angeles19931995
Cleveland19901995
Eldorado19962000
Inyo19971994
Klamath19941998
Lassen19971999
Los Padres19931996
Mendocino19941997
Modoc19971999
Plumas19972000
San Bernardino19901995
Sequoia19971999
Shasta-Trinity19941998
Sierra19971998
Six Rivers19941997
Stanislaus19971999
Tahoe19972000
Tahoe Basin19971999

* The Vegetation Map date is based on the baseline source imagery date or the latest update date for changes due to fire, harvest, re-growth, and reforestation activities.

** The Sample Plots date is based on when the inventory was completed. Plot installation dates on a Forest range 1-3 years.


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Existing Vegetation Maps

Existing vegetation maps form the basis for acreage estimates for land and water, forest and non-forest land, and defining sample populations for the stratification of ground plots into areas of similar vegetation types, tree sizes and canopy closure classes. The vegetation maps are also used to target additional sample plots for rare forest types and plantations.

Vegetation maps are developed from 30-meter TM imagery, field reconnaissance, map notes, photo editing, image classification for life form and forest size, forest canopy modeling for forest cover and GIS modeling for vegetation typing attributes. The CALVEG classification system is used to describe the floristic type of vegetation. Image segmentation is used to delineate vegetation stands or regions with a minimum mapping unit of 2.5 acres. Water bodies are incorporated from 1:24,000 scale USGS 7.5 minute quadrangle map base series cartographic feature files through GIS integration. Reforestation areas are incorporated from a 1:24,000 scale map of forest plantations based on agency records. Updates for changes are guided by change detection projects using TM imagery from two dates, as well as agency records of forest fires, fuel treatments, harvest, and reforestation activities. The resultant maps are available as a GIS coverage for each National Forest. An example of the existing vegetation map developed for an area on the Lassen National Forest from the process described is shown below.


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Sample Area of Existing Vegetation Map on the Lassen National Forest


An image showing a sample area of the Lassen National Forests Existing Vegetation Map.


More information on the CALVEG classification and mapping program can be found at http://www.fs.fed.us/r5/rsl/projects/mapping/. To obtain existing vegetation GIS map coverages of the National Forests in the Pacific Southwest Region, go to http://www.fs.fed.us/r5/rsl/clearinghouse/forest-eveg.shtml.


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Sample Plots

FIA (Forest Inventory and Analysis) sample plot locations are based on a systematic sample design consisting of cluster plots placed roughly 3.4 miles apart, one plot every 7,400 acres. The FIA grid design was established by the Pacific Northwest Research Station as the basis for sampling all forestlands within the State of California. On National Forest lands in the Pacific Southwest Region, all 3.4-mile sites were installed, on both forest and non-forest lands. Additional plots were installed to sample forest types that had too few samples from the 3.4-mile grid design. This occurs when a particular forest type on a National Forest has fewer than 40,000 acres. The existing vegetation map is used to identify areas of rare forest types, and is the basis for optimally allocating additional intensification ground samples on a 2.4-mile, 1.7-mile, or .85-mile grid within these mapped areas. A sample of 3.4-mile plus intensification plots for the Lassen National Forests is shown in the following graphic.


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Number of Forestland Plots Classified for Estimating Old Growth Forest Condition

National Forest Non-Old Growth Plots Old Growth Plots Total Productive Conifer Forestland Plots Hardwood, Non-Productive and Non-Stocked Forestland Plots Total Forestland Plots on National Forest
Angeles 58 19 77 67 144
Cleveland 40 9 49 28 77
Eldorado 188 30 218 3 221
Inyo 81 60 141 14 155
Klamath 328 35 363 15 378
Lassen 349 32 381 37 418
Los Padres 92 14 106 61 167
Mendocino 169 22 191 21 212
Modoc 261 16 277 21 298
Plumas 296 36 332 12 344
San Bernardino 75 48 123 27 150
Sequoia 180 51 231 36 267
Shasta-Trinity 377 46 423 43 466
Sierra 170 78 248 47 295
Six Rivers 208 35 243 11 254
Stanislaus 183 57 240 19 259
Tahoe 217 26 243 8 251
Tahoe Basin 46 32 78 4 82
Plot Totals 3318 646 3964 474 4438


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Lassen National Forest FIA Plot Layout


An image showing the 1995 Inventory Plots Layout for the Lassen National Forest.

Each cluster plot consists of 5 independent subplots, sampling 2.5 acres and is installed in the field without rotation to avoid different vegetation conditions. If part of a plot crosses a vegetation type, forest size and or forest canopy cover class indicating a change in condition, portions of the cluster plot are assigned to different conditions by mapping, referred to as the mapped plot design. If a change occurred on a cluster plot, mapping was only done between subplots, and not within a subplot. At each subplot measurements of tree frequency, live or dead status, species, diameter, crown ratio, and damages were recorded. A sub-sample of trees was measured for age and height. Understory vegetation life form, species, cover and height as well as ground cover were estimated. Additional samples of down log frequency, species, large end size and length was measured along with estimates of fine forest fuels and fuel bed depth. Further information on the FIA plot design and measurement attributes used in these inventories can be found at http://www.fs.fed.us/r5/rsl/projects/inventory/sampling.shtml.


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Linking Sample Plots to Vegetation Maps

Sample plots were linked to existing vegetation maps by assigning the vegetation map label from the map, where the plot is located. This is done through a GIS overlay of plot locations mapped from GPS and map vegetation polygons. Plots that fall near stand boundaries are reviewed for possible split conditions using aerial resource photos and heads up GIS views of vegetation maps and imagery. If the field installation did not recognize a split condition, then the plot is assigned to only one stand, and one map label. If the field installation mapped two or more conditions, then the best map labels are assigned to each split condition as indicated by the maps, photos and imagery. Approximately 10 percent of the cluster plots sample split conditions, where subplots are assigned to different forest populations in the vegetation map.


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Developing a Population Strata Map and Inventory

Once map labels are assigned to each cluster plot/split condition, post stratification logic is assigned to the existing vegetation map. The goal is to obtain 6 or more cluster plots or 30 or more subplots per vegetation map stratum population to form a statistical sample for each vegetation condition. This in turn allows for estimating the area weight on the map that each sample cluster plot represents in the sample area expansion.

Using the post stratification process of assigning plots to map strata populations results in detailed population estimates of vegetation types, and reduces variance of overall estimates of basal area, number of trees, volume, growth and mortality. This is also useful in habitat modeling and estimating old growth forests since like vegetation types, forest size and condition are key attributes in estimating serial stages of vegetation conditions. The grid systematic sample, while a good design for tracking trends in changes over time, and for sampling common vegetation types and conditions adequately, can completely miss, and often inadequately samples rare forest types and structural conditions. Using vegetation maps to target additional plots compensates for these rare conditions, similar to what can be obtained with a stratified random sample design. Even with intensification, some rare forest types, size and canopy closure combinations have so few acres, they are still missed, and end up lumped into strata of the most similar type or structural condition.

The post stratification process starts with assigning an initial map stratum label to vegetation polygons that have the same life form, most similar floristic type and forest productivity. Some rare forest conditions, even with intensification plots, may have no further stratification for forest size and canopy cover characteristics. If more than 6 cluster plots occur within a general forest type, then forest stand size classes are used to further break out seedling, sapling, and pole sizes from small, medium and large sizes. More detailed breakdown of size classes is done if enough plots area available to do so. Within size classes, further breakdowns based on canopy closure classes of 20 to 50 percent are done, but only if enough plots still exist to create a meaningful statistical estimate. To assure consistent links of plots to a final strata map, all map labels are assigned to strata in a relational data base, and then the same logic is used assign strata labels to the plots, using the linked vegetation map label assigned to each cluster plot/split condition. A vegetation map label to strata crosswalk report is available for each National Forest at http://www.fs.fed.us/r5/rsl/projects/inventory/inv-download.shtml under the column Strata Xwalk. Here is an example report for the Lassen National Forest.

After assigning all map labels to strata labels, a GIS coverage is created by clipping the existing vegetation coverage with an administrative National Forest lands ownership coverage and then dissolving on like strata labels. The result is a simplified strata map where all polygons of the same stratum label represent the area of a vegetation population that is estimated by a set of sample plots with the same stratum label. An example map is shown below.


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Sample Area of Strata on the Lassen National Forest

An image showing a sample area of the Lassen National Forests Strata Map.

For more information on inventory strata maps, refer to the strata layer description found at http://www.fs.fed.us/r5/rsl/projects/frdb/layers/stra.html. For obtaining basic cluster plot data and vegetation inventory reports by plot and strata by Forest, go to http://www.fs.fed.us/r5/rsl/projects/inventory/forest-data.shtml.


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Analysis Methods


List of Analysis Methods Information

Methods for estimating old growth on National Forests
Typing the Plots
Classifying the plots as old growth
SAF Conifer and Conifer/Hardwood mixed types with old growth definitions
SAF Conifer types without old growth definitions
Key to SAF Conifer and Conifer/Hardwood mixed Forest types in California



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Methods for estimating old growth on National Forests

Estimates of total area of forestland as well as total area of reserved, pending reserve, and available forestland were derived from the vegetation maps as described above. Areas were mapped as forestland if they had 10% cover of trees or if they were known to be stocked with trees at some time in the past and have the potential to have 10% cover of trees in the future. Estimates of old growth forestland and estimates of forestland by forest type were derived from the inventory plot expansions. Each plot was assigned an acre expansion depending on its stratum label (area of the stratum divided by the number of plots in the stratum), then typed and assessed for old growth. In our previous published estimates of old-growth in National Forests ("Old-growth Forests in the Sierra Nevada: By Type in 1945 and 1993 and Ownership in 1993", "Old-growth in Northwestern California National Forests") we did not have plots in reserves and had to use the strata maps and extrapolate from the plots outside of wildernesses to estimate old growth in those areas. Our plot sample for the current estimate covered all National Forest forestland, thus, old growth in reserve and available forestland could be estimated with the same methods.


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List of Analysis Methods Information


Typing the Plots

If an inventory plot fell in a polygon mapped as forestland, it was considered forestland. Plots that had at least 10% absolute cover of conifers on it, were typed into one of the Society of American Foresters (SAF) conifer or conifer/hardwood mixed types using the key that follows the list of types below. A plot that had at least 10% cover of conifer but which was dominated by hardwoods might fall in an area mapped as hardwood but be classified as one of the conifer SAF types below because it had at least 10% cover of conifers on it. SAF type 234 (Pacific Douglas-fir/tanoak/madrone) and SAF type 243 (Sierra Nevada mixed conifer), in particular, can sometimes be dominated by hardwoods. A description of SAF forest types is in the Society of American Foresters' "Forest cover types of the US and Canada", edited by F.H. Eyre. In this analysis we used percentages of conifer basal area to type the plots into one of SAF types.

The SAF forest types do not necessarily consist of the same species across all of California. For instance, the Sierra Nevada mixed conifer type in the north may consist of Douglas-fir, white fir, ponderosa pine, incense cedar, black oak, and sugar pine but in the southern forests be dominated by bigcone Douglas-fir, Coulter pine or Jeffrey pine. (See Eyre F.H., Forest cover types of the US and Canada. Society of American Foresters, pages 118-119). Area by SAF type was derived from plot expansions.


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List of Analysis Methods Information


Classifying the plots as old growth

Ecological old-growth definitions have been developed for the major SAF types in California. The purpose of the old-growth definitions was to identify by site class and forest type structural characteristics that indicated the onset of an old-growth stage. (see table 13, page 42 in "Old-growth Forests in the Sierra Nevada: By Type in 1945 and 1993 and Ownership in 1993" and table 12, page 43 in "Old Growth in Northwestern California National Forests" for definitions). However, ecological old growth definitions have not been developed for all the SAF types or for any of the pure hardwood SAF types. We did not assess old growth in the pure hardwood types. For the "other conifers" listed below we used a proxy definition, selecting a type with an old growth definition that would most closely match the form of the trees in a type with an old-growth definition. The table below shows which old-growth definition was used as a proxy for which type. Each of the plots with at least 10% cover in conifer were passed through the old growth algorithms by site class and forest type. Area of old growth by forest type was derived from plot expansions.


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List of Analysis Methods Information


SAF Conifer and Conifer/Hardwood mixed types with old growth definitions

SAF Conifer and Conifer/Hardwood mixed types with old growth definitions
SAF Code SAF Type
207red fir
211white fir
215western white pine (256a, see below)
218lodgepole pine
229Pacific Douglas-fir
231Port Orford-cedar
232redwood
234Douglas-fir-tanoak-Pacifc madrone
237interior ponderosa pine
243Sierra Nevada mixed conifer
245Pacific ponderosa pine
247Jeffrey pine
256California mixed subalpine (this SAF type has 4 separate old growth definitions):
256a       mixed subalpine, western white pine
256b       mixed subalpine, mountain hemlock
256c       mixed subalpine, white fir / Jeffrey pine
256d       mixed subalpine, western juniper
256e       mixed subalpine with aspen



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List of Analysis Methods Information


SAF Conifer types without old growth definitions

SAF conifer types without old growth definitions SAF type for proxy old growth definition
SAF Code SAF Type SAF Code
244Pacific ponderosa pine - Douglas-fir 243
209bristlecone pine256b
219limber pine256b
224western hemlock229
238western juniper256d
239pinyon - juniper256d
248knobcone pine245
250gray pine - blue oak245
260California cypress256d



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List of Analysis Methods Information


Key to SAF Conifer and Conifer/Hardwood Mixed Forest Types in California

  1. If more than 33 percent conifer basal area is redwood, then type is
    SAF 232 redwood.
  2. If more than 33 percent conifer basal area is Port-Orford-cedar, then type is
    SAF 231 Port-Orford-cedar.
  3. If more than 90 percent conifer basal area is western juniper, then type is
    SAF 238 Western juniper.
  4. If more than 25 percent conifer basal area is lodgepole pine and lodgepole pine has the plurality of the basal area stocking of species other than California red fir, then type is
    SAF 218 lodgepole pine.
  5. If more than 80 percent conifer basal area is ponderosa pine and plot is east of the Sierra crest, (in the Modoc, Sierra or Mojave bioregions) then type is
    SAF 237 interior ponderosa pine.
  6. If more than 80 percent conifer basal area is ponderosa pine and plot is west of the Sierra crest, then type is
    SAF 245 Pacific ponderosa pine.
  7. If more than 50 percent conifer basal area is Jeffrey pine, then type is
    SAF 247 Jeffrey pine.
  8. If more than 80 percent conifer basal area is comprised of ponderosa pine and Jeffrey pine:
    !     If plot is east of Sierra crest and there is more ponderosa pine than Jeffrey pine, then type is
    SAF 237 interior ponderosa pine.
    !     If plot is east of Sierra crest and there is more Jeffrey pine than ponderosa pine, then type is
    SAF 247 Jeffrey pine.
    !     If plot is west of Sierra crest and there is more ponderosa pine than Jeffrey pine, then type is
    SAF 245 Pacific ponderosa pine.
    !     If plot is west of Sierra crest and there is more Jeffrey pine than ponderosa pine, then type is
    SAF 247 Jeffrey pine.
  9. If plot consists solely of ponderosa pine and juniper and more than 50 percent conifer basal area is in ponderosa pine, then type is
    SAF 237 interior ponderosa pine.
  10. If more than 50 percent of conifer basal area is white fir and plot is in the Six Rivers National Forest or in the Ukonom, Happy Camp, or west Salmon River districts of the Klamath National Forest, then type is
    SAF 211 white fir-a.
  11. If more than 60 percent of conifer basal area is white fir and plot is NOT in the Six Rivers National Forest or in the Ukonom, Happy Camp, or west Salmon River districts of the Klamath National Forest, then type is
    SAF 211 white fir-b.
  12. If more than 10 percent conifer basal area is comprised of western white pine, whitebark pine, mountain hemlock, aspen, foxtail pine or Brewer spruce:
    !     If more than 60 percent of the conifer basal area is comprised of white fir, California red fir, and Jeffrey pine, then type is
    SAF 256-c mixed subalpine-white fir/Jeffrey pine.
    !     If more than 50 percent of the conifer basal area is comprised of western juniper, then type is
    SAF 256-d mixed subalpine-western juniper.
    !     If more than 50 percent of the conifer basal area is comprised of aspen, then type is
    SAF 256-e mixed subalpine-aspen.
    !     If more than 30% of the conifer basal area is comprised of mountain hemlock, and the mountain hemlock basal area exceeds western white pine, then type is
    SAF 256-b mixed subalpine-mountain hemlock.
    !     If more than 20% of the total basal area is comprised of western white pine, then type is
    SAF 256-a mixed subalpine-western white pine.
    !     If more than 20% of the total basal area is comprised of whitebark pine, then type is
    SAF 208 whitebark pine.
  13. If more than 50% of conifer basal area is California red fir, then the type is
    SAF 207 California red fir.
  14. If more than 80% of conifer basal area is comprised of California red fir and white fir:
    !     If there is more California red fir than white fir, then type is
    SAF 207 California red fir.
    !     If there is more white fir then California red fir and plot is in the Six Rivers National Forest or the Ukonom, Happy Camp, or west Salmon River districts of the Klamath National Forest, then type is
    SAF 211 white fir-a.
    !     If there is more white fir than California red fir and plot is NOT in the Six Rivers National Forest or the Ukonom, Happy Camp, or west Salmon River districts of the Klamath National Forest, then type is
    SAF 211 white fir-b.
  15. If the plot is in the NORTH COAST or SOUTH CENTRAL COAST bioregions and more than 50 percent of conifer basal area is Douglas-fir (or if Douglas-fir is the sole conifer) and evergreen hardwoods (tanoak, Pacific madrone, canyon live oak) comprise at least 10 percent of conifer basal area and white fir is absent, then type is
    SAF 234 Douglas-fir/tanoak.
  16. If the plot is in the NORTH COAST or SOUTH CENTRAL COAST bioregions and more than 50 percent of conifer basal area is Douglas-fir and evergreen hardwoods (tanoak, Pacific madrone, canyon live oak) comprise less than 10 percent of the conifer basal area or white fir is present, then type is
    SAF 229 Pacific Douglas-fir.
  17. If more than 50 percent of the conifer basal area is comprised of a combination of Douglas-fir and ponderosa pine and Douglas-fir conifer basal area is > 20 percent and Ponderosa pine conifer basal areas is >20 percent and white fir is < 10%, then type is
    SAF 244 Pacific ponderosa pine-Douglas-fir.
  18. If redwood or western hemlock or grand fir are present and redwood has the plurality of conifer basal area among these species, then type is
    SAF 232 redwood.
    Else type is
    SAF 224 western hemlock.
  19. If more than 50 percent of the conifer basal area is comprised of a combination of Douglas-fir, ponderosa pine, white fir, incense-cedar, sugar pine, Jeffrey pine, California red fir, giant sequoia, big-cone Douglas-fir or Coulter pine, then type is
    SAF 243 mixed-conifer.
  20. If none of the mixed-conifer species in step 19 are present and the plot has not been assigned to one of the other types in steps 1-19, a plurality of conifer basal area was used:
    A plot with a plurality of conifer basal area in gray pine was typed as
    SAF 250 blue oak-gray pine.
    A plot with a plurality of conifer basal area in knobcone pine was typed as
    SAF 248 closed cone pine.
    A plot with a plurality of conifer basal area in California juniper was typed as
    SAF 239 pinyon juniper.
    A plot with a plurality of conifer basal area in western juniper was typed as
    SAF 238 western juniper.
    A plot with a plurality of conifer basal area in bristlecone pine was typed as
    SAF 209 bristlecone pine.
    A plot with a plurality of conifer basal area in limber pine was typed as
    SAF 219 limber pine.
    A plot with a plurality of conifer basal area in cypress was typed as
    SAF 260 California cypress.


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List of Analysis Methods Information




Results

The current estimates of old growth in National Forests shown in the tables below update and expand previous published estimates of old growth ("Old-growth Forests in the Sierra Nevada: By Type in 1945 and 1993 and Ownership in 1993", "Old Growth in Northwestern California National Forests"). The current estimates are based on the most recent inventory data (1994-2000) and inventory plots which samples all forestland, in and outside of reserves. In addition, these are the first estimates of old growth in the 4 southern National Forests.

We estimate that there are 2.2 million acres of old growth in National Forests in California or 15.7% of the total forestland. The forests with the most old growth are the Sierra, Inyo and the Shasta-Trinity. The majority of the old growth area is in higher-elevation types: red fir, mixed subalpine, lodgepole pine and Jeffrey pine. Over 70% of the lodgepole pine type is old growth. Whereas, the Ponderosa pine, white fir and redwood types have less than 10% of the type in old growth. Sixty percent of the old growth is in "available" forestland and 40% in reserves or pending reserves. The province of California with the greatest area of old growth is the Sierras where about 19% of the forestland is old growth.

The current estimate of old growth in all the Sierra Nevadan National Forests is about 500,000 acres greater than our published report using 1993 data. ("Old-growth Forests in the Sierra Nevada: By Type in 1945 and 1993 and Ownership in 1993"). The biggest increases in the Sierras occurred in the Sierra, Inyo, Plumas, Stanislaus and Eldorado National Forests. The increase in the estimate of old-growth in the Sierra Nevadas is most likely due to two factors: In the published report we extrapolated old-growth area in wildernesses from non-wilderness areas. We noted at the time that this may have underestimated old-growth in wilderness. In addition, the plot size of the plots used in the previous estimate of old growth for the Sierra, Tahoe, Sequoia, Tahoe Basin, Eldorado and Plumas was a 10 point cluster plot covering 10 acres. The current estimate was with a plot size of 5 points covering 2.5 acres. The smaller plot size in the Sierras would tend to "increase" the estimate of old growth because it could pick up smaller patches of old growth. This effect would not necessarily occur in the Klamath province because old growth is less patchy there.


Area of Forestland and Old Growth in Region 5 National Forests by Province
Province Forestland Old Growth Percent old growth forestland
Northcoast/Klamath National Forests 5,142,679 595,960 11.6%
Sierra National Forests 7,752,532 1,477,628 19.1%
Southern National Forests 1,185,892 138,875 11.7%
Total Region 5 National Forests 14,081,103 2,212,463 15.7%


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Comparison of Current Estimate with Published Reports

Northcoast/Klamath Region
Area type Current estimate Northcoast publication (1996) Difference
Forestland 5,142,679 5,155,020 -12,341
Old Growth 595,960 511,594 84,366


Sierra Nevada Region
Area type Current estimate Sierra publication (1999) Difference
Forestland 7,752,532 7,702,660 49,872
  forestland reserved 1,609,825 1,189,675 420,150
  forestland pending 128,569 0 128,569
  forestland available 6,014,139 6,512,985 -498,846 *
Old Growth 1,477,628 924,888 552,740
  old growth reserved 595,346 262,159 333,187
  old growth pending 43,726 0 43,726
  old growth available 838,556 662,730 175,826

* In the published report on old growth in the Sierras, "pending reserve" was included in the "available" class because it is not yet legally reserve.

The biggest increases in the Sierras occurred in the Sierra, Inyo, Plumas, Stanislaus and Eldorado.
The increase in the estimate of old-growth in the Sierra Nevadas is most likely due to two factors:

  1. In the published report we extrapolated old-growth area in wildernesses from non-wilderness areas. We noted at the time that this may have underestimated old-growth in wilderness.
  2. The plot size of the published data for the Sierra, Tahoe, Sequoia, Tahoe Basin, Eldorado and Plumas was a 10 point cluster plot covering 10 acres. The current estimate was with a plot size of 5 points covering 2.5 acres. The smaller plot size in the Sierras would tend to "increase" the estimate of old growth because it could pick up smaller patches of old growth. This effect would not necessarily occur in the Klamath region because old growth is less patchy there.

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Old Growth Tables


List of Tables

Area of forestland and old growth by National Forest and availability.
Area of forestland and old growth in Region 5 National Forests by SAF forest type.
Area of old growth in Region 5 National Forests by SAF forest type and availability class.
Area of old growth by SAF forest type and National Forest.
Angeles National Forest by SAF type.
Cleveland National Forest by SAF type.
Eldorado National Forest by SAF type.
Inyo National Forest by SAF type.
Klamath National Forest by SAF type.
Lassen National Forest by SAF type.
Los Padres National Forest by SAF type.
Mendocinco National Forest by SAF type.
Modoc National Forest by SAF type.
Plumas National Forest by SAF type.
San Bernardino National Forest by SAF type.
Sequoia National Forest by SAF type.
Shasta-Trinity National Forest by SAF type.
Sierra National Forest by SAF type.
Six Rivers National Forest by SAF type.
Stanislaus National Forest by SAF type.
Tahoe National Forest by SAF type.
Tahoe Basin Management Unit by SAF type.
Area of old growth in Region 5 National Forests by elevation.




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Area (in acres) of forestland and old growth by National Forest and availability.

  Available acres Reserved acres * Pending acres ** Total National Forests acres Proportion of Forestland
National Forest Forestland Old Growth Forestland Old Growth Forestland Old Growth Forestland Old Growth that is Old Growth
Angeles 156,573 18,410 51,016 10,280 0 0 207,590 28,690 13.8%
Cleveland 43,252 3,856 6,137 0 0 0 49,389 3,856 7.8%
Eldorado 434,758 91,320 58,444 26,191 19,220 5,385 512,423 122,895 24.0%
Inyo 416,822 117,505 305,088 113,533 42,898 7,298 764,808 238,336 31.2%
Klamath 1,200,147 129,873 351,877 38,422 4,359 0 1,556,384 168,295 10.8%
Lassen 894,759 73,633 65,411 4,186 31,373 14,651 991,543 92,470 9.3%
Los Padres 333,068 10,578 261,158 8,329 10,097 0 604,323 18,907 3.1%
Mendocino 568,448 28,336 124,479 32,187 44 0 692,971 60,523 8.7%
Modoc 883,340 41,414 34,966 1,973 0 0 918,306 43,388 4.7%
Plumas 1,037,434 113,837 56,276 13,203 0 0 1,093,710 127,040 11.6%
San Bernardino 232,498 47,285 92,093 40,137 0 0 324,590 87,422 26.9%
Sequoia 381,656 64,278 513,454 132,121 0 0 895,110 196,399 21.9%
Shasta-Trinity 1,489,377 148,548 470,123 81,588 12,936 0 1,972,435 230,136 11.7%
Sierra 621,427 154,682 423,472 228,279 4 0 1,044,902 382,960 36.7%
Six Rivers 645,671 109,845 275,217 27,161 0 0 920,889 137,006 14.9%
Stanislaus 538,055 57,293 109,297 65,230 35,073 16,392 682,425 138,915 20.4%
Tahoe 693,840 80,916 27,043 2,976 0 0 720,883 83,892 11.6%
Tahoe Basin 112,048 43,679 16,374 7,652 0 0 128,422 51,332 40.0%
Total 10,683,174 1,335,287 3,241,924 833,450 156,005 43,726 14,081,103 2,212,463 15.7%

* Wildernesses or wild and scenic rivers by law.
** Pending legal designation as a wilderness or wild and scenic river.


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Area of forestland and old growth in Region 5 National Forests by SAF forest type.

SAF forest type Acres of Forestland Acres of Old growth Percent of forestland
California mixed subalpine 389,293 109,018 28.0%
Douglas-fir-tanoak-Pacific madrone 974,038 195,442 20.1%
Interior ponderosa pine 491,124 25,186 5.1%
Jeffrey pine 1,086,271 340,467 31.3%
Lodgepole pine 634,930 456,845 72.0%
Pacific Douglas-fir 1,093,186 166,825 15.3%
Pacific ponderosa pine 283,568 0 0.0%
Pacific ponderosa pine-Douglas-fir 480,386 27,170 5.7%
Port Orford-cedar 15,268 12,616 82.6%
Red fir 639,067 254,184 39.8%
Redwood 23,457 1,707 7.3%
Sierra Nevada mixed conifer 3,665,038 476,712 13.0%
Western white pine 8,640 0 0.0%
White fir 1,519,773 124,300 8.2%
Other conifers 786,442 21,992 2.8%
Pure hardwoods 560,879 na na
Hardwood-less than 10% cover of trees 232,999 na na
Conifer-less than 10% cover of trees 982,382 na na
Uninventoried forestland 214,361 na na
Total 14,081,103 2,212,463 15.7% *

* The proportion of forestland that is old growth does not include pure hardwoods or uninventoried forestland. It can be assumed that the non-stocked forestland (less than 10% cover of trees) is not old growth.


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Area of old growth in Region 5 National Forests by SAF forest type and availability class.

SAF forest type Available Acres Reserved Acres Pending Acres Total Acres
California mixed subalpine 32,645 71,242 5,131 109,018
Douglas-fir-tanoak-Pacific madrone 156,968 38,474 0 195,442
Interior ponderosa pine 23,762 1,425 0 25,186
Jeffrey pine 209,961 125,121 5,385 340,467
Lodgepole pine 187,433 268,077 1,335 456,845
Pacific Douglas-fir 142,347 24,478 0 166,825
Pacific ponderosa pine-Douglas-fir 16,796 10,374 0 27,170
Port Orford-cedar 0 12,616 0 12,616
Red fir 146,327 101,315 6,542 254,184
Redwood 0 1,707 0 1,707
Sierra Nevada mixed conifer 333,539 125,138 18,035 476,712
White fir 77,801 46,499 0 124,300
Other conifers 7,708 6,986 7,298 21,992
Total 1,335,287 833,450 43,726 2,212,463

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Area of old growth by SAF forest type and National Forest.

  SAF Forest Type in Acres
National Forest California mixed subalpine Douglas-fir-tanoak-Pacific madrone Interior ponderosa pine Jeffrey pine Lodgepole pine Pacific Douglas-fir Pacific ponderosa pine-Douglas-fir Port Orford-cedar Red fir Redwood Sierra Nevada mixed conifer White fir Other conifer Total
Angeles 0 0 0 11,626 1,997 0 0 0 0 0 14,306 762 0 28,690
Cleveland 0 0 0 3,600 0 0 0 0 0 0 256 0 0 3,856
Eldorado 9,464 0 1,816 5,385 27,865 0 0 0 18,076 0 54,054 6,236 0 122,895
Inyo 6,644 0 0 74,944 128,313 0 0 0 9,881 0 11,257 0 7,298 238,336
Klamath 4,393 60,259 2,046 0 0 41,533 0 5,782 0 0 22,794 31,488 0 168,295
Lassen 1,555 0 3,391 12,403 9,344 0 0 0 10,758 0 46,122 8,896 0 92,470
Los Padres 0 0 0 14,154 0 0 0 0 0 1,557 1,569 1,627 0 18,907
Mendocino 0 8,309 0 4,089 0 10,820 6,115 0 5,056 0 22,890 3,243 0 60,523
Modoc 2,731 0 0 7,313 15,108 0 0 0 2,405 0 10,972 0 4,859 43,388
Plumas 0 0 2,393 24,948 2,072 0 8,326 0 12,358 0 69,920 4,174 2,849 127,040
San Bernardino 0 0 0 34,919 11,995 0 0 0 0 0 27,361 13,148 0 87,422
Sequoia 8,557 0 0 88,829 26,432 0 0 0 40,781 0 27,968 3,832 0 196,399
Shasta-Trinity 4,185 58,177 0 9,792 0 83,558 10,022 0 11,978 0 43,848 8,576 0 230,136
Sierra 22,216 0 3,704 20,371 171,513 0 0 0 83,263 0 54,834 20,073 6,986 382,960
Six Rivers 0 68,697 0 0 0 30,914 2,707 6,834 1,814 149 6,895 18,996 0 137,006
Stanislaus 31,457 0 7,178 10,214 30,278 0 0 0 32,310 0 27,478 0 0 138,915
Tahoe 7,672 0 4,658 4,107 23,835 0 0 0 13,530 0 30,089 0 0 83,892
Tahoe Basin 10,144 0 0 13,773 8,093 0 0 0 11,974 0 4,097 3,250 0 51,332
Total 109,018 195,442 25,186 340,467 456,845 166,825 27,170 12,616 254,184 1,707 476,712 124,300 21,992 2,212,463


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Angeles National Forest by SAF type.

SAF forest type Acres of Forestland Acres of Old growth Percent old growth forestland
Jeffrey pine 18,578 11,626 62.6%
Lodgepole pine 2,626 1,997 76.0%
Pacific Douglas-fir 10,046 0 0.0%
Sierra Nevada mixed conifer 58,805 14,306 24.3%
White fir 11,112 762 6.9%
Other conifer 10,060 0 0.0%
Pure hardwood 31,186 na na
Conifer-less than 10% cover of trees 46,791 na na
Hardwood-less than 10% cover of trees 17,288 na na
Uninventoried forestland 1,098 na na
Total 207,590 28,690 13.8% *

* The proportion of forestland that is old growth does not include pure hardwoods or uninventoried forestland. It can be assumed that the non-stocked forestland (less than 10% cover of trees) is not old growth.


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Cleveland National Forest by SAF type.

SAF forest type Acres of Forestland Acres of Old growth Percent old growth forestland
Jeffrey pine 10,076 3,600 35.7%
Pacific Douglas-fir 1,988 0 0.0%
Sierra Nevada mixed conifer 10,164 256 2.5%
White fir 867 0 0.0%
Pure hardwood 12,263 na na
Conifer-less than 10% cover of trees 4,587 na na
Hardwood-less than 10% cover of trees 9,345 na na
Uninventoried forestland 100 na na
Total 49,389 3,856 7.8% *

* The proportion of forestland that is old growth does not include pure hardwoods or uninventoried forestland. It can be assumed that the non-stocked forestland (less than 10% cover of trees) is not old growth.


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Eldorado National Forest by SAF type.

SAF forest type Acres of Forestland Acres of Old growth Percent old growth forestland
California mixed subalpine 41,590 9,464 22.8%
Interior ponderosa pine 16,207 1,816 11.2%
Jeffrey pine 33,036 5,385 16.3%
Lodgepole pine 48,232 27,865 57.8%
Pacific ponderosa pine 3,536 0 0.0%
Pacific ponderosa pine-Douglas-fir 30,207 0 0.0%
Red fir 27,174 18,076 66.5%
Sierra Nevada mixed conifer 252,691 54,054 21.4%
White fir 41,469 6,236 15.0%
Other conifer 6,391 0 0.0%
Pure hardwood 1,353 na na
Conifer-less than 10% cover of trees 8,369 na na
Uninventoried forestland 2,169 na na
Total 512,423 122,895 24.0% *

* The proportion of forestland that is old growth does not include pure hardwoods or uninventoried forestland. It can be assumed that the non-stocked forestland (less than 10% cover of trees) is not old growth.


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Inyo National Forest by SAF type.

SAF forest type Acres of Forestland Acres of Old growth Percent old growth forestland
California mixed subalpine 75,399 6,644 8.8%
Jeffrey pine 111,079 74,944 67.5%
Lodgepole pine 132,757 128,313 96.7%
Red fir 13,356 9,881 74.0%
Sierra Nevada mixed conifer 28,863 11,257 39.0%
White fir 67,727 0 0.0%
Other conifer 240,281 7,298 3.0%
Pure hardwood 2,746 na na
Conifer-less than 10% cover of trees 74,890 na na
Hardwood-less than 10% cover of trees 15,200 na na
Uninventoried forestland 2,510 na na
Total 764,808 238,336 31.2% *

* The proportion of forestland that is old growth does not include pure hardwoods or uninventoried forestland. It can be assumed that the non-stocked forestland (less than 10% cover of trees) is not old growth.


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Klamath National Forest by SAF type.

SAF forest type Acres of Forestland Acres of Old growth Percent old growth forestland
California mixed subalpine 28,017 4,393 15.7%
Douglas-fir-tanoak-Pacific madrone 281,931 60,259 21.4%
Interior ponderosa pine 4,854 2,046 42.2%
Jeffrey pine 10,198 0 0.0%
Lodgepole pine 10,159 0 0.0%
Pacific Douglas-fir 200,193 41,533 20.7%
Pacific ponderosa pine 86,298 0 0.0%
Pacific ponderosa pine-Douglas-fir 81,841 0 0.0%
Port Orford-cedar 5,782 5,782 100.0%
Red fir 75,982 0 0.0%
Redwood 2,388 0 0.0%
Sierra Nevada mixed conifer 335,087 22,794 6.8%
Western White pine 8,640 0 0.0%
White fir 202,030 31,488 15.6%
Other conifer 13,585 0 0.0%
Pure hardwood 4,207 na na
Conifer-less than 10% cover of trees 113,730 na na
Hardwood-less than 10% cover of trees 14,224 na na
Uninventoried forestland 77,239 na na
Total 1,556,384 168,295 10.8% *

* The proportion of forestland that is old growth does not include pure hardwoods or uninventoried forestland. It can be assumed that the non-stocked forestland (less than 10% cover of trees) is not old growth.


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Lassen National Forest by SAF type.

SAF forest type Acres of Forestland Acres of Old growth Percent old growth forestland
California mixed subalpine 8,814 1,555 17.6%
Interior ponderosa pine 125,779 3,391 2.7%
Jeffrey pine 107,771 12,403 11.5%
Lodgepole pine 48,498 9,344 19.3%
Pacific ponderosa pine-Douglas-fir 7,008 0 0.0%
Red fir 69,112 10,758 15.6%
Sierra Nevada mixed conifer 289,330 46,122 15.9%
White fir 189,725 8,896 4.7%
Other conifer 14,891 0 0.0%
Pure hardwood 16,730 na na
Conifer-less than 10% cover of trees 93,330 na na
Hardwood-less than 10% cover of trees 15,002 na na
Uninventoried forestland 5,551 na na
Total 991,543 92,470 9.3% *

* The proportion of forestland that is old growth does not include pure hardwoods or uninventoried forestland. It can be assumed that the non-stocked forestland (less than 10% cover of trees) is not old growth.


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Los Padres National Forest by SAF type.

SAF forest type Acres of Forestland Acres of Old growth Percent old growth forestland
Jeffrey pine 31,706 14,154 44.6%
Pacific Douglas-fir 4,589 0 0.0%
Pacific ponderosa pine 13,410 0 0.0%
Redwood 13,927 1,557 11.2%
Sierra Nevada mixed conifer 135,201 1,569 1.2%
White fir 5,669 1,627 28.7%
Other conifer 96,138 0 0.0%
Pure hardwood 146,344 na na
Conifer-less than 10% cover of trees 106,431 na na
Hardwood-less than 10% cover of trees 50,172 na na
Uninventoried forestland 735 na na
Total 604,323 18,907 3.1% *

* The proportion of forestland that is old growth does not include pure hardwoods or uninventoried forestland. It can be assumed that the non-stocked forestland (less than 10% cover of trees) is not old growth.


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Mendocinco National Forest by SAF type.

SAF forest type Acres of Forestland Acres of Old growth Percent old growth forestland
Douglas-fir-tanoak-Pacific madrone 96,115 8,309 8.6%
Jeffrey pine 16,753 4,089 24.4%
Pacific Douglas-fir 95,614 10,820 11.3%
Pacific ponderosa pine 44,871 0 0.0%
Pacific ponderosa pine-Douglas-fir 87,298 6,115 7.0%
Red fir 9,337 5,056 54.2%
Sierra Nevada mixed conifer 141,276 22,890 16.2%
White fir 49,885 3,243 6.5%
Other conifer 26,501 0 0.0%
Pure hardwood 36,407 na na
Conifer-less than 10% cover of trees 67,386 na na
Hardwood-less than 10% cover of trees 13,019 na na
Uninventoried forestland 8,508 na na
Total 692,971 60,523 8.7% *

* The proportion of forestland that is old growth does not include pure hardwoods or uninventoried forestland. It can be assumed that the non-stocked forestland (less than 10% cover of trees) is not old growth.


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Modoc National Forest by SAF type.

SAF forest type Acres of Forestland Acres of Old growth Percent old growth forestland
California mixed subalpine 11,823 2,731 23.1%
Interior ponderosa pine 193,116 0 0.0%
Jeffrey pine 98,668 7,313 7.4%
Lodgepole pine 30,988 15,108 48.8%
Pacific ponderosa pine 2,334 0 0.0%
Red fir 6,296 2,405 38.2%
Sierra Nevada mixed conifer 143,815 10,972 7.6%
White fir 118,863 0 0.0%
Other conifer 231,100 4,859 2.1%
Pure hardwood 2,947 na na
Conifer-less than 10% cover of trees 74,120 na na
Uninventoried forestland 4,235 na na
Total 918,306 43,388 4.7% *

* The proportion of forestland that is old growth does not include pure hardwoods or uninventoried forestland. It can be assumed that the non-stocked forestland (less than 10% cover of trees) is not old growth.


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Plumas National Forest by SAF type.

SAF forest type Acres of Forestland Acres of Old growth Percent old growth forestland
California mixed subalpine 7,719 0 0.0%
Interior ponderosa pine 21,041 2,393 11.4%
Jeffrey pine 155,945 24,948 16.0%
Lodgepole pine 13,536 2,072 15.3%
Pacific ponderosa pine-Douglas-fir 98,021 8,326 8.5%
Red fir 44,730 12,358 27.6%
Redwood 6,694 0 0.0%
Sierra Nevada mixed conifer 473,898 69,920 14.8%
White fir 227,113 4,174 1.8%
Other conifer 5,698 2,849 50.0%
Pure hardwood 2,998 na na
Conifer-less than 10% cover of trees 16,587 na na
Hardwood-less than 10% cover of trees 3,220 na na
Uninventoried forestland 16,511 na na
Total 1,093,710 127,040 11.6% *

* The proportion of forestland that is old growth does not include pure hardwoods or uninventoried forestland. It can be assumed that the non-stocked forestland (less than 10% cover of trees) is not old growth.


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San Bernardino National Forest by SAF type.

SAF forest type Acres of Forestland Acres of Old growth Percent old growth forestland
Jeffrey pine 54,084 34,919 64.6%
Lodgepole pine 11,995 11,995 100.0%
Pacific Douglas-fir 3,780 0 0.0%
Pacific ponderosa pine 4,017 0 0.0%
Sierra Nevada mixed conifer 98,623 27,361 27.7%
White fir 29,670 13,148 44.3%
Other conifer 51,287 0 0.0%
Pure hardwood 6,775 na na
Conifer-less than 10% cover of trees 59,598 na na
Hardwood-less than 10% cover of trees 4,742 na na
Uninventoried forestland 18 na na
Total 324,590 87,422 26.9% *

* The proportion of forestland that is old growth does not include pure hardwoods or uninventoried forestland. It can be assumed that the non-stocked forestland (less than 10% cover of trees) is not old growth.


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Sequoia National Forest by SAF type.

SAF forest type Acres of Forestland Acres of Old growth Percent old growth forestland
California mixed subalpine 19,570 8,557 43.7%
Interior ponderosa pine 16,004 0 0.0%
Jeffrey pine 161,226 88,829 55.1%
Lodgepole pine 26,432 26,432 100.0%
Pacific ponderosa pine 1,605 0 0.0%
Red fir 42,997 40,781 94.8%
Sierra Nevada mixed conifer 245,885 27,968 11.4%
White fir 77,712 3,832 4.9%
Other conifer 52,935 0 0.0%
Pure hardwood 73,104 na na
Conifer-less than 10% cover of trees 102,066 na na
Hardwood-less than 10% cover of trees 58,920 na na
Uninventoried forestland 16,654 na na
Total 895,110 196,399 21.9% *

* The proportion of forestland that is old growth does not include pure hardwoods or uninventoried forestland. It can be assumed that the non-stocked forestland (less than 10% cover of trees) is not old growth.


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Shasta-Trinity National Forest by SAF type.

SAF forest type Acres of Forestland Acres of Old growth Percent old growth forestland
California mixed subalpine 23,237 4,185 18.0%
Douglas-fir-tanoak-Pacific madrone 275,500 58,177 21.1%
Jeffrey pine 60,557 9,792 16.2%
Lodgepole pine 22,362 0 0.0%
Pacific Douglas-fir 500,538 83,558 16.7%
Pacific ponderosa pine 126,579 0 0.0%
Pacific ponderosa pine-Douglas-fir 100,975 10,022 9.9%
Red fir 66,198 11,978 18.1%
Sierra Nevada mixed conifer 364,506 43,848 12.0%
White fir 156,681 8,576 5.5%
Other conifer 3,290 0 0.0%
Pure hardwood 71,665 na na
Conifer-less than 10% cover of trees 144,319 na na
Hardwood-less than 10% cover of trees 8,454 na na
Uninventoried forestland 47,574 na na
Total 1,972,435 230,136 11.7% *

* The proportion of forestland that is old growth does not include pure hardwoods or uninventoried forestland. It can be assumed that the non-stocked forestland (less than 10% cover of trees) is not old growth.


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Sierra National Forest by SAF type.

SAF forest type Acres of Forestland Acres of Old growth Percent old growth forestland
California mixed subalpine 36,438 22,216 61.0%
Interior ponderosa pine 42,014 3,704 8.8%
Jeffrey pine 53,789 20,371 37.9%
Lodgepole pine 195,365 171,513 87.8%
Red fir 124,215 83,263 67.0%
Sierra Nevada mixed conifer 341,618 54,834 16.1%
White fir 96,237 20,073 20.9%
Other conifer 28,651 6,986 24.4%
Pure hardwood 91,222 na na
Conifer-less than 10% cover of trees 19,572 na na
Hardwood-less than 10% cover of trees 13,215 na na
Uninventoried forestland 2,566 na na
Total 1,044,902 382,960 36.7% *

* The proportion of forestland that is old growth does not include pure hardwoods or uninventoried forestland. It can be assumed that the non-stocked forestland (less than 10% cover of trees) is not old growth.


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Six Rivers National Forest by SAF type.

SAF forest type Acres of Forestland Acres of Old growth Percent old growth forestland
California mixed subalpine 49,796 0 0.0%
Douglas-fir-tanoak-Pacific madrone 320,491 68,697 21.4%
Jeffrey pine 9,897 0 0.0%
Pacific Douglas-fir 276,439 30,914 11.2%
Pacific ponderosa pine 918 0 0.0%
Pacific ponderosa pine-Douglas-fir 10,438 2,707 25.9%
Port Orford-cedar 9,485 6,834 72.0%
Red fir 11,354 1,814 16.0%
Redwood 448 149 33.3%
Sierra Nevada mixed conifer 109,247 6,895 6.3%
White fir 60,259 18,996 31.5%
Pure hardwood 23,577 na na
Conifer-less than 10% cover of trees 11,936 na na
Hardwood-less than 10% cover of trees 7,348 na na
Uninventoried forestland 19,256 na na
Total 920,889 137,006 14.9% *

* The proportion of forestland that is old growth does not include pure hardwoods or uninventoried forestland. It can be assumed that the non-stocked forestland (less than 10% cover of trees) is not old growth.


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Stanislaus National Forest by SAF type.

SAF forest type Acres of Forestland Acres of Old growth Percent old growth forestland
California mixed subalpine 46,358 31,457 67.9%
Interior ponderosa pine 30,541 7,178 23.5%
Jeffrey pine 25,978 10,214 39.3%
Lodgepole pine 47,412 30,278 63.9%
Pacific ponderosa pine-Douglas-fir 17,340 0 0.0%
Red fir 67,896 32,310 47.6%
Sierra Nevada mixed conifer 304,849 27,478 9.0%
White fir 87,719 0 0.0%
Other conifer 2,244 0 0.0%
Pure hardwood 22,655 na na
Conifer-less than 10% cover of trees 29,716 na na
Hardwood-less than 10% cover of trees 2,849 na na
Total 685,558 138,915 20.3% *

* The proportion of forestland that is old growth does not include pure hardwoods or uninventoried forestland. It can be assumed that the non-stocked forestland (less than 10% cover of trees) is not old growth.


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Tahoe National Forest by SAF type.

SAF forest type Acres of Forestland Acres of Old growth Percent old growth forestland
California mixed subalpine 15,527 7,672 49.4%
Interior ponderosa pine 41,568 4,658 11.2%
Jeffrey pine 105,214 4,107 3.9%
Lodgepole pine 32,170 23,835 74.1%
Pacific ponderosa pine-Douglas-fir 47,258 0 0.0%
Red fir 54,103 13,530 25.0%
Sierra Nevada mixed conifer 313,993 30,089 9.6%
White fir 80,624 0 0.0%
Other conifer 1,404 0 0.0%
Pure hardwood 14,699 na na
Conifer-less than 10% cover of trees 1,980 na na
Uninventoried forestland 12,343 na na
Total 720,883 83,892 11.6% *

* The proportion of forestland that is old growth does not include pure hardwoods or uninventoried forestland. It can be assumed that the non-stocked forestland (less than 10% cover of trees) is not old growth.


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Tahoe Basin Management Unit by SAF type.

SAF forest type Acres of Forestland Acres of Old growth Percent old growth forestland
California mixed subalpine 25,006 10,144 40.6%
Jeffrey pine 21,717 13,773 63.4%
Lodgepole pine 12,398 8,093 65.3%
Red fir 26,320 11,974 45.5%
Sierra Nevada mixed conifer 17,188 4,097 23.8%
White fir 16,410 3,250 19.8%
Other conifer 1,985 0 0.0%
Conifer-less than 10% cover of trees 6,971 na na
Uninventoried forestland 427 na na
Total 128,422 51,332 40.0% *

* The proportion of forestland that is old growth does not include pure hardwoods or uninventoried forestland. It can be assumed that the non-stocked forestland (less than 10% cover of trees) is not old growth.


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Area of old growth in Region 5 National Forests by elevation.

Elevation in feet Acres of Old growth Percent total old growth
< 1,000 9,829 0%
1,000-1,999 19,850 1%
2,000-2,999 104,885 5%
3,000-3,999 228,671 10%
4,000-4,999 209,647 9%
5,000-5,999 291,015 13%
6,000-6,999 254,667 12%
7,000-7,999 355,730 16%
8,000-8,999 410,308 19%
9,000-9,999 266,031 12%
> 10,000 61,831 3%
  Total acres    2,212,463  


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References

Beardsley, Debby; Bolsinger, Charles; Warbington, Ralph. 1999. Old-growth forests in the Sierra Nevada: by type in 1945 and 1993 and ownership in 1993. Res. Pap. PNW-RP-516. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 46 p.

Beardsley, Debby; Warbington, Ralph. 1996. Old Growth in Northwestern California National Forests. Res. Pap. PNW RP-491. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 47 p.

Bolsinger, Charles L.; Waddell, Karen L. 1993. Area of old-growth forests in California, Oregon, and Washington. Resource. Bull. PNW-RB-197. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 26 p.

Brown, Page. 1998. Climate, Biodiversity, and Forests: Issues and Opportunities Emerging from the Kyoto Protocol. ISBN Number 1-56973-285-x. World Resources Institute, 10 G Street, NE (Suite 800), Washington, DC. 40p.

Eyre, Et-t., ed. 1980. Forest Cover Types of the United States and Canada. Washington, DC: Society of American Foresters. 148 p.

Fites, Jo Ann; Chapel, M.; Corbin, B. [and others]. 1991 a. Preliminary ecological old-growth definitions for mixed-conifer (SAF type 243) in California. Unpublished report, old-growth-define.pdf . U.S. Department of Agriculture, Forest Service, Pacific Southwest Region.

Fites, Jo Arm; Chapel, M.; Corbin, B. [and others]. 1991 b. Preliminary ecological old-growth definitions for white fir (SAF type 211) in California. Unpublished report, old-growth-define.pdf . U.S. Department of Agriculture, Forest Service, Pacific Southwest Region.

Fites-Kaufmann, Jo Ann; Franklin, Jerry F. 1996. Assessment of late-successional forests of the Sierra Nevada. In: Sierra Nevada ecosystem project, final report to Congress, vol. II, assessments and scientific basis for management options. Davis: University of California, Centers for Water and Wildland Resources: 627-662.

Hemstrom, Miles; Spies, Thomas; Palmer, Craig; Kiester, Ross; Teply, John; McDonald, Phil; and Warbington, Ralph. 1998. Late-successional and old-growth forest effectiveness monitoring plan for the Northwest Forest Plan. Gen. Tech. Rep. PNW-GTR-438. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 37 p.

Jimerson,T.; Bingham, B.; Solis, D.; Macmeeken, S. 199la. Ecological definition for old-growth Douglas-fir/tanoakIPacific madrone (SAF 234). Unpublished report, old-growth-define.pdf . U.S. Department of Agriculture, Forest Service, Pacific Southwest Region.

Jimerson,T.; Bingham, B.; Solis, D.; Macaneeken, S. 1991b. Ecological definition for old-growth Pacific Douglas-fir (SAF 229). Unpublished report, old-growth-define.pdf . U.S. Department of Agriculture, Forest Service, Pacific Southwest Region.

Old-Growth DefinitionTask Group. 1986. Interim definitions for old-growth Douglas-fir and mixed-conifer forests in the Pacific Northwest and California. Res. Note PNW-447. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 7 p.

Northwest Forest Plan, Record of Decision for Amendments to Forest Service and Bureau of Land Management Planning Documents within the Range of the Northern Spotted Owl. 1994. U.S. Department of Agriculture and U.S. Department of Interior. 74 p.

Northwest Forest Plan, Standards and Guidelines for Management of the Habitat for Late-Successional and Old-Growth Forest Related Species within the Range of the Northern Spotted Owl. Attachment A, ROD for Amendments to the Forest Service and BLM Planning Documents. 1994. U.S. Department of Agriculture and U.S. Department of Interior. 153 p.

Potter, D.; Smith, M.; Beck, T. [and others]. 1992a. Ecological characteristics of old-growth California mixed-subalpine forests. Unpublished report, old-growth-define.pdf . U.S. Department of Agriculture, Forest Service, Pacific Southwest Region.

Potter, D.; Smith, M.; Beck,T. [and others]. 1992b. Ecological characteristics of old-growth Jeffrey pine in California. Unpublished report, old-growth-define.pdf . U.S. Department of Agriculture, Forest Service, Pacific Southwest Region.

Potter, D.; Smith, M.; Beck,T. [and others]. 1992c. Ecological characteristics of old-growth lodgepole pine in California. Unpublished report, old-growth-define.pdf . U.S. Department of Agriculture, Forest Service, Pacific Southwest Region.

Potter, D.; Smith, M.; Beck,T. [and others]. 1992d. Ecological characteristics of old-growth red fir in California. Unpublished report, old-growth-define.pdf . U.S. Department of Agriculture, Forest Service, Pacific Southwest Region.

Sierra Nevada Forest Plan Amendment Record of Decision. 2001. U.S. Department of Agriculture, Pacific Southwest Region and Intermountain Region. 55 p.

Smith, S.; Laudenslayer, W.;Trask, J.; Armijo, M. 1991. Interim guidelines defining old-growth stands: Pacific ponderosa pine (SAF 245). Unpublished report, old-growth-define.pdf . U.S. Department of Agriculture, Forest Service, Pacific Southwest Region.

Smith, Sydney. 1991. Revised interim old-growth definitions for interior ponderosa pine (SAF 237). Unpublished report, old-growth-define.pdf . U.S. Department of Agriculture, Forest Service, Pacific Southwest Region.

Southern California National Forests, Notice of Intent, Proposed Action. 2001. U.S. Department of Agriculture, Forest Service, Pacific Southwest Region . 126 p.

U. S. Department of Agriculture, Forest Service, 1981. CALVEG: a classification of California vegetation, San Francisco, CA: Regional Ecology Group. U.S. Department of Agriculture, Forest Service.

U. S. Department of Agriculture, Forest Service, 2000. CALVEG Geobook, CDROM. On file with: Remote Sensing Laboratory, U.S. Department of Agriculture, Forest Service, Pacific Southwest Region, Sacramento, CA 95814.

U. S. Department of Agriculture, Forest Service, 2000. Forest Inventory and Analysis User's Guide. Unpublished document. On file with: Remote Sensing Laboratory, U.S. Department of Agriculture, Forest Service, Pacific Southwest Region, Sacramento, CA 95814.

Verner, Jared; McKelvey, Leven S.; Noon, Barry R. [and others], tech. coords. 1992. The California spotted owl: a technical assessment of its current status. Gen. Tech. Report, PSW-gtr-133. Albany, CA. U.S. Department of Agriculture, Forest Service, Pacific Southwest Research Station. 285 p.


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USDA Forest Service · Pacific Southwest Region