United States

Department of 

Agriculture

Forest 

Service

Pacific Northwest

Research Station

Timber Resource 

Statistics of South-Central

Alaska, 2003

Willem W.S. van Hees

Resource Bulletin

PNW-RB-248

June 2005
The Forest Service of the U.S. Department of Agriculture is dedicated to the principle of

multiple use management of the Nation’s forest resources for sustained yields of wood,

water, forage, wildlife, and recreation. Through forestry research, cooperation with the

States and private forest owners, and management of the National Forests and National

Grasslands, it strives—as directed by Congress—to provide increasingly greater service to 

a growing Nation.

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or call (202) 720-5964 (voice or TDD). USDA is an equal opportunity provider and employer.

USDA is committed to making its information materials accessible to all USDA customers

and employees.

Author

Willem W.S. van Hees is a research forester, Forestry Sciences Laboratory, 

3301 C St., Suite 200, Anchorage, AK 99503.
Timber Resource Statistics of South-Central Alaska, 2003

Abstract

van Hees, Willem W.S. 2005. Timber resource statistics of south-central Alaska, 

2003. Resour. Bull. PNW-RB-248. Portland, OR: U.S. Department of

Agriculture, Forest Service, Pacific Northwest Research Station. 24 p.

Estimates of timber resources for south-central Alaska are presented. Data collection began in 2000 and was completed in 2003. All forest lands over all ownerships were considered for sampling. The inventory unit was, roughly, the region

between Icy Bay to the east and Kodiak Island to the west. Forest lands within

national forest wilderness study areas and recommended wilderness areas were not

sampled on the ground. Tables present supply estimates of area, timber volume,

growth, mortality, and harvest.

Keywords: Forest surveys, timber resources, statistics (forest), Alaska (south-central).

Summary

The south-central Alaska inventory unit covers approximately 18.5 million acres.

Slightly over one-fifth of this area is forested, about 4.0 million acres. Nearly 1.3

million acres (32 percent) of the forested total is reserved from timber management.

Timberland, that portion of the total forest land base that is potentially available

for timber management and is capable of producing at least 20 ft3 of wood per acre

per year at culmination of mean annual increment, composes 46 percent (1.9 million

acres) of the forest and 10 percent of the total land base. Most tabulated estimates

presented in this report are for timberland forests. 

Most timberland (74 percent) is owned by the state of Alaska and various

private owners; the remainder is federally managed. The dominant forest type on

timberland is Sitka spruce (37 percent) followed by paper birch (17 percent), white

spruce (14 percent) and mixed conifer (10 percent). Net volume on timberland is

estimated at 5.1 billion ft3

. Gross average annual growth was estimated at 63.7

million ft3 and average annual mortality at 72.4 million ft3. Average net annual

growth was negative, with a loss of 8.8 million cubic feet per year. Other data

showed harvest volumes from 1997 to 2001 ranged from a high of 248 million

board feet in 1997 to a low of 58.4 million board feet in 2000. 
Resource Bulletin PNW-RB-248

Preface

Forest Inventory and Analysis (FIA) is a nationwide program of the USDA Forest

Service authorized by the Forest and Rangeland Renewable Resources Act of 1978.

Work units, located at Forest Service research stations, conduct forest resource

inventories throughout the 50 states. The FIA Program of the Pacific Northwest

Research Station in Portland, Oregon, is responsible for forest inventories in Alaska,

California, Oregon, Washington, Hawaii, and the Pacific Trust Islands.
Timber Resource Statistics of South-Central Alaska, 2003

Contents

1 Introduction

2 Inventory Procedures

4 Reliability of Inventory Data

4 Terminology

8 Names of Trees

8 Acknowledgments

9 Metric Equivalents

9 Literature Cited

List of Tables

Table 1—Estimated area by land class, owner group, and reserved component,

south-central Alaska, 2003

Table 2—Estimated area of forest land by owner group, reserved status, and forest

type, south-central Alaska, 2003 

Table 3—Estimated area of timberland by owner group and forest type, southcentral Alaska, 2003 

Table 4—Estimated area of timberland by owner group and stand size class, southcentral Alaska, 2003 

Table 5—Estimated area of timberland by owner group and cubic-foot site class,

south-central Alaska, 2003

Table 6—Estimated area of timberland by forest type and stand-size class, southcentral Alaska, 2003

Table 7—Estimated number of growing-stock trees on timberland by species and

diameter class, south-central Alaska, 2003

Table 8—Estimated net volume of growing stock and sawtimber on timberland 

by class of timber, owner group, and species group, south-central Alaska, 2003

Table 9—Estimated net volume of growing stock on timberland by species and

diameter class, south-central Alaska, 2003

Table 10—Estimated net volume of sawtimber on timberland by species and 

diameter class, south-central Alaska, 2003
Resource Bulletin PNW-RB-248

Table 11—Estimated net volume of growing stock on timberland by species and

owner group, south-central Alaska, 2003

Table 12—Estimated net volume of sawtimber on timberland by species and owner

group, south-central Alaska, 2003

Table 13—Estimated net volume of growing stock on timberland by forest type

and stand-size class, south-central Alaska, 2003

Table 14—Estimated net volume of sawtimber on timberland by forest type and

stand-size class, south-central Alaska, 2003

Table 15—Estimated net volume of growing stock on timberland by forest type

and owner group, south-central Alaska, 2003

Table 16—Estimated net volume of sawtimber on timberland by forest type and

owner group, south-central Alaska, 2003

Table 17—Estimated current average gross annual growth of growing stock on 

timberland by owner group and species group, south-central Alaska, 2003

Table 18—Estimated current average net annual growth of growing stock on 

timberland by forest type and owner group, south-central Alaska, 2003

Table 19—Estimated current average net annual growth of sawtimber on timberland by forest type and owner group, south-central Alaska, 2003

Table 20—Estimated average annual mortality of growing stock on timberland by

forest type and owner group, south-central Alaska, 2003

Table 21—Estimated average annual mortality of sawtimber on timberland by 

forest type and owner group, south-central Alaska, 2003

Table 22—Estimated timber harvest volume (scaled postharvest) by year and

owner group, south-central Alaska, 1988 to 2001

Table 23—Standard errors of selected inventory estimates, south-central Alaska,

2003

Table 24—Approximate confidence intervals for timberland area and growingstock volume estimates of varying magnitudes, south-central Alaska, 2003
Highlights 

Land cover

Thousand acres Thousand ha

South-central inventory area:

Forest land—

Timberland 1,875 759

Other forest 2,169 878

Total forest 4,044 1637

Nonforest land 14,435 5842

Total 18,480 7479

Timberland composition:

Softwoods—

Black spruce 24 10

Mixed conifer 196 79

Mountain hemlock 105 43

Sitka spruce 695 281

Western hemlock 121 49

White spruce 260 105

Total softwoods 1,402 567

Hardwoods—

Aspen 13 5

Paper birch 319 129

Poplar 141 57

Total hardwoods 474 192

Volumes on timberland

Growing stock Sawtimber

Thousand Thousand Thousand Thousand

ft3 a m

3 a board feet b m3 c

Net volume 5,086,954 144 046 20,120,713 130 914

Average gross annual growth 63,673 1803 204,546 1204

Annual mortality 72,441 2051 218,026 1832

a Net volume of roundwood for growing-stock trees 5.0 in d.b.h. and larger.

b Net volume, Scribner rule, for softwood trees 9.0 in and larger and for hardwood trees 11.0 

in d.b.h. and larger.

c Net volume of roundwood for softwood trees 9.0 in and larger and for hardwood trees 11.0 

in d.b.h. and larger.

Timber Resource Statistics of South-Central Alaska, 2003
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Timber Resource Statistics of South-Central Alaska, 2003

1

Introduction 

The inventory of south-central Alaska was conducted between 2000 and 2003 by

the Forest Inventory and Analysis (FIA) Program of the Pacific Northwest Research

Station. This effort was the first inventory of the region using a consistent sample

design. The inventory unit is depicted in figure 1. 

Ecologically, the inventory unit is diverse; it contains all or part of four ecoregions (fig. 2). These ecoregions are Kodiak Island, the Cook Inlet Basin, the

Chugach–St. Elias Mountains, and the Gulf of Alaska coast regions.

The Kodiak Island ecoregion is a geologic extension of the Chugach Mountains

with a cool, wet maritime climate. This island group includes high peaks, low rounded

ridges, and glacially scoured valleys with till or lacustrine soils entirely free of permafrost. Floral communities are relatively new because the last Pleistocene glaciation

scoured the islands. Sitka spruce and black cottonwood (see “Names of Trees” for

scientific names of trees mentioned in this publication) forests are present, particularly in northern areas of the region, but forb/grass meadows and willow (Salix spp.)

and alder (Alnus spp.) thickets are otherwise dominant. Some alpine tundra exists

at higher elevations. 

The Cook Inlet Basin is characterized by a mixed continental and maritime

climate, level to rolling topography, and soil generally free from permafrost.

Vegetation includes black spruce forests, ericaceous shrubs in open bogs, mixed

forests of white and Sitka spruce, aspen and birch on better drained sites, and tall

shrub communities of willow and alder on slopes along the periphery of the basin. 

Steep, rugged topography and a transitional climate typify the Chugach–St.

Elias Mountain region. This region is largely barren of vegetation. Mountain summits and slopes without permanent ice and snow have thin and rocky soils supporting alpine communities of sedges, grasses, and low shrubs. Where glaciers and ice

fields have receded, broad U-shaped valleys have deeper soils with isolated pockets

of permafrost. Along valley bottoms and lower valley slopes, alder shrublands and

mixed forests are present. 

The Gulf of Alaska Coast region contains deep narrow bays, steep valley walls,

and irregular coastlines with glacial moraine deposits on lower slopes in central

and western areas of the region. Eastern areas of the region contain coastal forelands with unconsolidated glacial, alluvial, and marine deposits. The maritime

climate has abundant precipitation, and permafrost is absent. Temperate rain forests

of Sitka spruce, western hemlock, and mountain hemlock are found sporadically

near sea level where soil drainage is sufficient (Nowacki and others 2001).
Resource Bulletin PNW-RB-248

2

Inventory Procedures

The inventory of forest resources in south-central coastal Alaska used a singlephase, unstratified systematic-grid sample with grid spacing of 3 mi. Ground plots

were established at each grid intersection. Sampling intensity was chosen to meet

sampling error guidelines of ±3 percent per million acres for productive forest area

and ±10 percent per billion cubic feet for net volume. 

Land cover was visually interpreted for each plot by using high-resolution

orthophotoquads and high-resolution satellite imagery. Plots that were barren or

covered with ice and snow were not visited on the ground. On national forest lands,

all vegetated plots were ground visited; on other lands, only forested plots were

Figure 1—South-central Alaska inventory unit, 2003.
Timber Resource Statistics of South-Central Alaska, 2003

3

visited. Ground plots consisted of a cluster of four, 24-ft fixed-radius subplots.

From the first centrally located subplot, three other subplots were located 120 ft

north, southeast, and southwest, respectively. Each subplot was mapped for land

cover. Field plot design is detailed in Scott and Bechtold (1995).

Trees, if present, were sampled at each of the four subplots. Seedlings and

saplings also were sampled, but with a 6.8-ft fixed-radius microplot at each subplot.

Data collection procedures are described in USDA Forest Service (2000-2003).

Estimation of components of tree volume change, such as growth and mortality,

is relatively straightforward in remeasurement inventories. However, in an initial

inventory such as the one for which results are presented in this report, these

observations are unavailable. For this inventory, field crews measured 10-year

Figure 2— Ecoregions of south-central Alaska (Nowacki and others 2001).
Resource Bulletin PNW-RB-248

4

radial increment, at breast height, on the first live, growing-stock, tally tree (≥5 in

diameter at breast height [d.b.h.]) of each species in each 2-in d.b.h. class. These

measurements were used to develop models expressing radial growth rate as a

function of d.b.h., crown length, and crown radius. Similarly, changes in tree height

were estimated from models relating tree diameter to tree height (USDA 1998).

Estimation of tree mortality relied on estimation of the time since death for dead

trees on the plot. Using guides to estimate time since death, field crews determined

if the tree had died more than 5 years or less than or equal to 5 years, prior to date

of inventory. Trees that had died within the previous 5 years were used to estimate

average annual mortality volumes. Volumes lost to harvest are not included in estimates of mortality presented here.

In all, 2,891 plots were located within south-central Alaska. Of these plots, 439

had some productive forest on them. About one-fourth (782) of the locations had

some forested land cover whether productive, nonproductive, or inaccessible forest. 

Reliability of Inventory Data

Estimates presented in this report are based on sampling and are subject to three

types of error. The first is sampling error. This type of error can be estimated mathematically. The second type of error arises from measurement mistakes or equipment

limitations. The second error cannot be estimated mathematically but is minimized

through proper training, supervision, emphasis on careful work, and a program of

quality assurance and control. The third type of error arises from modeling error.

This type of error arises from calculating attributes that are not directly measured,

such as growth, mortality, and harvest. The reliability of the inventory is expressed

as relative sampling error at the 68 percent confidence level. Estimates of sampling

error and approximate confidence intervals are provided in tables 23 and 24. Figures

presented in table 24 were developed by using the following relation:

Target estimated error percent = (percent sampling error of inventory estimate)*

[(inventory estimate)0.5/(target estimate) 0.5] (Alerich and others 2004).

Terminology

average annual mortality—The number of or the sound wood volume from live 

trees dying from natural causes during a specified period. For this inventory, the

period was 5 years prior to field measurement.

average gross annual growth—The average annual increase in volume of wood for

growing-stock trees during a specified period. Components of average gross annual
Timber Resource Statistics of South-Central Alaska, 2003

5

growth are the increment in net volume of trees alive at the beginning of the specified period plus the net volume of trees reaching sawtimber or poletimber size during the period. Average annual growth was modeled by using 10-year radial increment

cores. Average net annual growth is average gross annual growth minus the average

net volume of trees that died and minus the average volume lost to tree decay.

Volume losses were averaged over the 5 years prior to date of field measurement. 

cull trees—Live trees of sawtimber or poletimber size that are not merchantable for 

saw logs and are unlikely to become merchantable because of defect, rot, or species.

diameter class—A classification of trees based on diameter at breast height (d.b.h.),

4.5 ft above the ground, outside bark. Each 2-in diameter class is assigned to the

appropriate even inch at midpoint. For example, the 6-in class includes trees 5.0

through 6.9 in d.b.h.

forest land—Land at least 16.7-percent stocked by live trees of any size, or land 

formerly having such tree cover and not currently developed for nonforest use. The

minimum area for classification as forest land or subclasses of forest land is 1 acre.

Roadside, streamside, and shelterbelt strips of timber must be at least 120 ft wide

to be classified as forest land. Unimproved roads and trails, streams, and clearings

in forest areas must be less than 120 ft wide to be classified as forest land. (Also

see timberland, other forest land, reserved forest land, and nonforest land.)

forest types—A classification of forest land based on the tree species stocking on 

the area currently occupied by tree cover.

softwoods:

black spruce—Forests in which black spruce stocking is greater than 65 

percent of the softwood tree stocking.

mixed conifer—Forests in which the sum of all softwood stocking is greater 

than 50 percent of the tree stocking but no individual softwood species meets

any of the minimum stocking levels to define a single-species forest type.

mountain hemlock—Forests in which mountain hemlock stocking is greater 

than 65 percent of the softwood tree stocking.

Sitka spruce—Forests in which Sitka spruce stocking is greater than 75 

percent of the softwood tree stocking.

western hemlock—Forests in which western hemlock stocking is greater than 

60 percent of the softwood tree stocking.
Resource Bulletin PNW-RB-248

6

white spruce—Forests in which white spruce stocking is greater than 50 

percent of the softwood tree stocking.

hardwoods:

aspen—Forests in which aspen stocking is greater than 30 percent of the hardwood tree stocking.

paper birch—Forests in which paper birch stocking is greater than 30 percent 

of the hardwood tree stocking.

poplar—Forests in which poplar stocking is greater than 30 percent of the 

hardwood tree stocking.

growing-stock trees—All live trees except cull trees.

growing-stock volume—Net volume in cubic feet of live sawtimber and poletimber growing-stock trees from stump to a minimum 4.0-in top (of central stem)

outside the bark. Net volume equals gross volume less deductions for rot and 

missing bole sections.

land class—A classification of land by forest cover, such as timberland, other 

forest, or nonforest. The minimum area for classification is 1 acre.

mean annual increment (m.a.i.)—A measure of the productivity of forest land 

in terms of the average increase in volume in cubic feet per acre per year.

net volume—The gross volume of a tree less deductions for rot, sweep, or other 

defect affecting product use.

nonforest land—Land that does not qualify as forest land. Nonforest land includes 

land that has never supported forest and land formerly forested where forest use is

precluded by development for nonforest uses. Included is land used for agricultural

crops, improved pasture, residential areas, city parks, improved roads, operating

railroads and their right-of-way clearings, and pipeline clearings. If intermingled in

forest areas, unimproved roads, streams, canals, and nonforest strips must be more

than 120 ft wide, and clearings or other areas must be 1 acre or larger to qualify as

nonforest land.

other forest land—Forest land not capable of producing 20 ft3

per acre per year 

or more of wood at culmination of m.a.i. or withdrawn from timber use owing to

administrative statute.
7

Timber Resource Statistics of South-Central Alaska, 2003

poletimber stands—Stands at least 16.7-percent stocked with growing-stock 

trees, with one-half or more of this stocking in poletimber and sawtimber trees, and

with poletimber stocking exceeding that of sawtimber.

poletimber trees—Growing-stock trees greater than 5.0 in d.b.h. and less

than sawtimber size.

productive forest land—Forest land producing or capable of producing 20 ft3

per acre per year or more of wood at culmination of m.a.i.

reserved forest land—Forest land withdrawn from timber use through statute 

or administrative regulation.

sawtimber stands—Stands at least 16.7-percent stocked with growing-stock 

trees, with half or more of this stocking in sawtimber or poletimber trees, and with

sawtimber stocking at least equal to that of poletimber.

sawtimber trees—Growing-stock trees at least 11.0 in d.b.h. for hardwoods 

and 9.0 in for softwoods.

seedling and sapling stands—Stands at least 16.7-percent stocked with 

growing-stock trees and with saplings or seedlings composing more than half this

stocking.

seedling and sapling trees—Growing-stock trees less than 1.0 in d.b.h. for 

seedlings and 1.0 to 4.9 in d.b.h. for saplings.

site class—A classification of forest land based on its capacity to grow wood.

stand size class—A classification of forest land based on the predominant

size of timber present: sawtimber, poletimber, or seedlings and saplings.

stocking—A measure of the area occupied by trees of specified classes. The 

FIA forest inventories consider three categories of stocking: all live trees, growingstock trees, and desirable trees. Stocking of all live trees is used to delineate forest

land and forest types. Stocking of growing-stock trees is used in classifications of

stand size and stand age.

timberland—Productive forest land not withdrawn from timber use by 

administrative statute. 
8

Resource Bulletin PNW-RB-248

Names of Trees4

Common name Scientific name

Softwoods:

Black spruce Picea mariana (Mill.) B.S.P.

Mountain hemlock Tsuga mertensiana (Bong.) Carr.

Sitka spruce Picea sitchensis (Bong.) Carr.

Western hemlock Tsuga heterophylla (Raf.) Sarg.

White spruce Picea glauca (Moench) Voss 

Hardwoods:

Black cottonwood (poplar) Populus trichocarpa Torr. & Gray

Paper birch Betula papyrifera Marsh.

Quaking aspen Populus tremuloides Michx.

Acknowledgments

Successful design and completion of this inventory depended on the efforts of many

people. Special thanks go to the many landowners who allowed access to their lands

for data collection. Thanks go to Ray Koleser, data collection team leader, and the

data collection staff Stacy Allen, Sheel Bansal, DeAnna Barbaria, Mathew Barmann,

Aaron Bergdahl, Tina Boucher, Will Bunten, Whitney Burgess, Carey Carmichael,

Brian Charlton, Ian Doleman, Jason Downing, Jason Edney, Walter Foss, Christa

Gulaian, Tracy Hart, Ken Hehr, Connie Hubbard, Christopher Jansen, John Kelley,

Tristan Kelley, H. Lewis, Lisa Mahal, Joel Markis, Jeff Matthews, D. McInnis,

Rachel Morse, Eric Murphy, Shawn Osborn, Frank Pendleton, Mike Pond, Ashley

Reed, Bob Rhoads, Sadie Rosenthal, Lynn Sainsbury, Tom Salzer, Sasha Sulia,

Andy Tasler, Chris Teutsch, Donald Tintle, Michael West, Sue Willits, Misha Yatskov,

and Steven Voelker. Thanks also to Kevin Dobelbower for database development

and field data recorder and compilation programming, and to Kenneth Winterberger

for remote sensing and geographic information systems support.

4 Scientific names are according to Viereck and Little (1972).
Metric Equivalents

1 inch (in) = 2.54 centimeters

1 foot (ft) = 0.3048 meter

1 mile (mi) = 1.609 kilometers

1 acre = 0.4047 hectare

1 cubic foot (ft3

) = 0.0283 cubic meter

1 cubic foot per acre (ft3 per acre) = 0.06997 cubic meter per hectare

Degrees Fahrenheit (°F) = 1.8 Celsius + 32

Literature Cited

Alerich, C.L.; Klevgard, L.; Liff, C.; Miles, P. 2004. The forest inventory and 

analysis database: database description and users guide version 1.7. http:// 

fhm-server.lv-hrc.nevada.edu/fia/imb/d-team/FIADB_v17_122104.pdf. 

(12 January 2005).

Nowacki, G.J.; Spencer, P.; Brock, T.; Fleming, M.; Jorgenson, T. 2001.

Unified ecoregions of Alaska and neighboring territories. [1:4,000,000]

Miscellaneous Investigations series I map. Open-file Report 02-297. 

Reston, VA: U.S. Department of the Interior, Geological Survey.

Scott, C.T.; Bechtold, W.A. 1995. Techniques and computations for mapping plot

clusters that straddle stand boundaries. Forest Science Monograph. 31: 46-61.

U.S. Department of Agriculture, Forest Service. 1998. Unpublished algorithms

for estimation of tree height and radial growth rates. On file with: U.S.

Department of Agriculture, Forest Service, Pacific Northwest Research Station,

3301 C St., Suite 200, Anchorage, AK 99503.

U.S. Department of Agriculture, Forest Service. 2000-2003. Field procedures 

for the south-central Alaska inventory. Anchorage, AK: Pacific Northwest

Research Station; Region 10 [Alaska Region]. Annual. 

Viereck, L.A.; Little, E.E., Jr. 1972. Alaska trees and shrubs. Agric. Handb. 410.

Washington, DC: U.S. Department of Agriculture. 265 p.

9

Timber Resource Statistics of South-Central Alaska, 2003
10

Resource Bulletin PNW-RB-248

Table 1—Estimated area by land class, owner group, and reserved component, south-central

Alaska, 2003a

Owner group Timberland Other forest land Total forest land Nonforest land All land

Thousand acres

National forest: 324 755 1,079 4,354 5,433

Reserved — (435) (435) (1,544) (1,978)

Other federal: 170 954 1,124 6,283 7,407

Reserved — (864) (864) (4,934) (5,798)

State and local 646 156 801 2,217 3,018

Private 736 305 1,040 1,582 2,622

All owners 1,875 2,169 4,044 14,435 18,480

— = no data were collected or less than 500 acres.

a Totals may be off owing to rounding. Estimates are subject to sampling error.

Table 2—Estimated area of forest land by owner group, reserved status, and forest type,

south-central Alaska, 2003a

Forest type National forest Other federal State and local Private All land

Thousand acres

Softwoods:

Black spruce—

Reserved — 312 — — 312

Unreserved 5 52 28 58 142

Total 5 364 28 58 455

Hemlock-spruce—

Reserved 126 6 — — 132

Unreserved — — 3 17 20

Total 126 6 3 17 152

Mixed conifer—

Reserved — 31 — — 31

Unreserved 146 1 69 70 287

Total 146 33 69 70 318

Mountain hemlock—

Reserved 303 49 — — 352

Unreserved 273 1 70 68 412

Total 576 50 70 68 764

Sitka spruce—

Reserved 6 15 — — 21

Unreserved 69 23 349 338 779

Total 74 39 349 338 800
11

Timber Resource Statistics of South-Central Alaska, 2003

Table 2—Estimated area of forest land by owner group, reserved status, and forest type,

south-central Alaska, 2003a (continued)

Forest type National forest Other federal State and local Private All land

Thousand acres

White spruce—

Reserved — 190 — — 190

Unreserved 28 42 107 126 303

Total 28 233 107 126 494

Western hemlock—

Reserved — — — — —

Unreserved 88 6 36 21 150

Total 88 6 36 21 150

Total softwoods:

Reserved 435 604 — — 1,039

Unreserved 608 126 661 698 2,094

Total 1,043 730 661 698 3,132

Hardwoods:

Aspen—

Reserved — 24 — — 24

Unreserved — 8 6 — 13

Total — 32 6 — 38

Paper birch—

Reserved — 172 — — 172

Unreserved 25 118 64 272 479

Total 25 290 64 272 651

Poplar—

Reserved — 64 — — 64

Unreserved 11 9 69 70 158

Total 11 72 69 70 222

Total hardwoods:

Reserved — 260 — — 260

Unreserved 36 134 139 342 651

Total 36 394 139 342 911

Mixed:

Spruce-birch—

Reserved — — — — —

Unreserved — — 1 — 1

Total — — 1 — 1

All types:

Reserved 435 864 — — 1,299

Unreserved 644 260 801 1,040 2,746

Total 1,079 1,124 801 1,040 4,044

— = no data were collected or less than 500 acres.

a Totals may be off owing to rounding. Estimates are subject to sampling error.
12

Resource Bulletin PNW-RB-248

Table 3—Estimated area of timberland by owner group and forest type, south-central Alaska,

2003a

Forest type National forest Other federal State and local Private All owners

Thousand acres

Softwoods:

Black spruce — 10 9 5 24

Mixed conifer 97 1 65 33 196

Mountain hemlock 49 — 35 21 105

Sitka spruce 56 18 307 314 695

Western hemlock 70 6 24 21 121

White spruce 28 37 88 107 260

Total softwoods 300 72 529 502 1,402

Hardwoods:

Aspen — 8 6 — 13

Paper birch 13 82 49 175 319

Poplar 11 9 63 58 141

Total hardwoods 24 98 117 234 474

All types 324 170 646 736 1,875

— = no data were collected or less than 500 acres.

a Totals may be off owing to rounding. Estimates are subject to sampling error.

Table 4—Estimated area of timberland by owner group and stand size class, south-central

Alaska, 2003a

Stand size class National forest Other federal State and local Private All owners

Thousand acres

Seedling and sapling 6 47 42 93 188

Poletimber 45 52 96 132 324

Young sawtimber 107 56 250 227 638

Old sawtimber 157 15 135 119 426

Nonstocked 10 — 123 165 298

All classes 324 170 646 736 1,875

— = no data were collected or less than 500 acres.

a Totals may be off owing to rounding. Estimates are subject to sampling error.
13

Timber Resource Statistics of South-Central Alaska, 2003

Table 5—Estimated area of timberland by owner group and cubic-foot site class, southcentral Alaska, 2003a

Site class National forest Other federal State and local Private All owners

Cubic feet -----------------------------------------Thousand acres-----------------------------------------

20-49 225 96 351 502 1,174

50-84 86 63 182 184 515

85-119 7 11 67 50 135

120-164 6 — 46 — 51

All classes 324 170 646 736 1,875

— = no data were collected or less than 500 acres.

a Totals may be off owing to rounding. Estimates are subject to sampling error.

Table 6—Estimated area of timberland by forest type and stand-size class, south-central Alaska, 2003a

Seedling Young Old All stand

Forest type and sapling Poletimber sawtimber sawtimber Nonstocked size classes

Thousand acres

Softwoods:

Black spruce 13 11 — — — 24

Mixed conifer 2 33 65 97 — 196

Mountain hemlock — 4 36 65 — 105

Sitka spruce 46 48 304 156 141 695

Western hemlock — — 21 100 — 121

White spruce 31 78 47 6 98 260

All softwoods 92 175 472 424 240 1,402

Hardwoods:

Aspen 1 10 — 2 — 13

Paper birch 71 111 89 — 49 319

Poplar 24 29 78 — 10 141

All hardwoods 97 150 166 2 59 474

All types 188 324 638 426 298 1,875

— = no data were collected or less than 500 acres.

a Totals may be off owing to rounding. Estimates are subject to sampling error.
14

Resource Bulletin PNW-RB-248

Table 7—Estimated number of growing-stock trees on timberland by species and diameter class, south-central Alaska, 2003a

Diameter class (inches at breast height)

5.0- 7.0- 9.0- 11.0- 13.0- 15.0- 17.0- 19.0- 21.0- All

Species 6.9 8.9 10.9 12.9 14.9 16.9 18.9 20.9 28.9 29.0+ classes

Thousand trees

Softwoods:

Black spruce 2,410 413 34 — — — — — 34 — 2,893Mountain hemlock 8,230 6,990 4,545 3,581 2,651 2,410 1,653 861 1,205 344 32,472Sitka spruce 28,861 23,611 14,920 12,505 8,682 8,037 5,032 3,871 8,813 2,932 117,264

Western hemlock 9,814 7,197 4,408 3,271 2,032 1,515 895 585 2,238 1,067 33,023White spruce 14,187 7,059 3,409 2,135 1,033 413 172 34 — — 28,443

Total 63,503 45,271 27,316 21,492 14,398 12,376 7,753 5,351 12,292 4,343 214,095

Hardwoods:

Black cottonwood 3,409 3,753 2,342 1,756 1,067 861 792 310 723 103 15,117Paper birch 4,614 3,306 3,065 1,997 792 551 310 69 34 — 14,738Quaking aspen 1,136 413 551 310 103 34 69 — 34 — 2,651

Total 9,160 7,472 5,957 4,063 1,963 1,446 1,171 379 792 103 32,507

All species 72,662 52,743 33,273 25,555 16,361 13,822 8,923 5,730 13,084 4,447 246,602— = no data were collected or less than 500 trees.

a Totals may be off owing to rounding. Estimates are subject to sampling error.
15

Timber Resource Statistics of South-Central Alaska, 2003

Table 8—Estimated net volume of growing stock and sawtimber on timberland by

class of timber, owner group, and species group, south-central Alaska, 2003a

Species group

Class of timber Average All

and owner group volume Softwoods Hardwoods species

Cubic feet

per acre --------------Million cubic feet--------------

Growing stock:b

National forest 3,657 1,142 43 1,185

Other federal 1,184 115 86 201

State and local 3,488 2,116 137 2,253

Private 1,969 1,309 140 1,449

Total growing stock 2,713 4,682 405 5,087

Board feet

per acre --------------Million board feet-------------

Sawtimber (Scribner rule):c

National forest 14,362 4,517 137 4,653

Other federal 3,436 391 192 583

State and local 14,341 8,846 416 9,262

Private 7,643 5,323 299 5,623

Total sawtimber 10,730 19,077 1,044 20,121

a Totals may be off owing to rounding. Estimates are subject to sampling error. b Includes growing-stock trees 5.0 in d.b.h. and larger.

c Includes softwood sawtimber trees 9.0 in d.b.h. and larger and hardwood sawtimber trees 

11.0 in d.b.h. and larger.
16

Resource Bulletin PNW-RB-248

Table 9—Estimated net volume of growing stock on timberland by species and diameter class, south-centralAlaska, 2003a

Diameter class (inches at breast height)

5.0- 7.0- 9.0- 11.0- 13.0- 15.0- 17.0- 19.0- 21.0- All

Species 6.9 8.9 10.9 12.9 14.9 16.9 18.9 20.9 28.9 29.0+ classes

Million cubic feet

Softwoods:

Black spruce 5 2 — — — — — — 6 — 13Mountain hemlock 19 35 43 57 64 78 74 45 99 51 564Sitka spruce 75 141 158 210 213 279 230 235 863 717 3,121

Western hemlock 25 41 52 59 49 51 40 37 231 224 809White spruce 32 34 31 33 24 11 7 2 — — 175

Total 156 253 284 359 350 419 351 319 1,199 992 4,682

Hardwoods:

Black cottonwood 4 15 19 25 22 28 35 15 62 19 246Paper birch 11 20 28 31 17 15 10 3 2 — 137Quaking aspen 2 2 6 5 2 1 2 — 2 — 22

Total 18 37 54 61 42 43 47 18 67 19 405

All species 174 290 337 420 392 462 398 337 1,266 1,012 5,087

— = no data were collected or less than 500,000 ft3.a Totals may be off owing to rounding. Estimates are subject to sampling error. Includes growing-stock trees 5.0 in d.b.h. and larger.
17

Timber Resource Statistics of South-Central Alaska, 2003

Table 11—Estimated net volume of growing stock on timberland by species 

and owner group, south-central Alaska, 2003a

National Other State All

Species forest federal and local Private owners

Million cubic feet

Softwoods:

Black spruce — 1 7 5 13

Mountain hemlock 282 2 195 84 564

Sitka spruce 427 32 1,665 998 3,121

Western hemlock 408 35 221 145 809

White spruce 25 45 27 77 175

Total 1,142 115 2,116 1,309 4,682

Hardwoods:

Black cottonwood 36 34 122 54 246

Paper birch 7 42 12 77 137

Quaking aspen — 10 3 9 22

Total 43 86 137 140 405

All species 1,185 201 2,253 1,449 5,087

— = no data were collected or less than 500,000 ft3. a Totals may be off owing to rounding. Estimates are subject to sampling error. Includes 

growing-stock trees 5.0 in d.b.h. and larger.

Table 10—Estimated net volume of sawtimber on timberland by species and diameter class, 

south-central Alaska, 2003a

Diameter class (inches at breast height)

9.0- 11.0- 13.0- 15.0- 17.0- 19.0- 21.0- All

Species 10.9 12.9 14.9 16.9 18.9 20.9 28.9 29.0+ classes

Million board feet, Scribner rule

Softwoods:

Black spruce — — — — — — 35 — 35

Mountain hemlock 117 181 238 297 302 191 453 204 1,982

Sitka spruce 452 717 810 1,159 1,013 1,094 4,282 3,838 13,365

Western hemlock 159 207 186 206 175 170 1,144 1,148 3,395

White spruce 68 89 75 35 26 8 — — 299

Total 797 1,193 1,309 1,697 1,516 1,462 5,914 5,190 19,077

Hardwoods:

Black cottonwood — 78 80 105 136 59 250 71 780

Paper birch — 77 49 41 32 11 10 — 221

Quaking aspen — 14 7 2 9 — 12 — 43

Total — 169 136 149 176 70 272 71 1,044

All species 797 1,362 1,445 1,846 1,692 1,532 6,185 5,261 20,121

— = no data were collected or less than 500,000 board feet.

a Totals may be off owing to rounding. Estimates are subject to sampling error. Includes softwood sawtimber trees 9.0 

in d.b.h. and larger and hardwood sawtimber trees 11.0 in d.b.h. and larger.
18

Resource Bulletin PNW-RB-248

Table 12—Estimated net volume of sawtimber on timberland by species and

owner group, south-central Alaska, 2003a

National Other State All

Species forest federal and local Private owners

Million board feet, Scribner rule

Softwoods:

Black spruce — — 35 — 35

Mountain hemlock 981 8 674 319 1,982

Sitka spruce 1,837 147 7,113 4,269 13,365

Western hemlock 1,656 169 980 591 3,395

White spruce 43 67 45 144 299

Total 4,517 391 8,846 5,323 19,077

Hardwoods:

Black cottonwood 133 100 396 151 780

Paper birch 3 65 18 134 221

Quaking aspen — 27 1 15 43

Total 137 192 416 299 1,044

All species 4,653 583 9,262 5,623 20,121

— = no data were collected or less than 500,000 board feet.

a Totals may be off owing to rounding. Estimates are subject to sampling error. Includes softwood sawtimber trees 9.0 in d.b.h. and larger and hardwood sawtimber trees 11.0 in d.b.h. and

larger.

Table 13—Estimated net volume of growing stock on timberland by forest type and stand-size

class, south-central Alaska, 2003a

Seedling - Young Old All

Forest type sapling Poletimber sawtimber sawtimber Nonstocked classes

Million cubic feet

Softwoods:

Black spruce 1 6 — — — 7

Mixed conifer 1 48 334 397 — 780

Mountain hemlock — 7 120 303 — 431

Sitka spruce 9 85 1,449 918 10 2,471

Western hemlock — — 111 716 — 827

White spruce 9 48 49 6 2 114

Total 19 194 2,063 2,340 12 4,629

Hardwoods:

Aspen — 6 — 1 — 7

Paper birch 6 80 123 — 2 212

Poplar 1 26 209 — 4 239

Total 7 111 332 1 6 458

All types 26 306 2,396 2,342 18 5,087

— = no data were collected or less than 500,000 ft3. a Totals may be off owing to rounding. Estimates are subject to sampling error. Includes growing-stock trees 5.0 in 

d.b.h. and larger.
19

Timber Resource Statistics of South-Central Alaska, 2003

Table 14—Estimated net volume of sawtimber on timberland by forest type and stand-size class,

south-central Alaska, 2003a

Seedling - Young Old All

Forest type sapling Poletimber sawtimber sawtimber Nonstocked classes

Million board feet, Scribner rule

Softwoods:

Black spruce — 5 — — — 5

Mixed conifer 1 81 1,434 1,539 — 3,054

Mountain hemlock — 6 367 1,182 — 1,555

Sitka spruce 7 111 5,971 4,410 21 10,519

Western hemlock — — 383 3,249 — 3,632

White spruce 3 49 102 13 — 168

Total 11 252 8,257 10,392 21 18,933

Hardwoods:

Aspen — 4 — 4 — 7

Paper birch 6 81 307 — 1 395

Poplar — 51 720 — 15 785

Total 6 135 1,027 4 16 1,188

All types 17 387 9,284 10,396 37 20,121

— = no data were collected or less than 500,000 board feet.

a Totals may be off owing to rounding. Estimates are subject to sampling error. Includes softwood sawtimber trees 9.0 in

d.b.h. and larger and hardwood sawtimber trees 11.0 in d.b.h. and larger.

Table 15—Estimated net volume of growing stock on timberland by forest 

type and owner group, south-central Alaska, 2003a

National Other State All

Forest type forest federal and local Private owners

Million cubic feet

Softwoods:

Black spruce — — 2 4 7

Mixed conifer 369 5 305 101 780

Mountain hemlock 178 — 172 80 431

Sitka spruce 179 21 1,365 906 2,471

Western hemlock 408 42 229 148 827

White spruce 20 24 23 47 114

Total 1,154 92 2,096 1,287 4,629

Hardwoods:

Aspen — 3 4 — 7

Paper birch 7 72 20 112 212

Poplar 24 34 131 50 239

Total 31 108 156 162 458

All types 1,185 201 2,253 1,449 5,087

— = no data were collected or less than 500,000 ft3. a Totals may be off owing to rounding. Estimates are subject to sampling error. Includes grow- ing-stock trees 5.0 in d.b.h. and larger.
20

Resource Bulletin PNW-RB-248

Table 16—Estimated net volume of sawtimber on timberland by forest

type and owner group, south-central Alaska, 2003a

National Other State All

Forest type forest federal and local Private owners

Million board feet, Scribner rule

Softwoods:

Black spruce — — 2 3 5

Mixed conifer 1,410 20 1,292 333 3,054

Mountain hemlock 619 — 611 325 1,555

Sitka spruce 775 86 5,785 3,874 10,519

Western hemlock 1,724 218 1,032 658 3,632

White spruce 29 18 35 86 168

Total 4,557 342 8,756 5,279 18,933

Hardwoods:

Aspen — 4 4 — 7

Paper birch 3 137 49 206 395

Poplar 94 101 453 138 785

Total 97 241 506 344 1,188

All types 4,653 583 9,262 5,623 20,121

— = no data were collected or less than 500,000 board feet.

a Totals may be off owing to rounding. Estimates are subject to sampling error. Includes softwood sawtimber trees 9.0 in d.b.h. and larger and hardwood sawtimber trees 11.0 in d.b.h. and

larger.

Table 17—Estimated current average gross annual growth of growing

stock on timberland by owner group and species group, south-central

Alaska, 2003a

Species group

Average All

Owner group volume Softwoods Hardwoods species

Cubic feet

per acre -------------Thousand cubic feet------------

Growing stock:b

National forest 39 12,044 744 12,788

Other federal 24 2,344 1,750 4,094

State and local 40 23,221 2,565 25,785

Private 29 17,782 3,223 21,006

Total growing stock 34 55,392 8,282 63,673

a Totals may be off owing to rounding. Estimates are subject to sampling error. b Includes growing-stock trees 5.0 in d.b.h. and larger.
21

Timber Resource Statistics of South-Central Alaska, 2003

Table 19—Estimated current average net annual growth of sawtimber on

timberland by forest type and owner group, south-central Alaska, 2003a

National Other State All

Forest type forest federal and local Private owners

Thousand board feet, Scribner rule

Softwoods:

Black spruce — — 66 110 176

Mixed conifer 4,631 221 3,703 3,677 12,232

Mountain hemlock -11,248 — -3,774 2,852 -12,171

Sitka spruce 7,217 1,575 -15,155 31,449 25,085

Western hemlock 10,486 985 2,607 2,295 16,373

White spruce -1,082 -2,893 -16,117 -30,881 -50,974

Total 10,003 -112 -28,671 9,501 -9,279

Hardwoods:

Aspen — 143 152 — 295

Paper birch 53 282 -13,198 -5,797 -18,659

Poplar 2,630 2,316 3,252 5,963 14,162

Total 2,684 2,741 -9,793 167 -4,202

All types 12,686 2,629 -38,464 9,668 -13,481

— = no data were collected or less than 500 board feet. a Totals may be off owing to rounding. Estimates are subject to sampling error. Includes soft

wood sawtimber trees 9.0 in d.b.h. and larger and hardwood sawtimber trees 11.0 in d.b.h. and

larger.

Table 18—Estimated current average net annual growth of growing stock on 

timberland by forest type and owner group, south-central Alaska, 2003a

National Other State All

Forest type forest federal and local Private owners

Thousand cubic feet

Softwoods:

Black spruce — 9 110 96 215

Mixed conifer 1,817 62 1,130 1,314 4,324

Mountain hemlock -2,136 — -1,032 748 -2,420

Sitka spruce 1,723 318 -4,966 6,537 3,611

Western hemlock 3,070 258 541 418 4,287

White spruce 35 -808 -6,681 -10,349 -17,803

Total 4,508 -160 -10,897 -1,237 -7,786

Hardwoods:

Aspen — 141 141 — 281

Paper birch 228 734 -4,400 -1,198 -4,636

Poplar 415 541 886 1,530 3,373

Total 643 1,416 -3,373 332 -982

All types 5,152 1,256 -14,270 -904 -8,767

— = no data were collected or less than 500 ft3. a Totals may be off owing to rounding. Estimates are subject to sampling error. Includes 

growing stock trees 5.0 in d.b.h. and larger.
22

Resource Bulletin PNW-RB-248

Table 20—Estimated average annual mortality of growing stock on timberland by forest type and owner group, south-central Alaska, 2003a

National Other State All

Forest type forest federal and local Private owners

Thousand cubic feet

Softwoods:

Black spruce — — 75 33 108

Mixed conifer 2,453 — 1,814 283 4,551

Mountain hemlock 3,856 — 2,699 — 6,555

Sitka spruce 406 — 20,839 5,056 26,301

Western hemlock 243 — 848 618 1,709

White spruce 666 1,679 7,602 11,967 21,914

Total 7,623 1,679 33,877 17,957 61,136

Hardwoods:

Aspen — — 13 — 13

Paper birch 13 1,159 4,821 3,952 9,946

Poplar — — 1,344 1 1,345

Total 13 1,159 6,178 3,953 11,304

All types 7,636 2,838 40,055 21,910 72,441

— = no data were collected or less than 500 ft3. a Totals may be off owing to rounding. Estimates are subject to sampling error. Includes growing-stock trees 5.0 in d.b.h. and larger.

Table 21—Estimated average annual mortality of sawtimber on timberland

by forest type and owner group, south-central Alaska, 2003a

National Other State All

Forest type forest federal and local Private owners

Thousand board feet, Scribner rule

Softwoods:

Black spruce — — — — —

Mixed conifer 9,561 — 6,139 658 16,357

Mountain hemlock 16,529 — 8,731 — 25,260

Sitka spruce 1,019 — 69,907 16,290 87,217

Western hemlock 91 — 2,569 1,170 3,830

White spruce 1,873 3,383 16,928 32,459 54,643

Total 29,073 3,383 104,274 50,577 187,308

Hardwoods:

Aspen — — — — —

Paper birch — 2,159 13,802 9,696 25,657

Poplar — — 5,062 — 5,062

Total — 2,159 18,863 9,696 30,719

All types 29,073 5,543 123,137 60,274 218,026

— = no data were collected or less than 500 board feet.

a Totals may be off owing to rounding. Estimates are subject to sampling error. Includes softwood sawtimber trees 9.0 in d.b.h. and larger and hardwood sawtimber trees 11.0 in d.b.h. and

larger.
23

Timber Resource Statistics of South-Central Alaska, 2003

Table 22—Estimated timber harvest volume

(scaled postharvest) by year and owner group,

south-central Alaska, 1988 to 2001a

National All

Year forest State Private owners

Million board feet, Scribner rule

1988 1.0 2.1 85.6 88.7

1989 1.5 2.1 120.0 123.6

1990 1.5 1.0 105.1 107.6

1991 1.5 2.5 134.5 138.5

1992 .5 1.0 123.5 125.0

1993 1.7 .0 127.2 128.9

1994 6.5 .0 186.0 192.5

1995 1.9 2.6 230.1 234.6

1996 3.3 8.1 207.6 219.0

1997 2.2 8.6 237.1 247.9

1998 1.5 5.0 172.2 178.7

1999 .4 5.4 139.9 145.7

2000 .3 1.8 56.3 58.4

2001 .4 2.1 71.3 73.8

a Source: USDA Forest Service, Alaska Region. Data on

file with: Ecosystems Planning, USDA Forest Service, 

P.O. Box 21628, Juneau, AK 99802-1628.

Table 23—Standard errors of selected inventory estimates,

south-central Alaska, 2003

Attribute Estimate Standard error

Percent

All forest land 4,044 thousand acres 3.4 

Other forest land 2,169 thousand acres 5.1

Timberland 1,875 thousand acres 5.0

Nonforest land 14,435 thousand acres .9

Net volume 5,087 million cubic feet 8.4

Gross growth 63,671 thousand cubic feet 6.4

Mortality 72,438 thousand cubic feet 16.1
24

Resource Bulletin PNW-RB-248

Table 24—Approximate confidence intervals for timberland area and growing-stock 

volume estimates of varying magnitudes, south-central Alaska, 2003

Timberland area Growing-stock volume

Estimate Confidence interval Estimate Confidence interval

------Thousand acres------ Percent ------Million cubic feet------ Percent

2,000 ±98 5 6,000 ±467 8

1,500 ±84 6 4,000 ±381 10

1,000 ±69 7 2,000 ±270 13

800 ±62 8 1,000 ±191 19

600 ±53 9 800 ±170 21

400 ±44 11 600 ±148 25

200 ±31 15 400 ±121 30

100 ±22 22 200 ±85 43

50 ±15 31 100 ±60 60

25 ±11 44 50 ±43 85

15 ±8 56

10 ±7 69

5 ±5 98
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