Projecting Other Public Inventories for the 

2005 RPA Timber Assessment Update

Projecting Other Public Inventories for the 

2005 RPA Timber Assessment Update

Xiaoping Zhou, John R. Mills, and Richard W. Haynes

U.S. Department of Agriculture Forest Service

A Technical Document Supporting 

the USDA Forest Service Interim Update of the 2000 RPA Assessment

A Technical Document Supporting 

the USDA Forest Service Interim Update of the 2000 RPA Assessment
Authors

Xiaoping Zhou is a forester, John R. Mills and Richard W. Haynes are research

foresters, Forestry Sciences Laboratory, P.O. Box 3890, Portland, OR 97208.
Abstract

Zhou, Xiaoping; Mills, John R.; Haynes, Richard W. 2007. Projecting other

public inventories for the 2005 RPA timber assessment update. Gen. Tech. Rep.

PNW-GTR-717. Portland, OR: U.S. Department of Agriculture, Forest

Service, Pacific Northwest Research Station. 31 p.

This study gives an overview of the current inventory status and the projection of

future forest inventories on other public timberland. Other public lands are lands

administered by state, local, and federal government but excluding National Forest

System lands. These projections were used as part of the 2005 USDA Forest Service

Resource Planning Act timber assessment update. The projections were made by

region and forest type by using the modified Aggregated Timberland Assessment

System and the forest inventory data with methods and procedures consistent with

the methods used for private and national forest inventory projections. Although the

projected inventory volume differs by region, both softwood and hardwood inventories on other public timberlands in the United States are projected to increase over

60 percent during the next 50 years. Forest net growth exceeds harvest in most

regions pushing inventory volumes up. The one exception is the Pacific Northwest

East (ponderosa pine region) where the softwood inventory is expected to decrease

until 2030 owing to lower softwood net growth and then slowly increase. The

mature and old mature stands for both softwood and hardwood are projected to

increase significantly for all regions especially in the South region where proportion

of mature and old mature increases from 9 to 54 percent for softwood and 4 to 55

percent for hardwood.

Keywords: Other public timberlands, timber supply, modeling, inventory

projection, yield function, forest structure, public policy, seral stage.
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Projecting Other Public Inventories for the 2005 RPA Timber Assessment Update

Introduction

The past two decades have seen significant efforts in developing consistent ways of

describing and projecting timber inventories by region and owner. Among other

purposes, these projections are used in the timber assessments required by the Forest and Rangeland Renewable Resource Planning Act (RPA) of 1974. Summaries

for harvest, growth, and inventories are key parts of an RPA timber assessment (see

tables 16 and 17 in Haynes 2003). These summary tables and their predecessors

have shaped public perceptions of both the magnitudes and trends in total U.S.

forest inventories and resource conditions. They also illustrate the relative contributions of different owners and regions. The states making up the various regions are

shown in table 1. The traditionally recognized ownerships for forest resource

information include national forest, other public, forest industry, and nonindustrial

private forest owners. Here we focus on the other public ownership, which includes

the U.S. Department of the Interior’s National Park Service, Bureau of Land Management, and Fish and Wildlife Service; U.S. Department of Defense and U.S.

Department of Energy; other federal, state, and local (county, municipal, etc.), and

nonfederal public.

One of the goals of the assessment process has been to develop consistent

inventory projection approaches for all timberland owners across all regions so that

all resource conditions (regardless of owner) could be summarized comparably.

This started following the 1980 assessment (USDA FS 1982), when efforts focused

on increasing the amount of detail represented in the forest inventory projection

models. The first step was the implementation of the Aggregate Timberland Assessment System (ATLAS; Mills and Kincaid 1992) for private timberland owners in

the 1990 RPA timber assessment (Haynes 1990). At that time, the ability to produce detailed projections for public owners was limited because the inventory

system used by U.S. Department of Agriculture, Forest Service Forest Inventory

and Analysis (FIA) was not applied to national forest lands in the West. During the

1990s, the scope of FIA data broadened to include consistent data for all ownerships. The 2000 RPA timber assessment (Haynes 2003) included the implementation of expanded forest management intensities on private lands and the first

detailed set of inventory projections made for the national forest lands. Here we

describe the completion of this process with the inclusion of the other public

ownership into the inventory projection system. This ownership has about 10 percent of the timberland in the United States, that is, about 50.3 million acres (table

2) including Alaska. These projections were developed for the 2005 RPA timber

One of the goals of

the assessment

process has been to

develop consistent

inventory projection

approaches for all

timberland owners

across all regions

so that all resource

conditions (regardless of owner) could

be summarized

comparably.
2

GENERAL TECHNICAL REPORT PNW-GTR-717

Table 1—Other public forest Forest and Rangeland Renewable Resource Planning

Act (RPA) regions

RPA

region Region name States

0 Pacific Northwest West Western Oregon, western Washington

1 Pacific Northwest East Eastern Oregon, eastern Washington

2 Pacific Southwest California

3 Rocky Mountain North Idaho, Montana

4 Rocky Mountain South Arizona, Colorado, Nevada, New Mexico,

South Dakota, Utah, Wyoming

5 North Central, Plains States Illinois, Indiana, Iowa, Kansas, Missouri,

Nebraska, Ohio

6 North Central, Lake States Michigan, Minnesota, Wisconsin,

North Dakota

7 Northeast Connecticut, Delaware, Maine, Maryland,

Massachusetts, New Hampshire, New Jersey,

New York, Pennsylvania, Rhode Island,

Vermont, West Virginia

8 South Central Alabama, Arkansas, Kentucky, Louisiana,

Mississippi, Oklahoma, Tennessee, Texas

9 Southeast Florida, Georgia, North Carolina, South

Carolina, Virginia

10 Alaska Alaska (not projected with the model)

Table 2—Status of other public forest land by region

Region Total forest land Timberland Other forest land

Thousand acres

Pacific Northwest West 6,283 4,594 1,689

Pacific Northwest East 2,340 1,000 1,340

Pacific Southwest 4,964 383 4,581

Rocky Mountain North 4,753 3,152 1,601

Rocky Mountain South 27,616 2,964 24,652

Plains States 2,847 1,960 887

Lake States 14,623 13,020 1,603

Northeast 12,754 7,921 4,833

South Central 6,060 5,082 978

Southeast 7,340 4,899 2,441

Alaska 80,539 5,321 75,218

Total area 170,119 50,296 119,823
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Projecting Other Public Inventories for the 2005 RPA Timber Assessment Update

assessment update (Haynes and others 2007), and will provide, for the first time

since the 1980 assessment, a consistent inventory projection across all ownerships.

For the past two decades, inventory projections for other public ownerships

were made by using a growth-drain identity1

 and assumed harvest and growth levels

extrapolated from historical trends. The latest projections using the growth-drain

identity were done for the 2000 RPA timber assessment and are shown in figure 1.

These projections suggest that softwood and hardwood inventories would follow

similar trajectories and increase in the future. In terms of the total contribution to

the national inventory, the other public ownership averages about 17 percent of the

U.S. inventory volume over the 100-year period. Changing definitions and inventory designs of the other public ownership, especially the 1991 transfer of American Indian or tribal timberlands from the other public to the nonindustrial private

ownership group, complicates making general observations about past trends in

resource conditions.

The purpose of this paper is twofold. First, we describe the input information

and assumptions necessary to use the same techniques and assumptions for the

other public ownership as were used for other ownership groups. This involves the

modification of the ATLAS inventory projection system and structuring the data

sets in management units around timber types and described by age class. Second,

we present a set of inventory projections for the other public ownership for use in

national inventory summaries, and we discuss the contributions of the other public

landowners to broad-scale concerns associated with forest structure.

Current Status of Other Public Timberland

The most recent periodic inventory data for each state were assembled from the

2002 RPA database (Smith and others 2004), and it is used as a starting point of

the inventory projections. There are 749 million acres of forest land in the United

States, of which about 20 percent is included in national forests, 23 percent is in

other public ownership, and the remainder is privately owned. A subset of 504

million acres is considered timberland. By definition, timberland is forest land that

is capable of producing at least 20 cubic feet per acre per year of industrial wood in

natural stands, and not withdrawn from timber utilization or administrative regulation. Across the four ownership categories there are large differences in the proportion of forest land that is classified as timberland. For example, 83 percent of all

1 The growth-drain identity is expressed as I

t

 = It-1 + G – H where I

t

 is inventory in period

t, G is the periodic net growth, and H is the periodic removals between periods t and t-1.

In terms of the total

contribution to the

national inventory,

the other public

ownership averages

about 17 percent of

the U.S. inventory

volume over the

100-year period.
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GENERAL TECHNICAL REPORT PNW-GTR-717

privately owned forest land is timberland, 65 percent of the national forests forest

land is timberland, but only 30 percent of the other public forest land is timberland (50 percent if excluding Alaska). This implies that on average, forest lands

in other public ownership are less productive than forest lands in the other ownerships. This also reflects that other public ownership has a greater portion of forest

land in the reserved category than any other ownership. In fact, the forest lands

owned by National Park Service and Departments of Defense and Energy are

almost all reserved. Other public timberland distribution differs across regions.2

The current areas of other public forest land by region based on the 2002 RPA

database are shown in table 2. For the 48 continental states, most of the other

public forest land is located in the Rocky Mountain, North Central (Plains States

plus the Lake States), and Northeast regions. Although the Rocky Mountain South

region has the largest number of forest-land acres outside of Alaska, only 11 percent is timberland. A similar situation exists for the Pacific Southwest and the

2 The RPA timber assessment divides the 48 continental states into 10 assessment regions.

Figure 1—Other public inventory projected by using the growth-drain formulation. (Source: Haynes

2003).
5

Projecting Other Public Inventories for the 2005 RPA Timber Assessment Update

Pacific Northwest East regions, where less than half of the forest land is classified

as timberland. Alaska, with about 7 percent of forest land in timberland, is unique,

but Alaska and Hawaii are not included in the ATLAS projections.

Figure 2 also helps to reveal a difference in public timberland land ownership

patterns between the Eastern and Western United States. The map in figure 2 was

derived from FIA plot data and shows the approximate plot locations where other

public timberland was encountered (based on fuzzed and swapped plot coordinates3

). It shows that the other public ownership is more broadly distributed in the

East where it is often in relatively small parcels interspaced among other timberland owners. Figure 2 also illustrates that there are relatively few places with large

blocks of contiguous other public timberlands. National forests are typically in

larger parcels, and most of the publicly owned timberland in the East is in other

public ownership, whereas most of the publicly owned timberland in the West is in

national forests. The following tabulation (in millions of acres, not including

Alaska) shows that Western national forests dominate the public timberland arena:

National Other

Area forests public

East 21.1 32.9

West 71.1 12.1

Figure 3 shows the initial distribution of other public timberland area by stand

age and broad region based on the 2002 RPA database. The North has about 50

percent of the other public timberland, and consequently those forests dominate the

appearance of the forest inventory structure. Inventories in the South are significantly younger than those in the North and West. Ninety-five percent of other

public timberland in the South is less than 50 years old, whereas this is true for

only 38 percent of the northern and 32 percent of the western timberland. Within

the North, 86 percent of stands are less than 100 years old and about 9 percent are

older than 150 years; whereas in the West, about 76 percent of other public timberland is less than 100 years old and 9 percent is equal to or older than 150 years.

Compared with other regions, the West shows a more uniform age distribution.

3 By law, any data tied to an individual landowner in nonpublic land cannot be disclosed.

So the plot location in the database is moved (plus/minus) up to a mile (fuzzed), and up to

5 percent of private plots may have their locations switched with similar plots (swapped).

Most of the publicly

owned timberland in

the East is in other

public ownership,

whereas most of

the publicly owned

timberland in the

West is in national

forests.
6

GENERAL TECHNICAL REPORT PNW-GTR-717

Figure 2—Other public timberland distribution.

Figure 3—Initial distributions (2002) of other public timberland area by region and age. Note: The bump of

areas at age class 175 represents an aggregation of all stands in the North of 175 and older.
7

Projecting Other Public Inventories for the 2005 RPA Timber Assessment Update

Projection Model and Assumptions

The inventory projections for other public ownerships are modeled by using the

same methods as those used for the private (both forest industry and nonindustrial

private forests) and national forest ownerships. This involves using an updated

version of ATLAS (Mills and Kincaid 1992). The inventory was structured in

ATLAS much the same way it was structured to project national forest inventories

(Mills and Zhou 2003). Basic assumptions involve the inventory stratification, the

development of yield functions for each forest type and region, assumptions about

mortality, the development of management intensity classes, the assumption concerning harvest levels and harvest methods, as well as any area change assumptions.

The following section will provide some detail regarding these assumptions.

Age classes—

Timberland in the East was stratified into 18 age classes. Because the western public

lands generally support some of the oldest forests, the West was stratified into 26

age classes in an effort to better identify potential late-seral-stage conditions. A

10-year stand age interval for age class was used for all regions except the South

where the inventory was aggregated into 5-year classes. In the periodic FIA inventory, stand age is the average total age, to the nearest year, of the trees in the

predominant stand-size class of the condition (determined using local procedures).

The various seral stage4

 definitions are the same here as used in other RPA applications (Haynes 2003). The intent of using these classes is to help quantify forest

development and to provide a sense of forest structure.

Yield functions—

Yield tables for other public timberland were developed for each forest type in a

region by using the FIA plot and tree information. These procedures were also

applied to national forest (Mills and Zhou 2003). Each plot record contains empirical growth rates that embody the effects of historical and recent management

4

 Seral stage—A stage or recognizable condition of a plant community that occurs during

its development from bare ground to climax. Used here, forests are assumed to progress

through five recognized stages: seedlings (age 5 all regions and fiber except North

softwood, which includes 5 to 15); poles and saplings (age 25 to 35 North softwood; 15 to

35 North hardwood; 10 to 15 South softwood; 10 to 20 South hardwood; 15 to 35 West

hardwood and softwood); young (age 45 to 65 North; 20 to 35 South softwood; 25 to 55

South hardwood; 45 to 75 West softwood; 45 to 55 West hardwood); mature (age 75 to

135 North; 40 to 75 South softwood; 60 to 75 South hardwood; 85 to 135 West softwood;

65 to 135 West hardwood); and old mature (age 145+ North; 80+ South; 145+ West).

These stages are represented by grouping age classes. The age-class groupings differ by

broad regions reflecting successional differences among various timber types.
8

GENERAL TECHNICAL REPORT PNW-GTR-717

practices. The simple statistical regression against the age class was used to estimate

the net annual growth, and the yields were then an accumulation of net annual

growth. The following tabulation represents the approach to develop a yield table

for a 10-year-interval age classification:

Age class Net growth Yield

0 G0 Y0

 = 0

1 G1 Y1

 = (G0 + G1)/2 x 5

2 G2 Y2

 = (G1 + G2)/2 x 10+ Y1

3 G3 Y3 = (G2 + G3)/2 x 10+ Y2

4 G4 Y4 = (G3 + G4)/2 x 10+ Y3

...... ...

Where Gac = net growth (ft3

•yr-1•acre-1) at age class ac.

Yac = yield at age class ac.

The variable Yac represents the net growing-stock volume (ft3

/acre) at the age

class midpoint (e.g., for ac = 0, age = 5; for ac = 1, age = 15; and when ac = 2,

age = 25, etc.). The general model of the net growth (G) as a function of age class

(ac) is expressed as G = f(ac). This can be illustrated for the Douglas-fir forest type

on other public timberland in the Pacific Northwest West region (for age classes

greater than zero (ac>0)) as:

Gac = 506.8 - 33.06ac + 0.96 ac2

 – 143.96e(1/ac) (ac>0) (1)

Values from the solution of equation (1) for the first eight age classes for

Douglas-fir are shown in the following tabulation:

Age range Age class Growth age class

Years Cubic feet per acre

0 to 10 0

10 to 20 1 83.4

21 to 30 2 207.2

31 to 40 3 215.3

41 to 50 4 205.1

51 to 60 5 189.7

61 to 70 6 172.9

71 to 80 7 156.4

...... ...
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Projecting Other Public Inventories for the 2005 RPA Timber Assessment Update

In regions with very few observations from other public timberlands, yields

were constructed by adding FIA plots from private lands. In the South, the yield

functions for national forest were used for other public timberlands assuming that

forests in both ownerships would have similar yield trajectories. For the Pacific

Northwest West, because of their small proportion, pines were grouped with the fir

and spruce timber type. The complete set of yield tables developed for each region

can be found in appendix tables 6 to 14.

There is a critical assumption in the use of these empirical yield functions;

assuming the future conditions will be similar to those in the recent past. If future

conditions differ significantly from those in the past, then this approach is subject

to bias. For example, management practices, atmospheric pollution, climate

change, and use of improved genotypes can influence future growth compounding

errors associated with using empirical data to project stands forward (Adlard 1995).

Mortality—

As canopy closure occurs in a stand with differential tree growth, the slower growing trees become suppressed leaving them less resistant to the effects of weather

(drought and wind), insects, and disease (Oliver and Larson 1990). So as forest

stands age and average tree diameter increases, the number of living trees in the

stand typically decreases owing to mortality of trees unable to compete for the

limited resources (Davis and Johnson 1987). Oliver and Larson (1990) identified

two categories of mortality, regular mortality and irregular mortality. On a landscape scale, regular mortality is part of forest succession, occurring as trees age

and compete with each other for light and water. Meanwhile, irregular mortality is

associated with disturbances such as fire, insect epidemics, or disease that kill what

are otherwise healthy trees. Mortality is measured by successive surveys and counted

as the volume in the trees that have died over a fixed interval.

The starting forest inventory data were compiled by FIA to represent net values

for all volumes (growth, inventory, removals), and consequently the projections

represent net values as well. Net values consider only live trees. Net annual growth

is the average annual net increase in the volume of trees during the period between

inventories (Smith and others 2004). Using net values to calibrate the growth

models is an implicit approach to considering mortality. For example, the growthand-yield relationships were developed from a cross section of field plots, many of

which represent stands that would be expected to have past histories with various

levels of mortality. For a handful of plots, net growth was reported to be a negative

value, meaning the volume of mortality exceeded the gross increment from growth.
10

GENERAL TECHNICAL REPORT PNW-GTR-717

This likely indicates a recent disturbance to the stand. These plots were included in

the process to calibrate net inventory growth, so this background level of mortality

is part of the projection. On a landscape level, we assert these projections reflect

the average rate of historical mortality.

Management intensity—

Other public timberland projections allow three management regimes that differ by

the approach to harvest. The first allows regeneration harvest, that is, a final harvest

or clearcut will occur in these stands at a range of ages typically followed by the

planting of seedlings. The second regime was developed to apply a partial harvest—

this treatment removes a portion of volume to mimic a stand subject to multiple

entries. The third management option is labeled no-harvest, as these stands are

projected forward in time but not subjected to harvesting. Acres are enrolled into

these management intensities upon regeneration; and the amount moving into any

one regime depends on the acres of final harvest and the enrollment rates set for

that regime. Harvest is set to occur at younger ages in the South than in the West,

reflecting the rate stands mature into various product classes. The number of acres

treated for harvest in a regime depends on the harvest request and relative available

volume within the regime.

Area change—

The area of other public timberland is assumed to remain unchanged for the next 50

years. The model is flexible for implementing area and forest type changes, but for

public lands these transitions are occurring more slowly than on private lands where

urbanization, agriculture, changing land ownership, and management objectives

play a dynamic role in shaping timberlands.

Site class—

Other public timberland covers a range of site productivity from 20 to more than

225 cubic feet of net growth per acre per year as measured at the culmination of

mean annual increment. Most other public timberland in the Pacific Northwest

West produces, for example, over 120 cubic feet per acre per year, whereas other

regions generally produce less. Because there were insufficient data to tailor the

other public management regimes for different site classes, yield functions representing an average site class were used in making projections.

Harvest projections—

Harvest for the other public owners is assumed to be set by various agency policies.

In 1997, removals from other public ownerships were 948 million cubic feet. We
11

Projecting Other Public Inventories for the 2005 RPA Timber Assessment Update

extrapolated projections of future harvest for this owner from past trends. These

projected harvests generally increase reflecting the observed propensity of many

agencies to increase harvest as inventory and net growth increases. This tendency

follows sustained yield management practices. Given the diversity of land management agencies, other assumptions would be difficult to develop. Several of the state

land management agencies are obligated to manage for high returns to support

school common (trust) funds.

Other parameters—

Several other parameters are required for an ATLAS projection. These contribute to

the calibration of growth, the assignment of stocking upon regeneration, the proportion of hardwood and softwood fiber in the inventory, and the descriptive variables

such as average diameter by age. These empirical values are derived from variables

from the FIA plot and tree data (see Mills 1990, Mills and Kincaid 1992 for their

relevance).

Assumptions for forest land excluded from harvest—

Although presented in the area summary tables (table 2), projections include only

timberland. That is, they do not include forest land officially reserved (wilderness

areas, national parks, etc.) or lands classified as nonproductive forest land. Across

the broader landscape, these latter areas are important contributors to ecosystem

diversity, provide wildlife habitat, sequester carbon dioxide from the atmosphere,

and provide other ecosystem services, such as clean water and recreational opportunities. Data are not yet available to project these forests but may become available

in the future as the need for various broad-scale studies evolves.

Projection Results

The removals from other public timberland are projected to increase for both softwoods and hardwoods for the next five decades as shown in tables 3 and 4. Softwood removals are projected to increase by 25 percent from 553 million to 691

million cubic feet by 2050, whereas hardwood removals will increase by 20 percent from 381 million to 456 million cubic feet. The relative change in the projected level of removals is expected to differ significantly by region, however.

Softwood removals decline in the Northeast, Pacific Southwest, and Pacific Northwest East by 29, 52, and 45 percent, respectively. Whereas the North Central is

relatively stable, large increases occur in the Southeast (14 percent), South Central

(24 percent), Rocky Mountains (184 percent), and Pacific Northwest West (39

percent). Alaska was not projected with ATLAS but rather a growth-drain table was

The removals from

other public timberland are projected

to increase for both

softwoods and hardwoods for the next

five decades.
12

GENERAL TECHNICAL REPORT PNW-GTR-717

Table 3—Softwood inventory, annual removals, and net annual growth projected for

other public timberland

Projections

Region 1997 2002 2010 2020 2030 2040 2050

Million cubic feet

Northeast:

 Removals 13 14 12 12 11 10 10

 Inventory 2,797 3,111 3,414 3,798 4,185 4,564 4,923

 Net annual growth 61 63 47 50 49 47 45

North Central:

 Removals 71 59 59 57 57 56 56

 Inventory 5,272 5,275 6,320 7,415 8,488 9,560 10,586

 Net annual growth 141 141 164 165 164 161 158

Southeast:

 Removals 114 112 101 108 115 123 128

 Inventory 4,452 4,577 5,677 6,154 6,217 6,291 6,385

 Net annual growth 145 155 174 124 127 137 138

South Central:

 Removals 61 63 60 67 70 75 78

 Inventory 1,951 2,179 2,210 2,431 2,517 2,550 2,579

 Net annual growth 66 81 92 81 78 80 83

Rocky Mountains:

 Removals 49 51 92 112 125 139 145

 Inventory 8,427 8,503 9,777 10,661 11,208 11,503 11,646

 Net annual growth 168 169 211 190 174 164 157

Pacific Southwest:a

 Removals 23 23 9 11 11 11 11

 Inventory 1,320 1,320 1,412 1,517 1,622 1,719 1,811

 Net annual growth 29 29 20 22 21 21 20

Pacific Northwest West:b

 Removals 159 159 210 222 222 221 221

 Inventory 19,243 19,243 22,495 25,835 29,172 32,505 35,766

 Net annual growth 491 459 545 556 550 551 542

Pacific Northwest East: b

 Removals 67 67 49 48 44 40 37

 Inventory 2,537 2,539 2,458 2,401 2,371 2,392 2,449

 Net annual growth 67 27 42 42 42 42 43
13

Projecting Other Public Inventories for the 2005 RPA Timber Assessment Update

Table 3—Softwood inventory, annual removals, and net annual growth projected for

other public timberland (continued)

Projections

Region 1997 2002 2010 2020 2030 2040 2050

Million cubic feet

Alaska:

 Removals 5 5 5 5 5 5 5

 Inventory 5,090 5,090 5,637 6,129 6,621 7,112 7,604

 Net annual growth 40 54 54 54 54 54 54

United States:

 Removals 562 553 597 642 660 680 691

 Inventory 51,089 51,837 59,400 66,341 72,401 78,196 83,749

 Net annual growth 1,208 1,178 1,349 1,284 1,259 1,257 1,240

Note: In 1991, Native American lands were transferred to nonindustrial private forest; previously

they were in other public.

Note: Historical harvest data are estimates of harvest trends and differ somewhat from the estimates

of actual consumption shown in some tables. For the projection years, the data show the average

volume that would be harvested given the assumptions of the study.

a

 Pacific Southwest excludes Hawaii.

b

 Pacific Northwest West (western Oregon and western Washington) is also called the Douglas-fir

subregion, and Pacific Northwest East (eastern Oregon and eastern Washington) is also called the

ponderosa pine subregion.

Source: Haynes and others 2007.

Table 4—Hardwood inventory, annual removals, and net annual growth projected

for other public timberland

Projections

Region 1997 2002 2010 2020 2030 2040 2050

Million cubic feet

Northeast:

 Removals 45 51 50 54 54 55 55

 Inventory 10,158 11,018 11,838 12,747 13,761 14,735 15,693

 Net annual growth 151 194 138 150 154 151 150

North Central:

 Removals 231 189 172 180 181 180 179

 Inventory 11,430 11,538 13,561 15,546 17,446 19,326 21,255

 Net annual growth 237 305 369 375 369 370 371

Southeast:

 Removals 39 54 52 58 67 76 81

 Inventory 4,062 4,262 4,418 4,595 4,680 4,695 4,664

 Net annual growth 100 106 75 76 77 78 78

South Central:

 Removals 53 51 54 67 79 92 101

 Inventory 4,956 5,728 6,095 7,110 7,909 8,499 8,859

 Net annual growth 181 146 165 161 153 141 133
14

GENERAL TECHNICAL REPORT PNW-GTR-717

constructed and the results included in table 3. Alaska’s softwood removals represent less than 1 percent of the total. It should be noted that although smaller in area

than the Northern and Southern regions, the Pacific Northwest West region tops

other public softwood production in 2050 with removals that represent 32 percent

of the United States total. The combined Rocky Mountain region comes in at

second place with 21 percent of the removals in 2050. Meanwhile, when it comes

to hardwood production, the East shows its dominance with 91 percent of all other

public hardwood removals. Whereas most regions show stable hardwood removals

projections, the Southeast and South Central regions show increases of 50 and 98

Table 4—Hardwood inventory, annual removals, and net annual growth projected

for other public timberland (continued)

Projections

Region 1997 2002 2010 2020 2030 2040 2050

Million cubic feet

Rocky Mountains:

 Removals 2 1 3 3 3 3 3

 Inventory 823 827 746 866 985 1,099 1,222

 Net annual growth 45 18 13 15 15 15 14

Pacific Southwest:a

 Removals 1 1 1 1 1 1 1

 Inventory 319 319 332 384 433 478 512

 Net annual growth 5 5 4 5544

Pacific Northwest:

 Removals 13 33 27 29 31 32 34

 Inventory 2,846 2,846 3,331 3,828 4,377 4,894 5,389

 Net annual growth 74 64 77 82 85 84 82

Alaska:

 Removals 1 1 1 1 1 1 1

 Inventory 1,930 2,260 2,696 3,400 4,105 4,810 5,514

 Net annual growth 49 72 72 72 72 72 72

United States:

 Removals 386 381 361 394 418 441 456

 Inventory 36,524 38,798 43,017 48,476 53,696 58,536 63,108

 Net annual growth 841 910 913 936 930 915 904

Note: In 1991, Native American lands were transferred to nonindustrial private forest; previously

they were in other public.

Note: Historical harvest data are estimates of harvest trends and differ somewhat from the estimates

of actual consumption shown in some tables. For the projection years, the data show the average

volume that would be harvested given the assumptions of the study.

a

 Pacific Southwest excludes Hawaii.

Source: Haynes and others 2007.
15

Projecting Other Public Inventories for the 2005 RPA Timber Assessment Update

percent, respectively. This increase in removals is concurrent with increasing

demand for hardwoods on private land in the South (Haynes and others 2007).

Most inventories on other public timberlands are expected to rise. Nationally,

both softwood and hardwood inventories are projected to increase over 60 percent

by 2050. As shown in figure 4, the age class distribution of inventory shifts to the

right as stands age faster than they are harvested. Regionally, the projection varies

for softwoods, ranging from a 3 percent loss in Pacific Northwest East (ponderosa

pine region) to a 100 percent gain in North Central region. The most variation seen

for softwoods is in the Pacific Northwest East where inventories are expected to

decrease until 2030 and then increase slowly, when the level of removals is expected to be in balance with the amount of growth in that region. Hardwood inventory is projected to increase across all regions, from 9 percent in Southeast to 89

percent in the Pacific Northwest region.

The initial (2002) distribution of inventory by age in the West (fig. 5a) shows

two large peaks, one at age 0 to 10 (mid-age 5) and the other at age 80 to 90 (midage 85). The relatively large number of acres in the first age class represents both

poorly stocked or recently regenerated areas. The drop in area around age 15 and

25 suggests there was a decade of high harvesting, fire mortality, and/or a recent

history of poor regeneration. There is a sharp decline in area past age 100, suggesting that harvesting has been concentrated in stands age 100 or greater.

Figure 4—Initial and projected distributions (2050) of other public timberland area by age.

Note: The bump of acres at age class 175 represent an aggregation of all stands in the north of

175 and older

Nationally, both

softwood and hardwood inventories

are projected to

increase over 60

percent by 2050.
16

GENERAL TECHNICAL REPORT PNW-GTR-717

Figure 5a—Initial and projected distribution of other public timberland area in the Western United

States.

Figure 5b—Initial and projected distribution of other public timberland area in the Northern United

States.
17

Projecting Other Public Inventories for the 2005 RPA Timber Assessment Update

During the projection, harvesting occurred over a range of age classes with

minimums set around age 85. Under age 60, there are roughly the same number

of acres as there were at the start of the projection, but past age 100 there are more

as harvest levels have been less than growth.

In 2002, the other public inventory in the North is nearly all less than 110 years

old (see fig. 5b). The spike at 175 represents all area supporting stands older than

170, and there are as many acres there as there are between ages 100 and 170.

This could indicate a history of harvest by age 100 for most of the ownership while

some areas continue to support late-successional stands. The projection moves the

25- to 85-year-old bulge of inventory ahead, harvesting over the range from 40 to

60. The resulting inventory has significantly fewer acres less than age 50, indicating

less harvest than in the last 50 years, and the gap between age 100 and 170 has been

nearly filled. In all, the projection shows a more balanced representation across

nearly all age classes.

Nearly all of the initial Southern other public inventory is less than 60 years

old (see fig. 5c). Southern rotations are much shorter than anywhere else, as it can

be seen that after age 40 the area decreases dramatically. By 2050 the area less than

age 50 declines from 95 to 45 percent, while the area over 50 increases significantly. This is an indication that harvest in the next 50 years will be less than it has

been in recent history. Like the North, the projected inventory shows more balance

among a greater range of age classes.

Figure 5c—Initial and projected distribution of other public timberland area in the Southern United

States.
18

GENERAL TECHNICAL REPORT PNW-GTR-717

Finally, these results depend on assumptions about management objectives and

harvest behaviors of a diverse collection of county, state, and federal agencies who

manage the other public timberlands. Each of these agencies differs in purpose,

legislative mandates, and relations to stakeholder groups. For example, harvests

from Oregon state lands in 2005 were 341 million board feet, but this could change

dramatically (say 50 percent) depending on future state forest policies, outcomes

from planning processes, or court cases.

Overall, the mid-age classes (stands from age 70 to less than 150) are expected

to increase dramatically from 26 percent in 2002 to 48 percent in 2050 (shown in

fig. 4), timberland area for stands over 150 is expected to be stable. In 2002, 5.6

percent of the other public timberlands had stands over 150 years. This is only

expected to increase to 7 percent by 2050 under the current removal and disturbance assumptions, and most of that increase comes in the Western region, from 8

percent to 12 percent.

Discussion

Figure 6 shows a comparison between the inventory volume projections on other

public timberland from the 2000 RPA timber assessment (Haynes 2003) that used

the simple growth-drain identity and the current 2005 RPA timber assessment

update, which applies the same inventory projection system to other public timberland as used for private and National Forest System timberlands. In general,

improving the rigor of inventory projections for other public ownership does not

change much of the essential projection of total inventory volume. That is, they are

projected to increase for both hardwood and softwoods. The 2000 RPA timber

inventory levels on other public timberland shown in figure 6 are higher for

softwoods (9 percent) but lower for hardwoods (12 percent) than the levels in 2005

RPA timber assessment update.

This 2005 RPA update approach does, however, produce other information

that leads to a richer understanding of the resource conditions on other public timberlands. For example, we can use several indicators from the Montreal Process

(Montreal Process Technical Advisory Committee 2000) to describe the overall

condition of this ownership. These indicators are inventory volumes by hardwood

and softwood, the growth removals ratio, and proportions by seral stages. Examining these gives us a broad-scale understanding of both timber and ecological conditions. In general, these indicators suggest well-managed forests where excess

growth leads to higher inventory levels and proportionally older stands (especially

those in the mature seral stage).

This 2005 RPA update approach does,

however, produce

other information

that leads to a richer

understanding of

the resource conditions on other public

timberlands.
19

Projecting Other Public Inventories for the 2005 RPA Timber Assessment Update

The structure of this inventory is projected to change over the projection period

(table 5). Currently, the other public ownership is about the same as the structure

for all private timberlands with the exception of having a higher proportion (15

percent more) young sawtimber stands. Over time, like the other ownerships, other

public timberlands tend to age with a reduction in the area of young stands (table

5). The rate of this progression is faster than for private timberlands but substantially less than the progression on national forest timberlands where the area in

younger (seedlings, poles-saplings, and young seral stages) stands drops from

42 to 24 percent by 2050. This suggests that a larger proportion of other public

timberlands follow some sort of sustained yield or structure-based management

approach to forest regulation rather than the ecosystem management approaches

now common on national forest timberlands.

The growth and aging of the inventories is due in part to the relatively high

growth-to-drain ratios for softwoods and hardwoods. These can be summarized

from tables 3 and 4 and shown as follows:

Species 2002 2050

Softwoods 2.15 1.79

Hardwoods 2.18 1.98

Figure 6—Other public inventory comparing original and updated data.
20

GENERAL TECHNICAL REPORT PNW-GTR-717

Table 5–Other public timberlands by seral stages

Seral stage

Species and Poles- Old

area Seedlinga saplingsb Youngc Matured maturee Total

Softwood: Thousand acres

North—

2000 657 1,221 2,404 1,627 362 6,270

 2010 688 1,058 2,001 2,288 235 6,270

 2020 682 657 2,099 2,605 228 6,270

 2030 514 688 1,590 3,267 210 6,270

 2040 442 682 1,345 3,505 296 6,270

 2050 399 514 1,058 3,925 374 6,270

South—

 2000 523 1,191 2,336 381 5 4,436

 2010 293 822 2,547 773 1 4,436

 2020 294 578 2,013 1,544 8 4,436

 2030 277 586 1,400 2,160 12 4,436

 2040 296 565 1,164 2,327 84 4,436

 2050 303 597 1,151 2,107 278 4,436

 West—

 2000 1,109 1,469 3,262 3,643 979 10,463

 2010 706 1,996 2,930 3,602 1,228 10,463

 2020 677 2,335 2,426 3,870 1,156 10,463

 2030 626 2,493 2,152 3,644 1,549 10,463

 2040 583 2,010 2,578 3,772 1,521 10,463

 2050 550 1,885 2,703 3,451 1,874 10,463

Hardwood:

 North—

 2000 810 3,287 6,654 4,619 1,260 16,630

 2010 1,104 3,300 4,178 6,936 1,112 16,630

 2020 924 3,057 4,050 7,452 1,147 16,630

 2030 817 2,838 3,287 8,577 1,112 16,630

 2040 726 2,845 3,300 8,335 1,425 16,630

 2050 671 2,467 3,057 8,942 1,492 16,630
21

Projecting Other Public Inventories for the 2005 RPA Timber Assessment Update

At present, growth is more than twice harvest levels. But in both cases the ratio

is projected to drop because harvest increases at a somewhat faster rate than the rate

for growth. Growth rates for both fiber types start to decline (after peaking in

2020) reflecting higher proportions of the inventories moving to slower growing

older age classes. In the ATLAS approach, growth rates are expressed by age

classes, and net growth drops in older age classes reflecting maturing trees and

higher mortality (see app. tables 6-14).

These increases in inventories (from 1,031 to 1,665 cubic feet per acre for

softwoods) pose additional management challenges especially in the West where

there is a need to manage fuel conditions on public lands. These projections suggest

that fuel loading will only increase and, without increased management, pose

greater challenges in the future. The volumes involved suggest that fuel management strategies will be complicated by the need for repeated treatments.

Table 5–Other public timberlands by seral stages (continued)

Seral stage

Species and Poles- Old

area Seedlinga saplingsb Youngc Matured maturee Total

Softwood: Thousand acres

South—

 2000 463 1,156 3,691 95 140 5,545

 2010 175 915 4,128 210 117 5,545

 2020 201 540 3,812 862 129 5,545

 2030 220 620 2,576 1,947 182 5,545

 2040 242 671 1,721 2,396 516 5,545

 2050 244 717 1,538 1,582 1,465 5,545

West—

 2000 142 346 286 744 111 1,629

 2010 74 336 297 807 114 1,629

 2020 63 286 276 886 118 1,629

 2030 55 279 194 971 130 1,629

 2040 48 192 212 1,047 131 1,629

 2050 43 165 216 1,005 199 1,629

a

 Seedlings seral stage = age 5 all regions and fiber except North softwood, which includes 5 to 15.

b

 Poles and saplings seral stage = age 25 to 35 North softwood; 15 to 35 North hardwood; 10 to 15

South softwood; 10 to 20 South hardwood; 15 to 35 West hardwood and softwood.

c

 Young sawtimber seral stage = age 45 to 65 North; 20 to 35 South softwood; 25 to 55 South

hardwood; 45 to 75 West softwood; 45 to 55 West hardwood.

d

 Mature sawtimber seral stage = age 75 to 135 North; 40 to 75 South softwood; 60 to 75 South

hardwood; 85 to 135 West softwood; 65 to 135 West hardwood.

e

 Old mature sawtimber seral stage = age 145+ North; 80+ South; 145+ West.

Source: Haynes and others 2007.

These projections

suggest that fuel

loading will only

increase and, without increased management, pose

greater challenges

in the future.
22

GENERAL TECHNICAL REPORT PNW-GTR-717

In general, the various indicators of other public inventories suggest a group of

well-managed timberlands. Many public land managers are active participants in

efforts to demonstrate how the United States is making progress toward sustainable

forest management. These are also the public timberlands most frequently encountered by residents in the Eastern United States. In that context, they will play a

significant role in shaping perceptions of the links between forest management and

the flow of forest goods and services.

Metric Equivalents

When you know: Multiply by: To find:

Acres 0.405 Hectares

Cubic feet .0283 Cubic meters

Cubic feet per acre .07 Cubic meters per hectare

Literature Cited

Adlard, P.G. 1995. Myth and reality in growth estimation. Forest Ecology and

Management. 71(3): 171–176.

Davis, L.S.; Johnson, K.N. 1987. Forest management. New York: McGraw-Hill,

Inc. 790 p.

Forest and Rangeland Renewable Resources Planning Act of 1974 [RPA];

16 U.S.C. 1601 (note).

Haynes, R.W., coord. 1990. An analysis of the timber situation in the United

States: 1989–2040. Gen. Tech. Rep. RM-199. Fort Collins, CO: U.S.

Department of Agriculture, Forest Service, Rocky Mountain Forest and Range

Experiment Station. 286 p.

Haynes, R.W., tech. coord. 2003. An analysis of the timber situation in the

United States: 1952–2050. Gen. Tech. Rep. PNW-GTR-560. Portland, OR:

U.S. Department of Agriculture, Forest Service, Pacific Northwest Research

Station. 254 p.

Haynes, R.W.; Adams, D.M.; Alig, R.J.; Ince, P.J.; Mills, J.R.; Zhou, X. 2007.

The 2005 timber assessment update. Gen. Tech. Rep. PNW-GTR-699.

Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific

Northwest Research Station. 212 p.
23

Projecting Other Public Inventories for the 2005 RPA Timber Assessment Update

Mills, J.R. 1990. Developing ATLAS growth parameters from forest inventory

plots. In: LaBau, V.; Cunia, T., eds. State-of-the-art methodology of forest

inventory: a symposium proceedings. Gen. Tech. Rep. PNW-GTR-263.

Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific

Northwest Research Station: 112–118.

Mills, J.R.; Kincaid, J.C. 1992. The aggregate timberland assessment system—

ATLAS: a comprehensive timber projection model. Gen. Tech. Rep. PNWGTR-281. Portland, OR: U.S. Department of Agriculture, Forest Service,

Pacific Northwest Research Station. 160 p.

Mills, J.R.; Zhou, X. 2003. Projecting national forest inventories for the 2000

RPA timber assessment. Gen. Tech. Rep. PNW-GTR-568. Portland, OR:

U.S. Department of Agriculture, Forest Service, Pacific Northwest Research

Station. 58 p.

Montreal Process Technical Advisory Committee. 2000. Technical notes, criteria

1-6. http://www.mpci.org/tac/mexico/tn1-6_e.html. (October 2006).

Oliver, C.D.; Larson, B.C. 1990. Forest stand dynamics. New York: McGrawHill, Inc. 467 p.

Smith, B.W.; Miles, P.D.; Vissage, J.S.; Pugh, S.A. 2004. Forest resources of the

United States, 2002. Gen. Tech. Rep. NC-241. St. Paul, MN: U.S. Department

of Agriculture, Forest Service, North Central Research Station. 137 p.

U.S. Department of Agriculture, Forest Service [USDA FS]. 1982. An analysis

of the timber situation in the United States 1952–2030. Forest Resour. Rep. 23.

Washington, DC. 272 p. [plus appendicies].
24

GENERAL TECHNICAL REPORT PNW-GTR-717

Appendix

Table 6—Yield tables for other public Pacific Northwest West region by forest type

Western Fir and Hardwood

Age class Douglas-fir hemlock spruce Red alder mix

Cubic feet per acre

5 0 00 00

15 208 150 72 267 47

25 1,661 1,754 779 1,265 657

35 3,774 4,470 1,926 2,866 1,724

45 5,876 7,262 3,057 4,530 2,798

55 7,849 9,938 4,093 6,166 3,798

65 9,662 12,440 5,013 7,748 4,704

75 11,309 14,750 5,812 9,273 5,510

85 12,794 16,866 6,497 10,747 6,222

95 14,128 18,794 7,074 12,180 6,847

105 15,325 20,548 7,554 13,583 7,394

115 16,399 22,139 7,947 14,971 7,874

125 17,367 23,584 8,266 16,323 8,298

135 18,245 24,900 8,523 17,613 8,678

145 19,052 26,104 8,731 18,843 9,026

155 19,805 27,214 8,903 20,013 9,354

165 20,523 28,250 9,051 21,123 9,676

175 21,223 29,229 9,191 22,173 10,004

185 21,924 30,171 9,334 23,163 10,351

195 22,645 31,095 9,494 24,093 10,729

205 23,405 32,021 9,685 24,963 11,152

215 24,222 32,968 9,921 25,773 11,634

225 25,114 33,955 10,215 26,523 12,186

235 26,102 35,003 10,581 27,213 12,822

245 27,204 36,132 11,032 27,843 13,555

255 28,438 37,360 11,583 28,413 14,399
25

Projecting Other Public Inventories for the 2005 RPA Timber Assessment Update

Table 7—Yield tables for other public Pacific Northwest East region by forest type

Ponderosa Douglas-fir

Age class pine and larch True fir Lodgepole pine Hardwood

Cubic feet per acre

5 0 00 00

15 21 85 0 95 32

25 279 581 217 583 261

35 747 1,287 745 1,168 585

45 1,257 2,055 1,392 1,722 891

55 1,774 2,826 2,063 2,234 1,166

65 2,287 3,571 2,711 2,706 1,413

75 2,790 4,274 3,308 3,142 1,631

85 3,278 4,927 3,840 3,544 1,825

95 3,750 5,527 4,302 3,916 1,996

105 4,204 6,075 4,691 4,261 2,145

115 4,640 6,573 5,010 4,580 2,275

125 5,057 7,024 5,264 4,876 2,388

135 5,454 7,435 5,459 5,150 2,483

145 5,830 7,812 5,602 5,403 2,563

155 6,186 8,160 5,704 5,637 2,628

165 6,522 8,489 5,773 5,854 2,680

175 6,836 8,805 5,822 6,053 2,718

185 7,129 9,117 5,860 6,237 2,744

195 7,400 9,434 5,901 6,405 2,758

205 7,650 9,765 5,956 6,559 2,763

215 7,879 10,118 6,037 6,699 2,763

225 8,086 10,503 6,159 6,825 2,763

235 8,271 10,930 6,333 6,939 2,763

245 8,434 11,408 6,574 7,041 2,763

255 8,576 11,948 6,895 7,132 2,763
26

GENERAL TECHNICAL REPORT PNW-GTR-717

Table 8—Yield tables for the Pacific Southwest region by forest type

Douglas-fir

Pinyon and Ponderosa Mixed

Age class juniper True fir Hardwood redwood pine conifer

Cubic feet per acre

5 0 00 0 00

15 0 28 0 58 5 29

25 11 196 15 397 66 159

35 26 463 370 832 205 349

45 47 840 1,090 1,250 415 636

55 73 1,343 1,826 1,660 689 1,028

65 103 1,954 2,493 2,076 1,024 1,523

75 137 2,652 3,072 2,510 1,411 2,114

85 173 3,419 3,564 2,970 1,845 2,793

95 211 4,239 3,979 3,461 2,321 3,548

105 251 5,099 4,328 3,987 2,832 4,368

115 291 5,989 4,620 4,552 3,372 5,240

125 332 6,899 4,868 5,156 3,935 6,152

135 372 7,822 5,082 5,801 4,516 7,090

145 410 8,750 5,269 6,487 5,107 8,041

155 447 9,678 5,440 7,214 5,703 8,990

165 481 10,600 5,600 7,980 6,299 9,924

175 511 11,511 5,758 8,785 6,887 10,828

185 537 12,408 5,919 9,627 7,463 11,687

195 558 13,286 6,089 10,505 8,020 12,488

205 574 14,143 6,273 11,417 8,551 13,216

215 584 14,974 6,478 12,360 9,052 13,856

225 587 15,778 6,706 13,334 9,515 14,394

235 587 16,551 6,961 14,335 9,936 14,814

245 587 17,291 7,249 15,361 10,307 15,102

255 587 17,997 7,572 16,410 10,624 15,242
27

Projecting Other Public Inventories for the 2005 RPA Timber Assessment Update

Table 9—Yield tables for the Rocky Mountain North region by forest type

HighDouglas- Ponderosa Fir- Lodgepole elevation

Age class fir pine spruce pine Hardwood softwoods

Cubic feet per acre

5 0 00 0 0 0

15 30 72 0 63 20 27

25 266 372 260 365 132 153

35 665 679 880 762 309 312

45 1,137 977 1,626 1,239 589 499

55 1,641 1,262 2,390 1,784 960 713

65 2,158 1,531 3,118 2,383 1,334 951

75 2,674 1,783 3,782 3,022 1,660 1,210

85 3,183 2,021 4,365 3,689 1,915 1,486

95 3,680 2,246 4,862 4,369 2,093 1,778

105 4,163 2,458 5,271 5,050 2,201 2,082

115 4,629 2,662 5,596 5,717 2,253 2,395

125 5,078 2,858 5,842 6,358 2,272 2,715

135 5,511 3,050 6,018 6,959 2,276 3,039

145 5,929 3,240 6,133 7,506 2,276 3,363

155 6,333 3,431 6,199 7,987 2,276 3,686

165 6,725 3,626 6,227 8,387 2,276 4,004

175 7,106 3,827 6,233 8,694 2,276 4,315

185 7,479 4,038 6,233 8,894 2,276 4,615

195 7,846 4,261 6,233 8,973 2,276 4,902

205 8,210 4,499 6,233 8,981 2,276 5,172

215 8,573 4,756 6,233 8,981 2,276 5,424

225 8,939 5,034 6,233 8,981 2,276 5,654

235 9,309 5,337 6,233 8,981 2,276 5,860

245 9,688 5,667 6,233 8,981 2,276 6,038

255 10,078 6,028 6,233 8,981 2,276 6,185
28

GENERAL TECHNICAL REPORT PNW-GTR-717

Table 10—Yield tables for the Rocky Mountain South region by forest type

HighAge Ponderosa Lodgepole Pinyon elevation

class Douglas-fir pine Fir-spruce pine Hardwood juniper softwoods

Cubic feet per acre

5 0 0 0 0 00 0

15 15 0 39 5 5 3 0

25 104 33 254 25 65 26 41

35 242 122 553 46 202 62 234

45 409 245 901 116 407 108 584

55 597 388 1,279 287 669 159 994

65 799 542 1,677 562 978 213 1,415

75 1,013 704 2,090 930 1,323 270 1,816

85 1,234 867 2,513 1,372 1,695 328 2,182

95 1,462 1,031 2,942 1,867 2,083 386 2,502

105 1,692 1,192 3,375 2,389 2,478 444 2,771

115 1,925 1,349 3,809 2,909 2,868 500 2,989

125 2,159 1,500 4,243 3,400 3,243 554 3,156

135 2,391 1,645 4,675 3,830 3,595 606 3,275

145 2,621 1,781 5,105 4,169 3,911 654 3,349

155 2,848 1,909 5,530 4,386 4,182 699 3,385

165 3,070 2,028 5,951 4,525 4,399 739 3,394

175 3,286 2,136 6,367 4,650 4,550 774 3,394

185 3,495 2,233 6,776 4,765 4,625 804 3,394

195 3,697 2,320 7,179 4,870 4,643 829 3,394

205 3,889 2,395 7,574 4,965 4,643 846 3,394

215 4,072 2,457 7,961 5,050 4,643 857 3,394

225 4,245 2,507 8,340 5,125 4,643 861 3,394

235 4,405 2,545 8,710 5,190 4,643 861 3,394

245 4,553 2,569 9,071 5,245 4,643 861 3,394

255 4,688 2,580 9,423 5,290 4,643 861 3,394
29

Projecting Other Public Inventories for the 2005 RPA Timber Assessment Update

Table 11—Yield tables for the North Central Plains States region by forest type

Oak and Lowland Maple and

Age class Pine Oak pine hickory hardwood beech

Cubic feet per acre

5 0 00 00

15 116 65 34 40 15

25 575 406 191 271 159

35 1,000 828 387 603 424

45 1,366 1,239 617 977 750

55 1,682 1,618 874 1,368 1,109

65 1,956 1,959 1,153 1,762 1,484

75 2,192 2,259 1,448 2,148 1,865

85 2,397 2,515 1,753 2,519 2,246

95 2,574 2,727 2,062 2,872 2,619

105 2,724 2,893 2,370 3,200 2,982

115 2,851 3,014 2,671 3,502 3,330

125 2,958 3,088 2,959 3,775 3,662

135 3,044 3,115 3,228 4,016 3,974

145 3,112 3,117 3,472 4,224 4,264

155 3,163 3,117 3,686 4,397 4,531

165 3,199 3,117 3,863 4,534 4,774

175 3,219 3,117 3,999 4,634 4,991

185 3,226 3,117 4,087 4,695 5,181

195 3,226 3,117 4,121 4,717 5,344

205 3,226 3,117 4,124 4,718 5,477

215 3,226 3,117 4,124 4,718 5,581

225 3,226 3,117 4,124 4,718 5,654

235 3,226 3,117 4,124 4,718 5,697

245 3,226 3,117 4,124 4,718 5,710

255 3,226 3,117 4,124 4,718 5,710
30

GENERAL TECHNICAL REPORT PNW-GTR-717

Table 12—Yield tables for the North Central Lake States region by forest type

Age Spruce and Swamp Oak and Lowland Maple and Aspen and

class Jack pine Red pine White pine balsam fir conifer hickory hardwood beech birch

Cubic feet per acre

5 0 00 00 0 00 0

15 30 103 31 53 21 33 34 48 38

25 228 775 272 315 119 232 216 312 285

35 538 1,688 689 668 258 527 468 686 668

45 899 2,544 1,201 1,092 444 874 760 1,115 1,119

55 1,284 3,315 1,768 1,565 664 1,252 1,079 1,576 1,604

65 1,677 4,003 2,370 2,065 909 1,647 1,413 2,055 2,106

75 2,068 4,614 2,992 2,572 1,171 2,054 1,758 2,542 2,613

85 2,450 5,154 3,624 3,063 1,446 2,466 2,105 3,030 3,116

95 2,817 5,631 4,259 3,517 1,728 2,878 2,452 3,516 3,609

105 3,164 6,049 4,891 3,914 2,014 3,289 2,794 3,995 4,087

115 3,490 6,412 5,515 4,232 2,302 3,695 3,127 4,464 4,546

125 3,791 6,726 6,128 4,449 2,589 4,093 3,447 4,921 4,983

135 4,064 6,994 6,726 4,544 2,874 4,484 3,752 5,364 5,395

145 4,308 7,217 7,307 4,559 3,155 4,864 4,038 5,791 5,781

155 4,521 7,401 7,868 4,559 3,431 5,233 4,302 6,200 6,137

165 4,702 7,545 8,408 4,559 3,700 5,589 4,541 6,591 6,463

175 4,849 7,654 8,925 4,559 3,961 5,932 4,753 6,962 6,757

185 4,962 7,728 9,417 4,559 4,213 6,261 4,934 7,312 7,018

195 5,039 7,770 9,882 4,559 4,455 6,575 5,082 7,641 7,244

205 5,080 7,783 10,321 4,559 4,688 6,874 5,194 7,947 7,435

215 5,091 7,783 10,731 4,559 4,909 7,156 5,268 8,230 7,589

225 5,091 7,783 11,112 4,559 5,119 7,421 5,301 8,490 7,707

235 5,091 7,783 11,462 4,559 5,317 7,670 5,307 8,725 7,786

245 5,091 7,783 11,782 4,559 5,501 7,900 5,307 8,935 7,827

255 5,091 7,783 12,069 4,559 5,673 8,113 5,307 9,120 7,828
31

Projecting Other Public Inventories for the 2005 RPA Timber Assessment Update

Table 13—Yield tables for the Northeast region by forest type

Loblolly/

shortleaf/

Jack/red/ Spruce and oak/gum/ Elm/ash/red Maple/

Age class white pine balsam fir cypress Oak pine Oak hickory maple beech/birch Aspen/birch

Cubic feet per acre

5 0 000 0 0 0 0

15 0 0 20 0 0 0 0 0

25 204 51 184 0 29 126 63 14

35 673 215 449 66 141 411 256 128

45 1,222 468 743 226 327 738 546 365

55 1,788 765 1,050 432 550 1,077 880 660

65 2,344 1,092 1,364 664 793 1,414 1,239 990

75 2,873 1,439 1,684 913 1,051 1,740 1,614 1,343

85 3,359 1,804 2,008 1,176 1,319 2,050 1,999 1,712

95 3,793 2,184 2,334 1,447 1,594 2,339 2,392 2,093

105 4,164 2,578 2,663 1,726 1,875 2,601 2,791 2,484

115 4,462 2,986 2,993 2,011 2,161 2,833 3,193 2,882

125 4,679 3,407 3,325 2,300 2,450 3,030 3,599 3,287

135 4,806 3,841 3,658 2,593 2,743 3,190 4,008 3,696

145 4,845 4,289 3,991 2,890 3,038 3,307 4,419 4,110

155 4,845 4,751 4,326 3,189 3,336 3,379 4,831 4,528

165 4,845 5,228 4,661 3,491 3,635 3,404 5,245 4,949

175 4,845 5,720 4,997 3,795 3,936 3,404 5,659 5,372

Table 14—Yield tables for the Southern (South Central and Southeast) regions by

forest type

Upland Bottomland

Age class Planted pine Natural pine Oak pine hardwood hardwood

Cubic feet per acre

5 0 00 00

10 331 273 195 167 140

15 1,167 525 397 303 284

20 2,067 863 628 483 467

25 2,782 1,222 848 666 649

30 3,211 1,554 1,104 860 830

35 3,360 1,875 1,384 1,091 1,049

40 3,439 2,177 1,675 1,348 1,318

45 3,517 2,462 1,950 1,630 1,582

50 3,595 2,736 2,202 1,901 1,830

55 3,675 2,978 2,450 2,164 2,091

60 3,755 3,200 2,710 2,414 2,374

65 3,835 3,407 2,923 2,652 2,664

70 3,915 3,614 3,127 2,880 2,940

75 3,995 3,782 3,352 3,082 3,180

80 4,075 3,960 3,539 3,278 3,400

85 4,155 4,138 3,707 3,465 3,677

90 4,235 4,280 3,891 3,632 3,986
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May 2007