United States 

Department of 

Agriculture

Forest 

Service

North Central

Research Station

General

Technical Report

NC-264

A Revised Managers

Handbook for 

Red Pine in the 

North Central Region

Compiled and Edited by:

Daniel W. Gilmore and Brian J. Palik

A Joint Publication of the

USDA Forest Service and University of Minnesota
Cover Photographs: (Left) A 140 year old red pine stand on the Cutfoot Experimental

Forest in Northern Minnesota, (center) an old growth red pine stand in northern

Minnesota circa 1920, and (right) a 40 year old red pine plantation on the Kellogg

Experimental Forest in central lower Michigan. (USDA Forest Service)
Contents

I

List of Contributors & Reviewers ............................................................................................ II

List of External Reviewers....................................................................................................... III

Management Guides for Red Pine — Their Evolution and Why We Need Them ................... 1

Managing Stands in the Context of Ownership Goals ............................................................. 2

Ecological and Silvical Highlights of Red Pine ......................................................................... 3

Red Pine Management Considerations..................................................................................... 4

Management Goals, Objectives, and Implications ......................................................... 4

Genetic Considerations in Red Pine Management ......................................................... 8

Establishment Considerations........................................................................................ 9

Regenerating Red Pine ................................................................................................. 13

Managing Established Stands....................................................................................... 19

Managing Red Pine Stands for Ecological Complexity................................................. 23

Incorporating Ecological Complexity into Red Pine Management............................... 24

Damaging Agents ................................................................................................................... 29

Major Diseases of Red Pine.......................................................................................... 29

Avoiding Insect Related Problems................................................................................ 36

References .............................................................................................................................. 37

Appendix: Useful Forestry Terminology ................................................................................ 39

Appendix A.—Site Index Curves for Red Pine From Different Regions of

North America ....................................................................................................................... 43

Appendix B.—Growth and Yield Equations and Tables for Red Pine Basal Area, 

Cubic Foot, Cord, and Board-foot Volume Growth ............................................................... 47 

Appendix C.—Rotation Ages Calculated at Various Site Indices and Densities 

for Red Pine ........................................................................................................................... 55

North Central

Research Station 

USDA Forest Service

1992 Folwell Avenue

Saint Paul,

Minnesota, 55108

Published 2005

www.ncrs.fs.fed.us
II

John W. Benzie, USDA Forest Service, North Central Research Station (retired)

Charles R. Blinn, University of Minnesota

Thomas E. Burk, University of Minnesota

Thomas R. Crow, USDA Forest Service, Research and Development

Andrew J. David, University of Minnesota

Daniel W. Gilmore, University of Minnesota

Amy L. Harder, SAPPI, Cloquet, Minnesota

Howard M. Hoganson, University of Minnesota

Beth Jacqmain, Aitkin County Land Development, Aitkin, Minnesota

Brad Jones, Itasca County Land Department, Grand Rapids, Minnesota

Steven A. Katovich, USDA Forest Service, Northeastern Area State and Private Forestry

Allen L. Lundgren, USDA Forest Service, North Central Research Station (retired)

Timothy J. Mack, Consulting Forester, Hanover, Maine

Michael E. Ostry, USDA Forest Service, North Central Research Station

Brian J. Palik, USDA Forest Service, North Central Research Station

Eric K. Zenner, University of Minnesota

List of Contributors & Reviewers 
III

List of External Reviewers

Thomas J. Dean, Louisiana State University

Alan R. Ek, University of Minnesota

Alan Jones, Minnesota Department of Natural Resources

Michael A. Kilgore, University of Minnesota

Thomas McCann, USDA Forest Service, Superior National Forest

Linda M. Nagel, Michigan Technological University

H. Michael Rauscher, USDA Forest Service, Southeastern Research Station

Scott D. Roberts, Mississippi State University

Alan Saberniak, USDA Forest Service, Hiawatha National Forest

Ronald W. Severs, University of Minnesota

Gary Swanson, USDA Forest Service, Chippewa National Forest

Myra Theimer, USDA Forest Service, Superior National Forest

Gary Wyckoff, Plum Creek, Escanaba, Michigan

John C. Zasada, USDA Forest Service, North Central Research Station (retired)

1

Management Guides for Red Pine — 

Their Evolution and Why We Need Them 

Red pine (Pinus resinosa Ait.), also known as Norway pine has been the most widely planted

species in the Lake States region of North America over the past 70 years. As a result, the red

pine cover type in the Lake States has increased more than fivefold to almost 1.9 million acres.

Because of its widespread occurrence and economic value, red pine has long received close

attention from researchers and forest managers. In 1914, Theodore S. Woolsey, Jr., and

Herman H. Chapman published a 42-page U.S. Department of Agriculture Bulletin entitled,

“Norway Pine in the Lake States.” This early management guide, based on careful observations

and measurements by field foresters, served as the primary guide for managing red pine stands

for more than 30 years.

During the latter two-thirds of the 20th century, employees of the USDA Forest Service, State

governments, universities, the Canadian government, and others established long-term studies

of red pine. As measurements and results from these studies became available, red pine guides

were periodically revised and updated. Most of these guides focused on establishing and managing red pine stands to improve timber growth.

Since the late 1900s, however, the objectives of management, especially on public lands, have

broadened beyond timber output. Land managers are now being challenged to address questions not answered by existing guides. Despite their widespread use, the red pine management

guides produced to date have several deficiencies: 1) They focus on managing the stand as an

isolated unit, without considering landscape concerns; 2) they focus almost exclusively on timber production, with little attention to recreation, aesthetics, wildlife, water, or other objectives;

3) they apply primarily to pure, single-aged red pine stands and have little to say about stands

of mixed species or ages; 4) they are poorly linked to landscape ecology and to vegetation and

soil types; and 5) they classify site productivity of red pine stands almost entirely with site

index. 

Because existing guides no longer meet the needs of contemporary land managers, we have

developed this new handbook for managing red pine with multiple objectives in mind. As a

multidisciplinary team of public and private foresters, researchers, and practitioners, we have

attempted to eliminate some of the deficiencies noted above by bringing up-to-date information from many disciplines to bear on a wider range of red pine management issues.

About the Authors:

Daniel Gilmore is an

Assistant Professor of

Silviculture with the

University of Minnesota,

St. Paul, Minnesota.

Brian Palik is a Project

Leader and Research

Ecologist with the USDA

Forest Service, North

Central Research Station,

Grand Rapids, Minnesota
2

Managing Stands in the Context of Ownership Goals

While silviculture is applied at the scale of forest stands, it is important to consider the implications of stand management within the context of varying ownership goals across the landscape. A useful approach for doing this is to look at the different goals of management, including production management, extensive management, and reserve management, and how and

where these goals are applied. In principle, these are not discrete categories, but general treatment groups that overlap and grade into one another. For our purposes, intensity refers to the

degree of disturbance associated with silvicultural treatments, and management goal is defined

by the degree to which producing wood fiber is the driving objective. 

Production management is often associated with high capital investments to ensure rapid dominance by desired species. This includes treatments such as thinning to maximize growth and

pruning to improve the quality of wood. Fertilization, irrigation, site preparation, control of competition, and planting of genetically improved stock are tools used to achieve these ends. The

establishment and tending of plantations is typically considered to be production management. 

Extensive management is the broadest category among the three and has been the most common approach in North Central forests. Compared with production management, extensive

management applies over larger areas and has lower impacts, lower costs, and lower return on

capital investment. Even-aged management in natural forests falls within extensive management, as do individual tree and small group selection prescriptions. It may involve managing

on extended rotations for old growth characteristics and timber, increased ecological complexity,

and heterogeneity in forests that are also managed for wood. Important management goals, in

addition to timber production, include enhancement of wildlife, water, recreation, biological

diversity, and aesthetics. 

The goals of reserve management include conserving and protecting natural areas from

human-caused disturbances and may involve restoring the forest to some predetermined reference condition. In either case, financial return on investment or commodity goals do not apply.

Reserve management can be intrusive or nonintrusive. When the goal is to restore a natural

condition or process, treatments may be quite intrusive and intensive. Timber harvesting, logging or prescribed burning might be applied to retain early successional species, create desired

structural features, reduce the threat of insect and disease outbreaks, control exotic species, or

accelerate growth of large-diameter trees.

Many of the management guidelines for red pine that follow are framed around this principle

of a gradient of management goals including: 1) production management, 2) extensive management, and 3) reserve management. The reader is reminded that the value of different management approaches is driven by landowner objectives. We do not advocate one approach over

another, but simply present a range of options.
3

Ecological and Silvical Highlights of Red Pine

Before settlement, red pine made up an estimated one-third of the 22 million acres of pine forest in Minnesota, Wisconsin, and Michigan. The amount of red pine in the contemporary landscape—around one million acres—is greatly reduced from this total, due to uncontrolled 

timber harvesting, wild fire, and land conversion to agriculture and development. Today there

is a greater proportion of aspen on the landscape. 

On drier sites, red pine forests range from nearly pure stands to mixtures of jack pine, eastern

white pine, aspen, paper birch, and oaks. On moister sites, red pine is found growing with

eastern white pine, red maple, red oak, balsam fir, and white spruce. Red pine grows best on

well-drained sandy to loamy sand soils, but is most common on sandy soils having site indices

of 45 to 75 feet at 50 years of age. 

Red pine is a shade-intolerant, long-lived species characteristic of drier sites and soils.

Although individual trees can reach 400 years of age, most stands live no longer than 200

years. The species is best described as mid-successional. It often replaces early successional

species such as jack pine and aspen, and in turn is replaced by eastern white pine and 

hardwoods. 

Red pine is a fire-adapted species. Historically, natural stands with a significant red pine component were disturbed by frequent surface fires and less frequent crown fires. In combination,

these disturbances helped perpetuate the species by controlling competing understory vegetation, preparing mineral seedbeds, and opening the canopy to promote seedling establishment. 

Red pine flowers in the spring. Both male and female flowers are produced on the same tree.

Cones ripen the following summer, dispersing seeds for up to a year. Good seed crops occur

every 3 to 7 years. Timing seedbed preparation to good seed years is requisite for abundant

natural regeneration of red pine. 

Red pine has a variety of uses, including pulpwood, cabin logs, poles, and saw logs. Red pine

forests, both pure and mixed, provide habitat for a variety of plant and animal species. 
4

MANAGEMENT GOALS, OBJECTIVES, AND IMPLICATIONS

The following management action key (table 1) is based on the premise that stand-scale 

objectives fall largely within one or more of the three ownership goals: production management, extensive management, or reserve management. For each of these goals, the key guides

the user through applicable decisions and refers him or her to sections in the guide that

address details of particular actions. Where management objectives encompass more than one

goal, for example, production management within multi-species stands, users can integrate

information to address their specific needs. 

To use the management action key, start with the first pair of numbered statements and choose

the one that best describes your goal or situation. Follow this statement to a number, a recommendation, or a number and a recommendation. If a number is given, find the corresponding

pair of statements and continue the process until you reach a final recommendation. 

Red Pine Management Considerations

Table 1.—Management action keys for red pine management

Start Condition or Goal Go to or do

1. Site is typical for red pine in the locale 2.

See Ecological and Silvical Highlights of Red Pine, p. 3

1. Site is not typical for red pine 4. 

2. Reserve management objectives dominate Go to Key A

See Managing Stands in the Context of Ownership Goals, p. 2

2. Reserve management objectives do not dominate 3.

See Managing Stands in the Context of Ownership Goals, p. 2

3. Production management is the primary objective Go to Key B

See Managing Stands in the Context of Ownership Goals, p. 2

3. Extensive management is the primary objective Go to Key C

See Managing Stands in the Context of Ownership Goals, p. 2

4. Site is less productive (drier or wetter) than typical red pine site Consider establishing or converting to 

See Ecological and Silvical Highlights of Red Pine, p. 3 site-appropriate species

4. Site is more productive than typical red pine site Consider establishing or converting to

See Ecological and Silvical Highlights of Red Pine, p. 3; site-appropriate species or intensive 

Site Quality Assessment, p. 9. red pine production (Key B)

(Table 1 continued on next page)
5

Key A: Reserve Management

1. Red pine stand already established on site 2.

1. No red pine stand currently on site 5.

2. Stand is seedling size 3.

2. Stand is not seedling size 7.

3. Stand currently meets expectations for composition and structure Reassess at later date

Consider protection needs; see Damaging Agents, p. 29

3. Restoration needs exist in terms of structure or composition 4.

See Managing Red Pine Stands for Ecological Complexity, p. 23

4. Stocking of red pine is unacceptably low 5. Regenerate all or portions of site

4. Stocking of red pine is variable or stocking of other Fill plant and/or control competition; 

desirable species is inadequate or competition levels reassess at later date

are undesirably high

See Regenerating Red Pine, p. 13

5. No established stand on area 6. Consider all regeneration options in

light of Reserve Management goals

5. Established stand on area 6. Harvest in light of 

Consider conversion and legacy retention prescriptions; Reserve Management goals

see Managing Red Pine Stands for Ecological Complexity, p. 23

6. Good establishment conditions exist, free of undesirable competition Plant or seed; 

Consider regenerating multiple species; reassess at later date

see Regenerating Red Pine, p. 13 and Managing Red Pine

Stands for Ecological Complexity, p. 23

6. Inadequate establishment conditions exist Prepare site; plant or seed;

Consider regenerating multiple species; reassess at later date

see Regenerating Red Pine, p. 13 and Managing Red Pine 

Stands for Ecological Complexity, p. 23

7. Stand requires structural or compositional treatment in light of Thin, release, or underplant;

Reserve Management objectives reassess at later date

Consider variable density thinning, releasing co-occurring species; 

underplanting additional species; see Stand Density, p. 19; 

Managing Red Pine Stands for Ecological Complexity, p. 23; 

consider protection and maintenance needs (e.g., prescribed 

understory fire); see Damaging Agents, p. 29 

7. Stand condition (structure and composition) meets expectations Reassess at later date

Consider protection and maintenance needs (e.g., prescribed 

understory fire); see Damaging Agents, p. 29 

(Table 1 continued on next page)

Start Condition or Goal Go to or do

(Table 1 continued)
6

Key B: Production Management

1. Red pine stand already established on site 2.

1. No red pine stand currently on site 5.

2. Stand is seedling size 3.

2. Stand is not seedling size 9.

3. Stocking and competition levels are acceptable Reassess at later date

for production management 

See Regenerating Red Pine, p. 13 

3. Stocking and or competition levels are unacceptable 4.

4. Stocking is unacceptable 8. Replant

See Regenerating Red Pine, p. 13 

4. Stocking is variable and/or competition levels are high Fill plant or control competition; 

See Regenerating Red Pine, p. 13 reassess at later date

5. No merchantable stand on area 6.

5. Merchantable stand on area 8. Harvest and consider all

See Regenerating Red Pine, p. 13. regeneration options in light of 

Production Management goals

6. Will have merchantable stand in 20 years or less 7.

6. Will not have merchantable stand in 20 years 8.

7. Consider waiting until merchantable size Reassess at later date

7. Prepare site now according to Production Management goals 8.

8. Good establishment conditions exist, free of Plant; reassess at later date

excessive slash and competition

See Regenerating Red Pine, p. 13

8. Inadequate establishment conditions exist in the form of Prepare site; plant; 

excessive slash, herbaceous or shrub competition reassess at later date

See Regenerating Red Pine, p. 13

9. Stand is at rotation age for production management Harvest; go to 8.

See Rotation Age, p. 22

9. Stand is not at rotation age for production management 10.

10. Stand requires thinning, crop trees require pruning, or Thin, prune, or release;

competition control is needed reassess at later date

See Stand Density, p. 19; Pruning, p. 21;

Growth and Yield, p. 22; Damaging Agents, p. 29 

10. None of the above are required Reassess at later date

Start Condition or Goal Go to or do

(Table 1 continued)

(Table 1 continued on next page)
7

Key C: Extensive Management

1. Red pine stand already established on site 2.

1. No red pine stand currently on site 5.

2. Stand is seedling size 3.

2. Stand is not seedling size 9.

3. Red pine stocking, competition levels, and species composition Reassess at later date

are acceptable for extensive management

See Regenerating Red Pine, p. 13; Managing Red Pine Stands 

for Ecological Complexity, p. 23 

3. Red pine stocking, competition levels, or species composition 4.

are unacceptable for extensive management

4. Stocking of red pine is unacceptable 8. Regenerate site

See Regenerating Red Pine, p. 13 

4. Stocking of red pine is variable or stocking of other desirable species Spot-plant red pine or other species; 

is inadequate or competition levels are undesirably high control competition; 

See Regenerating Red Pine, p. 13 reassess at later date

5. No merchantable stand on area 6.

5. Merchantable stand on area 8. Harvest in light of 

Consider restoration opportunities; Extensive Management goals

consider legacy retention prescriptions; 

see Managing Red Pine Stands for Ecological Complexity, p. 23 

6. Will have merchantable stand in 20 years or less 7.

6. Will not have merchantable stand in 20 years or less 8.

7. Consider waiting until merchantable size before action Reassess at later date

to regenerate red pine 

7. Prepare site now according to Extensive Management goals; 8.

consider restoration opportunities and legacy 

retention prescriptions;

see Managing Red Pine Stands for Ecological Complexity, p. 23

8. Good establishment conditions exist, free of undesirable 

competition Plant or seed; reassess at later date

Consider regenerating multiple species;

see Regenerating Red Pine, p. 13; 

Managing Red Pine Stands for Ecological Complexity, p. 23

8. Inadequate establishment conditions exist Prepare site; plant or seed;

Consider regenerating multiple species; reassess at later date

see Regenerating Red Pine, p. 13; Managing Red Pine 

Stands for Ecological Complexity, p. 23

(Table 1 continued on next page)

Start Condition or Goal Go to or do

(Table 1 continued)
8

Key C: Extensive Management (continued)

9. Stand is at rotation age for extensive management objectives Harvest, regenerate; go to 8

Consider legacy retention prescriptions;

see Rotation Age, p. 22; Managing Red Pine Stands for 

Ecological Complexity, p. 23; Damaging Agents, p. 29

9. Stand is not at rotation age for extensive management 10.

10. Consider standard or variable density thinning, pruning, Thin, prune, release; 

release of co-occurring species, decadence creation, reassess at later date

underplanting tolerant species; 

see Stand Density, p. 19; Pruning, p. 21; 

Managing Red Pine Stands for Ecological Complexity, p. 23. 

10. None of the above are required or desired Reassess at later date

GENETIC CONSIDERATIONS IN RED PINE MANAGEMENT

Red pine is one of the most genetically uniform tree species. Nonetheless, small but significant

differences among families have been detected for traits such as height and volume. Differences

also exist among regions. For example, 11-year results from a replicated progeny test indicated

that although good stands could be found in all regions, the seed sources from the Lower

Peninsula of Michigan outperformed all other regions on eight of nine sites and ranked second

on the ninth site (Wright et al. 1972). Also, differences in chloroplast DNA exist across the

species’ range suggesting that the postglacial history of red pine is more complex than originally

thought (Walter and Epperson 2001). Collectively, this morphological and molecular data indicate that red pine has a complex evolutionary history and does possess genetic differentiation at

the regional and family levels.

Production Management

In production management, the overriding goal is to optimize the return on investment from the

growth and quality of wood products. As early as 1901, red pine was viewed as a potential plantation species. Historically interest has been focused on timber and fiber production. Despite this

interest, few organizations have taken steps to produce improved red pine seed or specified

improved red pine seedlings for their planting programs. Instead they have relied on seeds collected from native stands in the mistaken belief that improvements in growth were impossible or

inconsequential.

Improved red pine seed can be provided through the establishment of seedling seed orchards,

which are a relatively easy, cost-effective method for increasing the supply of genetically

improved seed. Many of these orchards, established between the early 1960s and late 1980s,

now produce operational levels of improved seed that are adapted to local growing conditions.

Estimates of volume gain for these improved seedlings vary but the selection method used has

an impact on the genetic diversity of the seed coming from these orchards (David et al. 2003).

Start Condition or Goal Go to or do

(Table 1 continued)
9

Extensive Management

With extensive management, natural regeneration is the primary method of restocking the

stand. Managers should take genetic considerations into account when choosing the leave trees

that will produce seed for natural regeneration. Guidelines for selecting leave trees are based

on research into heritability, which measures how much of a trait is controlled by genes as

opposed to the environment. The higher the heritability the easier it is for field personnel to

visually select trees with superior genes. In a native stand or population it is difficult to pick

superior trees for traits such as height, diameter, or volume, because these traits have low heritability. It is much easier to identify trees with better than average genes for stem form, branch

angle, and branch thickness, because these traits have medium to high levels of heritability. As

a general rule leave trees should be disease free, and have straight stems with medium to thin

branches that meet the trunk at a 90o angle. They should also be good self-pruners and have

crowns balanced in height and width. Trees with large diameter branches and those with

forked stems and irregular or misshapen crowns should be avoided.

Reserve Management

With reserve management, most trees will be retained, although some trees may be removed

to facilitate restoration goals. Typically, selection for specific traits will not drive decisions

about removal or retention. One caveat comes into play here: that of a minimum population

size necessary to maintain a viable population. Although the pollination dynamics in small

populations of forest trees is not well understood theoretical work has indicated that 50

breeding individuals are sufficient for maintaining existing genetic diversity in a population.

In red pine the required number of breeding individuals is expected to be lower than 50 for

two reasons. First, compared to other conifers red pine has lower levels of genetic variation,

so fewer individuals would be required to maintain existing genetic diversity. Secondly, red

pine can tolerate elevated levels of inbreeding with no loss of seed set or germination, (albeit

with a loss of some height growth). Managers should bear in mind that the number of

breeding individuals is not the same as the total number of individuals. Generally, the number of breeding individuals is lower because immature or suppressed trees may not produce

pollen or cones, and other individuals may produce cones infrequently, or be asynchronous

with the majority of the population.

ESTABLISHMENT CONSIDERATIONS 

Site Quality Assessment

Managers and landowners often want to estimate potential growth before establishing a red

pine stand. Understanding site quality and choosing a proper site can optimize tree growth

and survival, and minimize the risk of insect and disease infestations. Site quality data can also

help managers project growth and yield in established stands. This section provides a summary

of existing site quality work and how it may be used to select sites for plantation establishment

and identify sites for intensive management.
10

Several methods are currently used to assess site quality in the Lake States and Northeast,

including site index curves, soil-site approaches, and vegetative and biophysical approaches.

Depending on the size of their holdings, landowners may be limited in the range of site qualities available for red pine. In such instances, relative measures of site quality may be useful.

For example, if landowners’ goals include production, extensive, and reserve management,

they may choose higher quality sites for timber production and lower quality sites where red

pine occurs naturally for reserve management. On the other hand, they may wish to practice

both timber management and reserve management on high-quality sites and extensive management on the remainder of their land holdings. In either case, an assessment of site quality

would be important.

Site Index

Site index is the most commonly used method of assessing site quality in North America

and is defined as the height of a tree at a base or index age, usually 50 years. Trees measured

to determine site index should be over 30 years old and be in a dominant or codominant

canopy position.

Site index curves for red pine that have withstood the test of time (Benzie 1977) are provided

in figure 1. Carmean et al. (1989) conducted a review of site index curves for all species in

North America in the 1980s. Seven additional site index curves for red pine are included in

appendix A.

75

65

55

45

140

120

100

80

60

40

20

20 40 60 80 100 120 140 160 Site Index

Age (years)

Total height (feet)

Figure 1.—

Red pine site index

curves; based on

the equation:

height = site index

(1.956 – 2.1757 

e–0.01644(age))

(Lundgren and

Dolid 1970).
11

Growth Intercept

It is not always possible to determine site index directly. Records may not exist for a given

stand before the establishment of a plantation, or the plantation may be considerably younger

than the index age. Site index can be estimated in such cases by using the growth intercept

method, which utilizes a designated period of early height growth as an indicator of site quality. To eliminate potential error associated with slow and erratic height growth, managers

should measure internode length above breast height. The primary disadvantage of the growth

intercept method is that early height growth patterns may not accurately reflect later height

growth patterns. Tables 2 and 3 provide estimates of site quality for red pine based on annual

internode growth above breast height.

Red pine plantations are often established on sites occupied by other species. Or, a landowner

may wish to convert another type of forest type to red pine. Site index for red pine can be estimated from other trees growing on such sites provided the site index for these trees can be

determined (table 4).

Table 2.—Estimates of site index for red pine trees greater than 15 years old (based

on the equation SI = 36.9 + 3.356GI – 192.474GI-2, where, SI = site index and GI =

length of 5 internodes above 8 feet). (Alban 1972a)

Length of 5 internodes above 8 feet Site index

(feet) (feet)

4 38

5 46

6 52

7 56

8 61

9 65

10 68

11 72

12 76

Table 3.—Site index estimates based on average annual height growth above

breast height

Average annual height growth above bh Site index

(inches) (feet)

10 45

13 55

17 65

24 75
12

Soil-Site Approaches

Soil-site studies are undertaken to determine a relationship between site index and edaphic

(soil-related) and other variables describing a particular site (e.g., aspect, elevation). Although

soil-site studies typically have only regional applicability, they can be generalized across regions

if studies from different regions have similar results. Results of eight soil-site studies (Hicock et

al. 1931; Van Eck and Whiteside 1958; Wilde et al. 1965; Hannah 1971; Alban 1972b, 1974,

1976; Brown and Duncan 1990) across the range of red pine are summarized below.

Site index is positively related to improved soil drainage, a sandy loam soil texture, rooting

depth, and thickness of the A and B soil horizons. Site index is also positively correlated with

the presence of finer textured soil bands or layers totaling a thickness of at least 3 to 6 inches

within 8 to 15 feet of the soil surface. Site index is negatively correlated to the percentage of

gravel or rocks in the top 10 inches of soil (table 5). The percentage of soil organic matter, or

soil carbon, has been found to affect site index both positively and negatively. Aspect and percent slope have relatively small impact on site index, although higher site indices tend to be

associated with lower slope positions. Higher concentrations of soil N and P are also related to

higher site indices.

Table 4.—Site index (in feet) conversions to red pine from jack pine, white pine,

white spruce, and aspen site indices

Red pine Jack pine White pine White spruce Aspen

45 50 45 35 40

55 60 55 50 60

65 70 65 65 80

75 80 75 80 100

Table 5.—Estimated site index for red pine plantations in the Lake States on 

well-drained sand to sandy loam soils1

Depth of A plus B horizons (inches)

Gravel or rocks in top 10 inches 5 10 20 30 40 50

Percent by weight Site Index (feet)

0 55 57 60 63 67 70

10 52 54 57 60 63 67

20 49 51 54 57 60 63

30 46 48 51 54 57 60

40 43 45 48 51 54 57

50 40 41 44 48 51 54

1

Add 5 feet to site index on soils with bands or layers of finer textured material within 8 feet of the surface that improve water

relations; subtract 5 feet from site index for natural stands (adapted for the Lake States from Alban (1976).
13

Other Considerations

It is important to consider that site index predicts the height of dominant or codominant trees

in a stand at a given base age. Factors in addition to site index may be important in comparisons of productivity. For example, a side-by-side comparison of 40-year-old red pine and jack

pine stands growing on the same soil showed that red pine had 55 percent more volume than

jack pine. The red pine had produced 225 ft2 per acre of basal area in 40 years, compared with

152 ft2 per acre of basal area for jack pine. Red pine has an ability to grow at higher densities

than other species.

REGENERATING RED PINE

This section provides an overview of site preparation, planting, and release treatments for red

pine—practices that can help managers meet a wide range of objectives. Artificial regeneration

is emphasized because relatively little work has been conducted on the natural regeneration of

red pine and few managers have experience with the practice. Indeed, managers often favor

direct seeding over plantation establishment. Limited information on red pine natural regeneration does suggest that: 1) natural regeneration is best on shaded mineral soil, 2) shading

down to 25 percent of full light does not affect early survival or height growth, 3) mechanical

site preparation has greater efficacy in reducing competing vegetation than prescribed burning,

and 4) insects are a major cause of first-season mortality, especially in areas having higher

amounts of light. 

Site Preparation

Effective site preparation helps improve the growing conditions for regeneration. Good site

preparation should minimize competition for light, water, and nutrients without causing soil

loss or damage. In the context of planting, the primary goals of site preparation are to reduce

competing vegetation and create conditions conducive to planting. This may, at times, be

achieved simply through full-tree harvesting. Spot site preparation practices may also prove

adequate, particularly for fill planting.

Mechanical, chemical, and prescribed burning treatments may be used for site preparation.

Typical site preparation practices in the Lake States include disk trenching, roller chopping,

scalping, and prescribed burning. Former practices that were once common include Brakee

plowing and brush raking. Generally, the higher the site quality the greater the need to control

woody and nonwoody vegetation to favor red pine establishment.

Herbicides work well to control competition and release planted red pine seedlings. A variety

of chemicals may be used, depending on site quality, soil conditions, and competing vegetation. All herbicides must be applied by a State-certified or licensed applicator. The herbicide

label includes directions, requirements for protective equipment, application site restrictions,

crop species recommendations, and weed species controlled. The herbicide label instructions

must be adhered to. 
14

Prescribed burning is most effective for site preparation soon after harvesting when slash provides fuel. Conifer slash can be burned almost immediately after harvest, but hardwood slash

needs several weeks to cure. In mature red pine stands, one or more summer fires can be used

to eliminate shrubs and reduce duff levels before harvesting. There may be concerns about

charring standing timber. Burning plans should be approved and permits obtained as required.

Planting

Planting of bare root red pine or containerized seedlings should be done in the spring. Trees

should be planted at least as deep as they grew in the nursery. On drier sites, planting slightly

deeper may be beneficial, but planting too deep increases risk of injury by root collar weevils.

Larger bare root seedlings or transplant stock should be used on more difficult sites, or when

higher probability of establishment success (but greater cost) is desired. The cost of producing

containerized seedlings has been reduced in recent years and their usage has expanded.

Containerized seedlings, which are preferred on sites having shallow soils, can extend the

planting season into early summer. 

The time required for planted red pine to reach pole size (5 inches diameter) will vary from 15

to 30 or more years depending on spacing and to a lesser extent on site quality. Closer spacings will require precommercial thinning of saplings (2-5 inches average diameter) to provide a

recommended 50 square feet of growing space for each crop tree; wider spacings may need an

extra release or two to control grass, shrub, and hardwood competition.

Spacing recommendations depend on many factors, including planting conditions, management objectives, and the desired final product. Planting 400 trees per acre (slightly more than

a 10 x 10 foot spacing) will be less costly than closer spacing, and commercial thinnings can

be made by the time trees need more growing space. Crop trees will grow rapidly, and crown

closure will not shade out ground vegetation for about 20 years. Planting 800 trees per acre (a

little less than 8 x 8 foot spacing) will allow greater flexibility in selecting crop trees and controlling early stand development. Crop trees will have less taper and smaller branches, and the

stand will have more total volume in smaller diameter trees.

Trees should be planted at spacings of up to 10 x 10 feet if all or most of the planted trees have

a good chance of surviving, precommercial thinnings are not likely, and favoring ground layer

plant communities is an objective. Most production-oriented plantations are established at

spacings of 6 x 8 feet and 6 x 10 feet. Machine planting costs can be reduced by using wider

rows and closer spacing of trees in a row, but access for future management operations must

also be considered at the time of stand establishment. 

Patterns other than uniformly spaced row plantings should be considered for some extensive management and restoration applications. While planting remains a cost effective way of ensuring adequate red pine regeneration, some objectives require planted stands to look less like plantations and

more like natural stands. Variable row widths and spacings or spiral planting schemes can be considered. Planting schemes can also be designed to accommodate future thinnings and harvest. For

example, a rectangular 8 x 12 foot spacing would facilitate the use of modern harvesting equipment.
15

Seeding

Natural seeding during good seed years can successfully establish seedlings on prepared

seedbeds, such as those treated with summer prescribed burning under a mature stand.

Scarifying the soil may also be successful if shrubs are not present. 

Direct seeding is not widely employed, but has been used successfully on well-prepared sites

provided adequate soil moisture is present during the first several months after germination.

Seed should be coated with bird and rodent repellants and sown at approximately 15,000 viable

seeds per acre (about 5 ounces) early in spring to take advantage of moist soil conditions.

Somewhat better results have been obtained by covering red pine seed with 0.25 inches of soil

(it is easier to cover the seed when sowing 5 to 10 seeds in prepared spots). However, it may be

easier to broadcast more seed on the surface than to use less seed and cover it. Direct seeding in

general has not been successful because of inadequate site preparation, inadequate moisture, or

loss of seeds to birds or rodents. There is also less control of stocking following direct seeding.

Regenerating Species Mixtures

Production managers may wish to regenerate red pine exclusively and prevent establishment of

other tree species during early stand development. In contrast, extensive and reserve management may dictate regeneration of other tree species along with red pine (see Managing Red

Pine Stands for Ecological Complexity). Associated species may develop from advance regeneration in the new stand through vegetative means or from seed during early stand development.

Alternatively, other species may be planted along with red pine. 

Releasing Regeneration

Release of red pine seedlings from shrubs and other low competitors may be needed after the

third growing season. The most practical tool for release is chemical control with broadcast

foliar herbicides. For best results, spraying should occur after pine leader growth is complete

and the terminal bud is set, around mid-July, and be completed before the end of the growing

season to avoid damage to red pine seedlings. 

At the time of this writing, herbicide use is restricted on national forests in the Lake States and

Northeast to nonforestry applications. Moreover, some landowners may choose not to use herbicides for a variety of reasons. In these cases, mechanical release is the only alternative. Cutting

or mowing is labor intensive and results in resprouting of undesired vegetation because the root

systems remain intact. It must be reapplied at 2- to 3-year intervals. Additionally, mechanical

release does little to provide adequate growing space for newly planted trees on sites with abundant herbaceous competition.

A Decision Key Specific to Red Pine Regeneration

The following key (table 6) to planting and vegetation management is based on more than 30

years of combined field experience in Itasca, St. Louis, and Cook Counties in northern

Minnesota. In other regions, managers may wish to make adjustments based on field experience. Nonetheless, it serves as a useful guide to managing red pine for a variety of objectives. 
Consider the following when using this key:

1. Stockability refers to the stocking potential of a site in terms of suitable planting area. For

example, shallow soils, exposed bedrock, and small wetlands—all common in the northern

Lake States—preclude high levels of stocking. 

2. The guidelines listed are intended to maximize survival of planted stock. High- intensity or

production management indicates a primary goal of maximum fiber and wood production

in a plantation setting. Low-intensity or extensive management implies a combination of

goals, including mixed-species management.

3. Definitions:

Delay—delay treatment in the next growing season.

Reassess—re-evaluate during the next growing season.

Release—remove undesirable species.

Weed—remove competition of all sizes.

Liberate—remove individuals overtopping desirable species.

Fill plant—add to existing stocking by interplanting.

Replant—ignore existing seedlings and begin stand over. 

16

Table 6.—A decision key specific to red pine regeneration

Start Condition or Goal Go to or do

Production Management

1. Stockability high (potential > 500-750 TPA) 2.

1. Stockability low (potential < 500-750 TPA) 16.

2. Age < 2 yrs in the ground 3.

2. Age > 2 yrs in the ground 10.

3. High fertility site 4.

3. Low fertility site 8.

4. Survival > 65-75% 5.

4. Survival < 65-75% Release and fill plant with red pine

5. Competition is predominantly herbaceous 6.

5. Competition is predominantly woody 7.

6. 30% trees overtopped Release

6. < 20-30% trees overtopped Reassess at 5 years

7. 25% trees overtopped Release

7. < 10-25% trees overtopped Reassess at 5 years

8. Survival > 65-80% 9.

8. Survival < 65-80% Release and fill plant with red pine

9. > 20-25% trees overtopped from herbaceous and woody Release for major competition type

(Table 6 continued on next page)
17

9. < 20-25% of trees overtopped from herbaceous and woody Delay release and reassess

10. Survival > 60-70% 11.

10. Survival < 60-70% Site preparation and replant

11. Competition is predominantly herbaceous 12.

11. Competition is predominantly woody 13.

12. > 20-40% overtopped Release

12. < 20-40% overtopped Reassess at 5 years

13. Woody species desirable in final stand 14.

13. Woody species not desirable in final stand 15.

14. > 10-25% overtopped Release

14. < 10-25% overtopped Reassess in 5 years

15. > 10-20% overtopped Release

15. < 10-20% overtopped Reassess in 2 years

16. Age < 2 years 17.

16. Age > 2 years 25.

17. High fertility site 18.

17. Low fertility site 22.

18. Survival > 50-70% 19.

18. Survival < 50-70% Release and fill plant with red pine

19. Competition is predominantly herbaceous 20.

19. Competition is predominantly woody 21.

20. > 20-30% trees overtopped Release

20. < 20-30% trees overtopped Reassess in 5 years

21. > 10-25% trees overtopped Release

21. < 10-25% trees overtopped Reassess in 2 years

22. Survival > 50-70% 23.

22. Survival < 50-70% 24.

23. Grass and undesirable shrubs > 20-30% Release

23. Grass and undesirable shrubs < 20-30% Reassess in 5 years

24. Red pine and other desirable woody tree species increases Consider mixed-species management

density to 600 TPA

24. Undesirable woody competition Release and interplant (consider inter

planting with alternate species)

25. Survival > 40-60% 26.

25. Survival < 40-60% 27.

(Table 6 continued on next page)

Start Condition or Goal Go to or do

(Table 6 continued)
18

26. Grass and shrub competition overtop > 10-30% of trees Release

26. Grass and shrub competition overtop < 10-30% of trees Reassess in 5 years

27. Planted trees plus other desirable tree species Liberate planted trees

density > 350-500 TPA

27. Insufficient volunteers to reach 350-500 total TPA Site prep and replant red pine

Extensive Management

1. Age < 3 years 2.

1. Age > 3 years 11.

2. Survival > 50-65% 3.

2. Survival < 50-65% 8.

3. Competition is predominantly herbaceous 4.

3. Competition is predominantly woody 5.

4. > 20-35% trees overtopped Spot or broadcast release

4. < 20-35% trees overtopped Assess shrub competition and monitor

5. Woody competition is predominantly desirable tree species 6.

5. Woody competition is shrubs or undesirable species 7.

6. > 25-35% trees overtopped Release or liberate by mechanical means

6. < 25-35% trees overtopped Monitor

7. > 15-25% trees overtopped Release or liberate by mechanical means

7. < 15% trees overtopped Monitor

8. Other desirable tree species > 1,000 stems per acre 9.

8. Other desirable tree species < 500 stems per acre 10.

9. > 25-50% planted trees overtopped by competition Spot release

9. < 25-50% planted trees overtopped Monitor

10. > 15-25% planted trees overtopped Patch or row scarify and fill plant (consider

shade-tolerant species)

10. < 15-25% planted trees overtopped Release or liberate by mechanical means

11. Woody competition is predominantly desirable species 12.

11. Woody competition is predominantly undesirable species 13.

12. > 15-30% trees overtopped Release 

12. < 15-30% trees overtopped Monitor

13. Survival > 35-65% 14.

13. Survival < 15-35 % Consider site preparation and replant or fill plant

14. > 15-30% trees overtopped Release

14. < 15-30% trees overtopped Monitor

Start Condition or Goal Go to or do

(Table 6 continued)
19

MANAGING ESTABLISHED STANDS

Stand Density

Foresters manage stands to meet a variety of landowner objectives. In cases where timber production is the primary goal, management often focuses on maximizing financial return. This

usually means encouraging growth on desirable trees while removing and utilizing the less vigorous ones. Density control is the primary means by which this is accomplished.

Stocking level and uniformity are important aspects of stand density in even-aged stands. As

stocking level decreases towards a minimum, uniform distribution of trees increases in importance. Benzie (1977) calculated the minimum stocking in basal area and trees for perfectly uniform stands of various average stand diameters from the maximum amount of growing space

trees of each diameter could use (fig. 2). Minimum stocking for stands averaging 5 inches in

diameter is about 400 trees and 60 ft2

per acre-1. In stands averaging 15 inches in diameter,

minimum stocking is about 80 trees and 100 ft2 per acre-1. 

The stocking chart (fig. 2) suggests the upper limit of stocking, as determined by the A-line,

stands averaging 5 inches in diameter is about 1,100 trees and 150 ft2 per acre-1 of basal area.

For stands averaging 15 inches in diameter, the recommended upper limit of stocking is 175

trees and 215 ft2 per acre-1 of basal area. Contemporary management entails lower planting

densities, planting equipment considerations, and access for precommercial thinnings.

Seedling and sapling stands (less than 5 inches average diameter) should have between 400

and 900 trees per acre. Fewer than 400 trees will not provide minimum recommended stocking by the time the stand reaches poletimber size, and more than 900 trees will exceed the

upper limit of recommended stocking before the trees reach poletimber size and can be

thinned commercially.

Stocking Chart

Basal area per acre

Trees Per Acre

Figure 2.—

Stocking chart for

red pine (Benzie

1977).
20

Stand density guides for uneven-aged red pine stands have not been formalized. However,

uneven-aged management of red pine is not uncommon. Therefore, seedlings generally need 

to outnumber saplings, saplings need to outnumber poles, and poles need to outnumber sawtimber trees. Losses in the smaller size classes are expected and considerable effort will be

needed to ensure survival and growth of enough trees in each class to replace those harvested,

lost, or recruited into the next size class. Regeneration in uneven-aged red pine stands must 

be monitored for Diplodia and Sirococcus shoot blights (see page 42).

Precommercial Thinning

Precommercial thinning may be needed in young stands to meet management objectives.

For example, in a naturally regenerated stand of small saplings (less than 2 inches average

diameter) having more than 2,000 trees per acre, a minimum of 100 potential crop trees per

acre should be given a minimum growing space of 25 ft2 per tree. Densely stocked sapling

stands (2 to 5 inches average diameter) with a basal area of 160 ft2 per acre-1 or more should

be precommercially thinned. Crop trees in sapling stands should be given about 50 ft2 of

growing space per tree to maintain good diameter growth.

Commercial Thinning 

One of the most important ways stand composition and development can be controlled is by

periodic commercial thinnings. Stands should be thinned before they exceed the recommended upper limit of stocking for managed stands (see below). For production management, a

uniform distribution of high-quality trees with at least the minimum recommended stocking

for the average stand diameter should be left, but not over half—and preferably less—of the

basal area should be removed in any one thinning. Stands managed near the minimum recommended stocking will have the most rapid diameter growth. As a general guide, pole stands (5

to 9 inches average diameter) should be thinned when basal area reaches 140 ft2 or more per

acre, leaving about 90-110 ft2 per acre-1. 

Stocking charts and density management diagrams (DMDs) are popular tools for developing 

thinning prescriptions for even-aged stands. Their popularity stems from their ability to easily

incorporate the ecological principle of self-thinning, or competition-induced mortality, which

provides the stimulus for thinning. Managers should strive to prevent stands from reaching the

density where self-thinning can occur. In the stocking chart (fig. 2), self-thinning begins at the Aline. Basal area is represented by the “Y” axis and trees per acre are represented by the “X” axis.

Average stand diameter at breast height is represented by the lines radiating out from the origin of

the two axes. Red pine stands are overstocked above the A line—too much basal area and too

many trees per acre. The stand is understocked below the B line—too few trees of any size. 

Stocking charts and DMDs are similar management tools, but they use a different scale of

measurement (DMDs use a logarithmic scale). A density management diagram for red pine and

instructions for its use can be found at:

http://www.cnr.umn.edu/FR/publications/staffpapers/Staffpaper158.pdf.
21

Thinning will not usually result in an increase in stand volume at the end of the rotation.

Rather, it will allow individual trees to grow larger, increasing the relative rate of stand growth.

Thinned volume plus volume at the end of the rotation (total yield) may or may not be higher

than the total volume of an unthinned stand. Thinning, however, serves to capture volume otherwise lost to mortality. Thus, total volume removed over the life of a stand may be greater with

thinning. Site quality, thinning intensity, and stand age at thinning all affect volume removed

during thinning and stand volume at the end of a rotation. Residual trees should have a live

crown ratio of 30 percent or greater to receive the maximum potential growth response from

thinning. Many organizations emphasize a 40 percent live crown ratio. Depending on stand age,

trees with shorter live crown ratios may have a minimal growth response from thinning. Red

pine crowns develop upward and outward, never downward. Thus, if a stand is near its 

maximum potential height and has a 10 percent live crown ratio, very little growth response to

thinning can be expected. For red pine, post-thinning stand density has a greater impact on 

post-thinning stand growth (Gilmore et al. 2005) than the thinning method used (Smith 2003).

For production and extensive management objectives, sawtimber trees should be thinned periodically to maintain uniform growth rates on the crop trees. For extensive management in

mixed-species stands, red pine might be favored as crop trees at each thinning. However, other

species should be left to achieve biodiversity goals, meet habitat requirements, and expand the

species and type of timber products.

Prescribed Surface Fires

Prior to effective fire suppression, forests dominated by red pine periodically burned.

Infrequent, high-intensity fires that killed overstory trees opened the canopy, exposed mineral

seedbeds, facilitated regeneration, and created complex stands (see Managing Red Pine Stands

for Ecological Complexity 23 p.). More frequent, low-intensity surface fires helped to thin

dense stands and suppressed woody shrubs, including hazel. 

Prescribed surface fire in mature red pine stands can be an effective management tool for eliminating shrub competition, reducing thick duff layers, and preparing mineral seedbeds. Summer

fires, conducted over several growing seasons, are most effective at controlling dense shrub

competition and exposing mineral soil. This may be done before harvesting to prepare

seedbeds, unless charred bark on harvested trees poses a problem. Burning plans should be

approved and permits obtained as required.

Pruning

Production managers may use pruning to increase the value of red pine sawtimber by promoting growth of clear, knot-free wood in the first log of the tree. Managers must generally balance

the cost of producing high-value red pine logs containing clear wood with the costs of pruning.

Pruning in concert with thinning will reduce costs and help stimulate diameter growth.

The simplest and least expensive way to prune red pine in plantations is to plant at high densities and allow trees to self-prune. Higher plantation densities also encourage straight boles with
22

minimal taper. The natural process of pruning usually occurs as crowns close and lower branches

are shaded and fall off. Artificial pruning accelerates this process. The importance of pruning has

taken on greater importance with the increased use of “flitch” technology, a process in which

veneer is acquired from slicing very thin boards. It generally takes about 60 years (depending on

site quality, timing of pruning, and adequate thinning) to recoup the cost of pruning.

The use of proper technique is critical when pruning. Done improperly, pruning is a waste of

resources and can injure trees. There are a number of things to consider when pruning red

pine. Season is important; red pine pruning should be done in late fall to early spring, otherwise the bark is loose and can easily be stripped away from the stem by the weight of the

branch or saw. An adequate live crown can be maintained by keeping at least the upper twothirds of the live crown and removing only dead branches in the upper half of the tree. All

dead branches should be removed. Branches should be pruned flush with the end of the

branch collar so no stub remains (stubs can be entry sites for insect and disease infestations).

Only the largest diameter (dominant and codominant) trees with the best form should be

pruned because these trees have the greatest potential for return on investment. Pruning

should begin when trees reach a d.b.h. of 4 to 6 inches, and those with numerous branches

greater than 2 inches in diameter should be avoided.

Pruning may also be important in extensive management when objectives include production

of large quantities of trees with high-quality, knot-free timber. Moreover, pruning promotes

development of clear boles, which can be characteristic of old-growth conditions. Because

spacing in stands managed less intensively is typically wider than that in uniform plantations,

pruning may be required to remove lower branches on potentially high-value trees. 

In mixed-species stands, we recommend pruning if the stand is dominated by the desired

species (more than 60 percent of the trees). However, look for the possibility of an exchange of

dominance whereby unpruned trees overtake and reduce the growth of pruned trees in the

years immediately following pruning. In such cases, pruning all stems in the stand may be the

best course of action. 

Growth and Yield

Growth and yield equations have been refined over the years, but for the most part “modern”

equations do not differ greatly from volume tables published in the early 1900s. Stand volume

and individual tree prediction equations are provided in appendix B (table B2). Basal area

growth and yield tables from Benzie (1977) and derived from the works of Buckman (1962)

are presented in tables B2 through B8 in appendix B.

Rotation Age

Many factors determine rotation age, including site quality, desired product, stocking, and

management intensity. Generally, for production management purposes, the rotation age for

red pine is between 60 to 90 years, as defined by culmination of mean annual volume growth

increment. However, red pine is a long-lived species, providing opportunities to grow and
23

manage stands for up to 200 years and individual trees to even greater ages. In fact, rotations

exceeding 100 to 150 years have become more common on public lands and when managing

for large-diameter sawtimber. Periodic thinning extends economic rotation age by delaying culmination of mean annual increment. Rotation ages based on maximum mean annual boardfoot growth at different levels of basal area (after periodic thinning) are provided in table C1 of

appendix C. 

For reserve and extensive management, declining growth rates in older stands are not a primary

concern. Rather, the ecological contributions of old trees and stands are of primary interest.

Consequently, the shape of the mean annual increment curve and the influence of thinning on

growth may be less important to these landowners. 

MANAGING RED PINE STANDS FOR ECOLOGICAL COMPLEXITY

Ecological complexity in forest stands takes many forms—for example, species diversity, a wide

range of tree ages and sizes, multiple age cohorts, snags and dead logs on the ground, cavity

trees, wolf trees, tip-up pits and mounds, characteristic understory plant communities, and

varying forest floor conditions and soil patterns. Complex stands also vary in structure and

composition spatially, compared with simplified stands that are often uniform throughout. The

sustainability of native species (one aspect of biological diversity) often depends on the availability of structures and on the heterogeneity that exists in complex forest stands. 

Forest managers have little experience with managing red pine stands for complex stand conditions. There are no quantitative guidelines for doing so. However, such complexity was the

rule, not the exception before European-settlement. For example, evidence in the Lake States

indicates that red pine stands often included several other species in moderate abundance

including eastern white pine, jack pine, paper birch, aspen, oaks, and maples. Moreover, older

pine stands dominated the landscape, with up to 30 percent of them greater than 120 years

old. A reference stand exhibiting these characteristics exists in the “Lost Forty” in northern

Minnesota. Also, the age range of red pine in such stands sometimes spanned 100 years.

Historical photographs of red pine stands show the presence of snags, multiple species, and

several age cohorts; stand density, tree size, and tree condition vary, as do the distribution of

regeneration in the understory.

This is not to say that all presettlement red pine stands were highly complex; indeed, a range

of variation likely existed. Some stands dominated by red pine no doubt were largely singleaged, but even they were more complex than most managed stands in the contemporary landscape (e.g., they contained some snags and trees of other species). Today’s managed red pine

stands, by comparison, tend to be highly simplified in composition, age structure, density of

snags, logs, etc. It is also worth noting that stand complexity is not strictly a feature of old

stands. Even young stands regenerating after natural disturbances contain some larger, residual

trees, as well as abundant snags and logs on the ground and patches of undisturbed understory

vegetation and forest floor (fig. 3). 
24

INCORPORATING ECOLOGICAL COMPLEXITY INTO RED PINE

MANAGEMENT

Although managing red pine stands for ecological complexity is usually not a goal of production management, it can certainly be an issue in ecological reserves and also in extensive 

management. In addition to the general tools and approaches for red pine management outlined in this guide, the following basic principles should be considered when designing an

approach to sustain or restore ecological complexity: 

1) Incorporate biological legacies into regeneration harvest prescriptions.

2) Incorporate natural stand development processes into intermediate treatments.

3) Allow appropriate recovery periods between regeneration harvests.

Incorporate Biological Legacies into Harvesting Prescriptions

Biological legacies.—Biological legacies are the organisms, structures, and biologically created

patterns that persist from the predisturbance forest and influence development in the postdisturbance stand (table 7). Structural legacies include large, healthy, live trees, decadent trees,

snags, and logs and other coarse woody debris on the forest floor. Compositional legacies

include the organisms that survive a disturbance—trees, of course, but also nonarboreal plants,

fungi, and animals. Legacy patterns include the spatial distribution of remnant patches of

undisturbed understory vegetation, forest floor, and mineral soil. 

Simple

Complex

Figure 3.—

Simple versus ecologically complex

young red pine

stands; complex

stands may include

large residual trees

from the previous

stand, including

species other than

red pine, snags, and

dead logs on the

ground.
Modifying traditional regeneration harvests.—Traditional clearcut regeneration prescriptions

should be modified to include retention of large (healthy) red pine trees (and other species if

they are present), decadent trees, snags, and downed logs in a variety of sizes, including large

stems. Special consideration should be given to actual or potential cavity trees, mast trees, and

nest trees. Natural regeneration should be protected and promoted whenever possible, along

with planting or direct seeding. 

Red pine shoot blight.—If red pine shoot blight is a concern (see Damaging Agents, p. 29),

consider regenerating primarily white and jack pine after an initial regeneration harvest (or red

pine in areas where no evidence of shoot blight exists). Reducing losses from shoot blight while

retaining significant numbers of overstory red pine may mean retaining overstory red pine 

during an initial regeneration harvest, then planting or seeding other species (primarily white

and/or jack pine). Then, at the end of the next rotation, primarily mature white and jack pine

can be retained during a regeneration harvest, followed by planting or seeding of red pine. 

Retaining structure.—Determining the number and distribution of live trees, snags, logs, 

and other structural elements will depend on management objectives and desired future conditions. For instance, retention of low numbers of residual red pine (e.g., 20-30 ft2

/acre), followed

by regeneration, will result in largely single age-cohort stands containing scattered older trees.

In contrast, retention of 60-80 ft2 per acre of residual red pine at an initial harvest will result in

the development of two-age cohort stands and potentially multi-cohort stands if this level of

retention is repeated at future harvests. Leaving even small amounts of residual trees may result

in an overall reduction in growth of regeneration, but the continued growth of the residual

trees may well compensate for growth loss in the new cohort. Some ecological objectives 

are best achieved by dispersing trees, snags, and other structures throughout the stand, while 

others are best served by leaving patches of legacy trees (fig. 4, table 8). Best results may 

be obtained by alternating between patch and dispersed cutting across the harvest unit.

Retaining some large aggregates of live trees is also a good way to protect understory plant

25

Table 7.—Categories of biological legacies with some examples of types

Legacy category Examples

Organisms Mature, healthy live trees; declining trees

Tree reproduction

Seed banks

Shrub, herb, bryophyte species

Mature and immature animals

Organic matter Fine litter, particulate material

Organically derived structures Standing dead trees

Downed trees, coarse woody debris

Root wads and pits from uprooted trees

Organically derived patterns Soil chemical, physical, microbial properties

Forest understory composition and distribution
26

communities and forest floor environments. It may be best to adapt species regeneration to

residual overstory conditions—for example, favoring white pine under dispersed retention and

red or jack pine in openings. 

Incorporate Natural Stand Development Processes into Intermediate

Treatments 

Intermediate stand treatments such as thinning and pruning mimic the natural processes of

tree mortality and decline. In application, traditional thinning and pruning regimes create spatially uniform stands. Ecological complexity can be increased in established red pine stands by

modifying traditional intermediate treatments and adding nontraditional approaches like

“decadence creation”. In addition to “decadence creation”, specific treatments include variable

density thinning, maintaining or improving species diversity, and prescribed burning.

Figure 4.—Differing

spatial patterns of

red pine retention

after a regeneration

harvest. 

Uncut Stand Dispersed Retention Aggregate Retention

Table 8.—Effects of live tree retention pattern on red pine ecosystem 

characteristics

Characteristic Dispersed Aggregate

Regeneration growth (intolerant species) Lower Higher 

(between aggregates)

Regeneration growth (tolerant species) Higher Lower 

(outcompeted 

between aggregates)

Hazel production Higher Lower

Blueberry production Lower Higher

Logging efficiency Lower Higher

Residual tree damage Higher Lower

Campground quality Lower Higher

Fuels distribution Uniform Aggregate

Tree form and geometry Uniform Variable
27

Variable density thinning.—In traditional applications, stands are thinned uniformly to provide crop trees with equal access to moisture, nutrients, and light. In contrast, most unmanaged forests have varying stand density and a wider range of tree growth rates and sizes. In

such stands, mortality from competition, along with wind, lightning, insects, or fire can cause

mortality during stand development. To emulate this natural variation, managers can apply 

different degrees of thinning throughout the stand—i.e., some areas can be thinned heavily,

some moderately, and some left unthinned (fig. 5). This will result in variable stand density

and greater structural diversity.

Decadence creation.—Consider deliberate felling of live trees to increase the abundance and

types of dead logs on the ground. Also, consider girdling (or killing in some other way) living

trees to create snags. A range of tree sizes should be considered, including large diameter red

pine individuals. 

Improving species diversity.—Leaving some large gaps during thinning should help promote

less shade-tolerant tree, shrub, and herbaceous species. These species should be encouraged

for their contributions to ecological complexity and native plant diversity. Thinning should not

preferentially remove non-target tree species, that is, species other than red pine. In particular,

noncommercial species should be retained for their contributions to ecological complexity and

biological diversity. Finally, consider underplanting tolerant species, where seed sources or

advance regeneration for these are lacking.

Prescribed burning.—As mentioned earlier, surface fires periodically swept through red pine

forests, particularly on drier sites. Reintroducing surface fires will help maintain (or restore)

understory conditions that reflect those existing prior to effective fire suppression. Fires should

be allowed to burn naturally across the stand—that is, without making an effort to ensure that

the stand burns evenly. Surface fires will improve ecological diversity through fire scarring and

small-scale canopy disturbance if individual trees are killed. Care should be taken not to burn

under extremely dry conditions, as excessive injury or mortality may result. 

Figure 5.—

Conceptual representation of variable

density thinning in a

red pine stand,

including gaps,

unthinned areas, and

varying levels of thinning between these

extremes.

Unthinned Variable Density Thinning
Allow Appropriate Recovery Periods Between Regeneration Harvests

Allowing appropriate recovery periods between regeneration harvests will aid development of

structural and compositional complexity in red pine stands. Traditionally, red pine stands are

harvested before significant complexity has developed (fig. 6), a problem compounded when

stands are deliberately or inadvertently simplified during establishment. 

In general, economic rotation age is linked to culmination of mean annual increment; this

occurs somewhere between 50 and 90 years in unthinned red pine. If ecological complexity is

a primary goal, there is little reason to base rotation age for such a long-lived species only on

growth and economic factors. Rather, stands should be allowed to develop sufficient structural

and compositional complexity and spatial heterogeneity, a process that can be accelerated with

appropriate intermediate treatments. 

28

Figure 6.—

Development of 

ecological complexity

in a red pine stand

over time. Harvest Time since disturbance
Due to its limited genetic diversity, red pine does not demonstrate much disease resistance. 

Yet it is often used in reforestation because it has fewer damaging agents than other species.

Nonetheless, red pine can be damaged or killed by several diseases (table 9). Periodic 

outbreaks of these diseases, which typically affect young trees, can cause planting failures 

or reduced productivity of established plantations. 

Insect pests can work in concert with pathogens to further stress trees and increase their vulnerability to damage. To avoid this, it is important to recognize potential disease problems and

the risks they represent before planting trees or applying silvicultural treatments. 

Fortunately, it is often possible to reduce disease risk and minimize losses by establishing red

pine plantings on appropriate sites, timing silvicultural treatments to maintain high tree vigor,

and detecting and controlling insect and disease outbreaks as soon as possible. Managers

should emphasize long-term strategies that prevent or reduce the risk of disease outbreaks in

current as well as in future stands (table 10).

MAJOR DISEASES OF RED PINE

Illustrated publications to assist in the identification of the following red pine diseases, including descriptions of pathogen life cycles and management suggestions, are available online at

the following Web site and related links: http://na.fs.us/spfo/ and http://ncrs.fs.fed.us/.

Damaging Agents

Table 9.—Major red pine pathogens and tree classes affected

Pathogen Disease Tree class

Gremmeniella abietina Canker Seedling-sapling

Diplodia pinea Shoot blight, collar rot, and canker Seedling-pole

Sirococcus conigenus Shoot blight Seedling-sapling

Lophodermium seditiosum Needle cast Seedling-sapling

Coleosporium asterum Needle rust Seedling-sapling

Armillaria spp. Root and butt rot Seedling-pole

Heterobasidion annosum Root and butt rot Sapling-mature

Phellinus pini Trunk rot Mature

Inonotus tomentosus Root and butt rot Mature

29
30

Shoot Blight and Canker Diseases

Scleroderris canker.—Scleroderris canker, caused by the fungus Gremmeniella abietina, affects

primarily young trees, and seldom damages trees taller than 2 m. Because the disease develops

on lower branches under snow cover, it causes the most problems in frost pockets and areas

that receive deep snow. Planting red pine on sites favorable for disease development and 

inadvertently planting infected nursery stock have resulted in this disease becoming a major

problem in the Lake States and Northeastern States.

The Scleroderris fungus spreads through windblown spores (ascospores) that infect buds and

needles in spring, causing an orange discoloration at the base of affected needles. Infected

branch tips are usually dead by the following summer. The fungus can spread from the branch

into the main stem, where a canker develops that can girdle and kill young trees. The fungus

produces a second spore (conidiospore) that is disseminated by rain splash from dead branches to adjacent trees, increasing the disease incidence.

Preventing damage by Scleroderris canker begins with planting disease-free nursery stock and

avoiding planting sites where the fungus is already present or where frost pockets and cold air

drainage make seedlings especially susceptible. Pruning the lower branches on infected and

healthy trees will reduce incidence of this disease in high-value plantations.

Diplodia shoot blight and canker.—The fungus Diplodia pinea can cause epidemics of shoot

blight and cankers on trees stressed by drought or predisposed to infection through injury or

Table 10.—Guidelines to reduce or prevent the risk of disease outbreaks

Control strategies

Plant Control

Proper site healthy competing Avoid

Disease selection stock vegetation Sanitation wounding Pruning

Gremmeniella 

canker X X X X

Diplodia

canker X X X X

Sirococcus 

shoot blight X X X

Armillaria 

root rot X

Lophodermium 

needle cast X X

Needle rust X X

Heterobasidion 

root rot X X

Phellinus 

trunk rot X

Inonotus 

root rot X
31

poor site conditions. The fungus causes shoot blight on large trees, shoot blight and cankers

on sapling and pole-size trees, and shoot blight and collar rot on seedlings. Trees are infected

through succulent shoot tissues, branch stubs, or wounds caused by thinning and harvesting,

storm damage, hail, and insects. The fungus can grow from infected shoots into branch and

stem wood, developing cankers that often girdle or kill the tree. 

Infected residual trees and red pine windbreaks are often the sources of D. pinea inoculum.

The fungus can invade shoot tissues and persist without causing symptoms until infected trees

are stressed, at which time the disease develops rapidly. Multi-cohort management, including

seed tree and shelterwood regeneration, will increase the risk of disease if overstory and adjacent reserve trees are harboring inoculum. 

The risk of Sphaeropsis shoot blight and canker can be reduced by planting healthy stock

obtained from nurseries known to protect seedlings from infection and by not planting red

pine near infected trees in areas where the disease has previously been a problem. Since this

pathogen is especially damaging to stressed trees, poor sites where soil moisture is a limiting

factor should be avoided. Control of competing vegetation to maintain high tree vigor can also

reduce disease impact. 

Sirococcus shoot blight.—The fungus Sirococcus conigenus causes a shoot blight that periodically becomes epidemic in red pine plantations during extended periods of wet spring weather.

It damages or kills young red pine seedlings, saplings, and shoots on older trees. Trees growing

under or adjacent to infected red pine can be severely affected when conditions are optimum

for fungus dissemination and development. 

Spores (conidia) are released in spring and early summer. The fungus infects needles and

grows into the current year’s shoots. Unlike D. pinea, S. conigenus rarely enters older stem tissues,

thus it is a problem on older trees only after 2 or 3 years of severe disease. 

Outbreaks of Sirococcus shoot blight, like those of Diplodia shoot blight, are episodic and can

rapidly increase. Removing infected overstory trees and pruning infected shoots on understory

trees before spore dispersal in early spring will reduce the major sources of inoculum and minimize future disease incidence.

Needle Diseases

Lophodermium needle cast and Coleosporium needle rust.—Needle diseases such as

Lophodermium needle cast (caused by Lophodermium seditiosum) and pine needle rust (caused

by Coleosporium asterum) are often conspicuous on young trees but seldom damaging except in

nurseries and Christmas tree plantings. 

Pine needle rust is most severe on sites where its alternate hosts, goldenrod and aster, are

abundant; in such instances, it can limit growth and even kill young trees. Needle rust can be

reduced by avoiding planting on sites with goldenrod and aster unless they can be removed by

mowing or use of herbicides.
32

Root and Butt Rots

Armillaria root rot.—Armillaria shoestring root rot, caused by several species in the fungal

genus Armillaria, is common on stressed trees and trees weakened by insects or other diseases.

Many red pine trees are probably infected with Armillaria but exhibit symptoms only when

stressed by other biotic or abiotic factors. Fungal decay, which can extend several feet above

the ground, eventually girdles trees at the root collar, creating clusters of dead and dying trees.

Red pine trees growing on cutover hardwood sites are especially vulnerable, presumably

because of the increased source of inoculum in roots and stumps of harvested trees. 

Stunting and yellowing of infected trees are the first symptoms of disease. Mushrooms 

may develop at the base of infected trees in fall, producing windborne spores that can spread

the fungus. 

The incidence of Armillaria root and butt rot in red pine stands can be reduced by maintaining

high tree vigor. Planting on sites with evidence of diseased trees or with abundant hardwood

stumps that may harbor the fungus should be avoided.

Annosum root and butt rot.—Like Armillaria, Annosum root and butt rot (caused by the fungus Heterobasidion annosum) can result in clusters of dead and dying trees. Although Annosum

root rot has not been a widespread problem in red pine, it has the potential to cause damage

after thinning and harvesting in some stands.

Inonotus root and butt rot.—Inonotus tomentosus causes a root and butt rot of mature trees,

but it can also damage seedlings and young trees on sites where the fungus remains from the

previous stand. It infects trees through wounded roots and root collars, developing a resinous

canker. Affected trees have reduced growth and are susceptible to windthrow. 

Phellinus trunk rot.—Phellinus pini, which causes a white pocket rot in mature trees, is sometimes called red rot because of the color of the wood in the early stages of decay. Symptoms

include swollen knots, punk knots (masses of brown fungal hyphae protruding from decayed

branch stubs), and brown basidiocarps (conks) on trunks of infected trees. Infection enters

through wounds and broken branches. There are no effective control measures other than to

avoid wounding trees.

Insect Pests of Red Pine

Although numerous insects attack red pine, only a few represent serious, persistent, or widespread threats. These are reviewed below. 

Needle-Feeding Insects

Several defoliators can cause localized outbreaks in red pine that result in growth loss and

occasionally, tree mortality. The redheaded pine sawfly, Neodiprion lecontei, is most likely to

cause significant damage. The pine tussock moth, Dasychira plagiata, can also kill trees. Both

species eat both old (previous-year) and current-year needles, completely defoliating trees.

Most other defoliators found on red pine eat either old or current-year needles. 
33

Redheaded pine sawfly outbreaks have occurred throughout the Lake States. Feeding is heaviest

on young trees (less than 20 feet tall) and on sites that would be defined as stressful for red

pine—that is, highly disturbed sandy areas, frost pockets, and hardwood edges. 

Pine tussock moth outbreaks have occurred infrequently in the Lake States, generally in northwestern Wisconsin. Tree mortality has been reported following outbreaks.

The red pine needle midge, Thecodiplosis piniresinosae, feeds throughout the summer, but characteristic needle browning does not develop until late fall (see table 11). In early summer,

midge larvae tunnel into the base of needle fascicles. Feeding causes premature needle mortality,

referred to as fall browning or needle droop. Damage is often concentrated in the tops of

young trees, where terminal shoots may be killed. Persistent midge populations tend to be

associated with red pine plantations growing on poor sites. 

The Saratoga spittlebug, Aphrophora saratogensis, has probably been the most significant pest of

young red pine across northern portions of Michigan, Minnesota, and Wisconsin. Large spittlebug populations cause extensive wounding that can kill branches and eventually entire trees.

Plantation failures have been reported. High spittlebug populations are associated with abundant sweetfern, the plant that serves as a host for the insect’s immature stage. Several other

plants can also serve as alternate hosts including willows and raspberries/blackberries. 

Root and Root-Collar Insects

White grubs are the larvae of beetles referred to as May and June beetles. They live in the soil

and feed on fine roots of many plants, including young pine. They have been responsible for

planting failures throughout the Lake States region. Most damage occurs when planting into

existing sod. 

Table 11.—Common insect pests associated with different stages of red pine plantation development

Seedlings Saplings Pole-sized Mature and old growth

(1-5 years) (6-20 years) (21-40 years) (41-200+ years)

White grubs Saratoga spittlebug Ips bark beetles Ips bark beetles

Saratoga Root collar Root tip Red turpentine 

spittlebug weevil weevil beetle

European pine Red pine Red pine 

shoot moth shoot moth shoot moth

Redheaded Pine shoot Pine shoot 

pine sawfly beetle beetle

Red pine Red pine Red pine 

needle midge needle midge cone beetle

Pine tussock Pine tussock 

moth moth

Red pine 

cone beetle
34

The pine root collar weevil, Hylobius radicis, can be a serious pest of young (5- to 15-yearold) red pine. Larvae feed at the base of trees where they can girdle the stem or cause deformity. Heavily infested trees often break at the weakened area and tip over. Damage is associated with poorly stocked stands growing in heavy grass. Windbreak trees and trees growing

along the edges of plantations are most likely to be infested. Scotch pine (Pinus sylvestris) is

very susceptible to this weevil, and red pines growing in association with Scotch pines are

more likely to be infested. 

The root tip weevil, Hylobius rhizophagus, is most often found attacking red pine growing in

close association with jack pine. Infested red pines have flagged (dead) branches and often

appear stunted. The symptoms can be very similar to those resulting from Saratoga spittlebug

attacks or some of the shoot pathogens. 

Shoot-Mining Insects

European pine shoot moth, Rhyacionia buoliana, larvae feed on buds and shoots of red pine.

The worst damage occurs when heavy infestation causes the top whorl to lose dominance to a

branch on the lower stem. Damage tends to be corrected over time. This insect is limited to

lower Michigan, southeastern Wisconsin, and a few other locations where consistently heavy

snow cover provides optimum insulation for larvae during winter. 

The red pine shoot moth, Dioryctria resinosella, can also be a significant problem. Larval feeding on shoots can result in significant height and radial growth losses. 

Bark and Wood-Infesting Insects

Pine bark beetles in the genus Ips are associated with almost every red pine that dies. They are

generally viewed as secondary pests, and rarely attack plantations younger than 25 years of

age. Past that point, outbreaks are often associated with lack of thinning and drought.

Outbreaks are usually limited to small groups of trees, but during periods of significant

drought they can kill trees over several acres. Thinning and timber harvesting can also trigger

Ips outbreaks; freshly cut logs greater than 1 inch in diameter left in the woods in spring and

early summer can provide breeding sites for large beetle populations. 

The red turpentine beetle, Dendroctonus valens, is a common bark beetle that attacks trees from

the ground line up 3 to 4 feet. They create characteristic popcorn-like pitch tubes. These beetles are not considered tree killers but their tunnels and feeding reduce tree vigor, making

infested trees susceptible to infestation by Ips bark beetles. 

An exotic pine shoot beetle, Tomicus piniperda, has the potential to damage red pine stands in

the Lake States. Much like the native Ips beetles, this European beetle lays its eggs and develops

under the bark of stressed and recently killed pines. However, the adults also have a feeding

stage inside the shoots of host trees. High populations can result in heavy shoot mining and

significant loss of foliage. 
35

Seed and Cone Insects

Red pine has an array of insects that attack its reproductive structures, especially developing

second-year cones. The most significant of these is the red pine cone beetle, Conophthorus

resinosa, which can cause complete cone crop failures and adversely affect natural regeneration.

The greatest damage typically follows several years of high cone production. Because red pine

cone beetles spend the winter on the forest floor in hollowed-out shoots, prescribed fires conducted prior to beetle emergence in the spring offer excellent control potential.

Insects and Stand Development

Susceptibility to and incidence of pest species varies with stage of stand development (table

11). Seedlings have small root systems that can easily be damaged by root-feeding insects. 

In some situations, insect damage can be extensive in sapling stands prior to crown closure.

Plantation failures have been documented on sites dominated by sweetfern due to infestations

of Saratoga spittlebug. Many of these sites are also frost pockets. 

Root collar weevil can also be a serious pest of young red pine, especially on nutrient-deficient

sites. Improperly planted trees with j-roots are very susceptible, as are trees growing in heavy

sod. Because scotch pine is a favored host of this weevil, its presence may increase the likelihood of attack in nearby red pine. 

Defoliators like the redheaded pine sawfly and pine tussock moth can kill young trees.

Localized outbreaks of redheaded pine sawfly are most often associated with either dry, nutrient-poor sites or mesic, nutrient-rich sites. 

Shoot-mining insects do occur in young red pine stands but are relatively minor pests. The

European pine shoot moth damages terminal buds and can distort shoot growth. However, it

does not occur over most of the range of red pine in the Lake States. Red pine shoot moth

attacks can begin in plantations prior to crown closure, but most outbreaks have been reported

in slightly older stands. On rare occasions, white pine weevils will attack the terminal shoots of

red pine. 

Following crown closure, red pine pole stands are relatively immune to insect problems. 

Bark beetles in the genus Ips can kill small groups of trees, and larger groups of trees on rare

occasions. Ips bark beetles attack trees that are weakened by poor site conditions, drought, or

intense competition. Thinning stands to recommended stocking levels reduces stress and

decreases the likelihood of Ips infestations. 

The red pine shoot moth can pose a threat to plantations that are 20 to 40 years of age and

growing on sandy outwash soils. 

In some areas, the root tip weevil can kill pole-size pine outright. Root tip weevil is most

prevalent in northwestern and central Wisconsin and the western half of the Upper Peninsula.

The presence of jack pine intermixed with red pine increases the likelihood of infestations. 
Older red pines have the ability to defend themselves against insects and pathogens. One study

found that mature red pine trees (100 to 220 years old) have higher resin flow than younger

trees, giving them a defense against bark beetles. 

AVOIDING INSECT RELATED PROBLEMS

Because most insect-related problems in red pine are associated with specific site and stand

conditions, managers can avoid problems by knowing what these conditions are. Planting red

pine on appropriate sites will significantly reduce the likelihood of insect attacks. Managers

should use ecological classification systems such as habitat type guides to identify these sites. 

In addition, managers should follow these guidelines: 

1) Avoid planting into heavy grass competition. Grass competes with young trees for moisture

and nutrients, and existing sod can harbor high white grub populations. 

2) Avoid areas dominated by sweetfern. Incidence of Saratoga spittlebug is directly related to

abundance of sweetfern. If the site is already planted, eliminate the sweetfern. 

3) Avoid planting in frost pockets. Recurring frost stunts growth and reduces tree vigor, making trees more susceptible to insect injury. Saratoga spittlebug damage is often concentrated

in frost pockets. 

4) Use healthy seedlings and plant properly. Such seedlings will develop into fast-growing

young trees that are better able to withstand insect feeding than inferior seedlings. 

5) Avoid mixing red pine with Scotch pine under any circumstances. Jack pine can also spread

insects to red pine. White pine and some hardwoods are appropriate associates for red pine

on many sites. 

6) Thin red pine stands as recommended. High stand density can create competition stress,

making trees more susceptible to bark beetles. Thinning is best done in late summer, fall, or

early winter.

7) During spring and summer thinning operations, remove cut material larger than 4 inches

within 3 weeks. Winter-harvested material should be removed before warm spring weather

occurs. 

36
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38
Terminology is an important tool for communication. The following terms are taken from

Helms, J.A. (editor). 1998. The dictionary of forestry. The Society of American Foresters.

Bethesda, MD. 210 p.

Age class: a distinct aggregation of trees originating from a single natural event or regeneration

activity, or a grouping of trees

All-aged stand: a stand with trees of all or almost all age classes, including those of

exploitable age.

Clearcut: a stand in which essentially all trees have been removed in one operation.

Cohort: a group of trees developing after a single disturbance, commonly consisting of trees 

of similar age, although it can include a considerable range of tree ages of seedling or sprout

origin and trees that predate the disturbance.

Crop tree: any tree selected to become a component of a future commercial harvest.

Crown class: a category of tree based on its crown position relative to those of adjacent trees.

Crown cover, syn. canopy cover: the ground area covered by the crowns of trees or woody

vegetation as delimited by the vertical projection of crown perimeters and commonly

expressed as a percent of total ground area.

Crown density, syn. canopy density: the amount and compactness of foliage of the crowns of

trees or shrubs.

Crown ratio (live crown ratio): the ratio of crown length to total tree height.

Even-aged stand: a stand of trees composed of a single age class in which the range of tree

ages is usually ± 20 percent of rotation.

Extensive management: Management that balances timber and nontimber goals, generally

with limited capital investments. In addition to timber production, management for wildlife

habitat, water quality and quantity, recreation, biological diversity, and aesthetics are important.

Intermediate treatment: any treatment or tending designated to enhance growth, quality,

vigor, and composition of the stand after establishment or regeneration and prior to harvest.

Multiaged (multicohort) stand: a stand with two or more age classes or cohorts.

Natural regeneration: the establishment of a plant or a plant age class from natural seeding,

sprouting, suckering, or layering.

Appendix: Useful Forestry Terminology 

39
40

Overstory removal: the cutting of trees constituting an upper canopy layer to release trees or

other vegetation in an understory.

Partial cutting: removal of only part of a stand for purposes other than regenerating a new age

class; not considered a regeneration method.

Precommercial thinning (PCT): the removal of trees not for immediate financial return but to

reduce stocking to concentrate growth on the more desirable trees.

Production management: often associated with high capital investments to ensure rapid dominance by desired species and includes treatments such as planting genetically improved stock,

fertilization, competition control, thinning, and pruning.

Productivity: the capacity or ability of an environmental unit to produce organic material; the

relative capacity of an area to sustain a supply of goods and services in the long run.

Regeneration: seedlings or saplings existing in a stand; the act of renewing tree cover by establishing young trees naturally or artificially.

Regeneration cut: any removal of trees intended to assist regeneration already present or to

make regeneration possible.

Regeneration method: a cutting procedure by which a new age class is created; the major

methods are clearcutting, seed tree, shelterwood, selection, and coppice. Regeneration methods

are grouped in four categories: coppice, even-aged, two-aged, uneven-aged.

Release: a treatment designed to free young trees from undesirable, usually overtopping, competing vegetation. Treatments include cleaning, liberation, and weeding.

Reserve trees, syn. green tree retention: a tree, pole-size or larger, retained in either a 

dispersed or aggregated manner after the regeneration period under clearcutting, seed tree,

shelterwood, group selection, or coppice methods.

Reserve management: conservation or restoration of forest land without considerations for

financial returns or commodity goals. Can be either intrusive or nonintrusive in its impacts.

When the goal is to conserve or protect a natural area from human-caused disturbances

reserve management is nonintrusive. When the goal is to restore a condition or process, the

management applications may be quite intrusive and intensive, e.g., prescribed fire, removal

of exotic species. 

Residual stand: a stand composed of trees remaining after any type of intermediate harvest.

Riparian zone: a terrestrial area, other than a coastal area, of variable width adjacent to and

influenced by a perennial or intermittent body of water.

Rotation: in even-aged systems, the period between regeneration establishment and final

cutting.
41

Seed tree: a tree left standing for the sole or primary purpose of providing seed; a method of

natural regeneration.

Shelterwood: Stand is removed in a series of cuttings to promote the establishment of an

even-aged stand.

Site: the area in which a plant or stand grows, considered in terms of its environment, particularly as this determined the type and quality of the vegetation the area can carry. 

Site class: a classification of site quality, usually expressed in terms of ranges of dominant tree

height at a given age or potential mean annual increment at culmination.

Site index: a species-specific measure of actual or potential forest productivity (site quality,

usually for even-aged stands), expressed in terms of the average height of trees included in a

specified stand component (defined as a certain number of dominants, codominants, or the

largest and tallest trees per unit area) at a specified index or base age. The index is used as an

indicator of site quality.

Site preparation: hand or mechanized manipulation of a site, designed to enhance the success

of regeneration.

Site quality, syn. site productivity: the productive capacity of a site, usually expressed as volume production of a given species.

Stand improvement: an intermediate treatment made to improve the composition, structure,

condition, health, and growth of even- or uneven-aged stands.

Stand structure: the horizontal and vertical distribution of components of a forest stand

including the height, diameter, crown layers, and stems of trees, shrubs, herbaceous understory, snags, and down woody debris.

Stocking: an indication of growing-space occupancy relative to a preestablished standard.

Common indices of stocking are based on percent occupancy, basal area, relative density, and

crown competition factor.

Sustainability: the capacity of forests, ranging from stands to ecoregions, to maintain their

health, productivity, diversity, and overall integrity, in the long run, in the context of human

activity and use.

Thinning: a cultural treatment made to reduce stand density of trees primarily to improve

growth, enhance forest health, or recover potential mortality.

Thinning interval, syn. thinning cycle: the period of time between successive thinning

entries, usually in connection with even-aged stands.

Two-aged stand: a growing area with trees of two distinct age classes separated in age by more

than ± 20 percent of rotation.
Two-aged system: a planned sequence of treatments designed to maintain and regenerate a

stand with two age classes.

Underplanting: the setting out of young trees, or sowing of tree seed under an existing stand.

Uneven-aged stand: a stand with trees of three or more distinct age classes, either intimately

mixed or in small groups.

Uneven-aged system: a planned sequence of treatments designed to maintain and regenerate a

stand with three or more age classes.

Yield: the amount of wood that may be harvested from a particular type of forest stand by

species, site, stocking, and management regime at various ages.

42
Appendix A.—Site Index Curves for Red Pine From 

Different Regions of North America

Carmean et al. (1989) provided seven sets of site index curves for red pine using various

index ages. Although an index age of 50 is commonly used, some incorporate younger

index ages. These curves are representative of height growth patterns for red pine based

on total tree age, plantation age, and age measured at breast height (measured at 4.5 ft or

1.3 m above the ground) for specific regions across North America. In figures A1 and A2,

we provide a graphical comparison of these published site index curves from distinctly

different regions, grouping the curves according to a total or breast height index age.

Equations to reproduce these curves are presented in the table A1.

The curves using a total age index age for Minnesota, Wisconsin, and Ontario are based

on site indices of 50, 60, and 70 at an index age of 50. Site indices from Vermont are

based on site indices of 40, 50, and 60 at an index age of 30 (fig. A1). Curves from

Vermont indicate a more rapid early height. The Minnesota and Ontario curves have a

similar form. The curves from Wisconsin suggest lower productivity, in terms of height

growth, relative to other regions for red pine. The site index curves based on a breast

height index age for Ontario are based on site indices of 50, 60, and 70 at an index age of

50 years at breast height. Site indices from Illinois are based on site indices of 30, 40, and

50 at 25 years at breast height. Site indices from New York are based on site indices of 20,

30, and 40 at an index age of 20 years at breast height (fig. A2). Curves from Vermont

indicate a more rapid early height. The curves from Ontario indicate greater early height

growth and greater productivity, in terms of height growth, than those from New York and

Illinois. The curves from Illinois suggest productivity similar to the Ontario sites at

younger ages but low productivity at older ages. The curves from New York indicate less

productivity than those from Ontario but greater productivity than those from Illinois 

at older ages.

43
44

Table A1.—Parameter estimates for the equations used to create figures A1 and A2 (see Carmean et al.

(1989) for details on the derivation of the parameters)

Region b1 b2 b3 b4 b5 Reference

Total age

Minnesota 

Natural stands 1.8900 1.0000 -0.0198 1.3892 0.0000 Gevorkiantz 1957

Vermont Plantations 

(index age of 30 yrs) 2.0401 1.0003 -0.0361 1.7914 -0.0090 Hannah 1971

Wisconsin 

Plantations 2.6359 0.8259 -0.0389 21.5578 -0.6271 Wilde et al. 1965

Eastern Ontario 

Plantations 2.0434 0.9978 -0.0147 1.0937 -0.0035 Stiell and Berry 1973

Breast height age

New York Natural stands

(index age = 20 yrs bh) 19.0635 0.5885 -0.0111 3.3922 -0.3418 Richards et al. (1962)

Illinois Plantations

(index age = 25 yrs bh) 0.7666 1.0909 -0.0733 3.2335 -0.2947 Gilmore (1968)

Central Ontario

Natural stands 13.6713 0.5404 -0.0283 8.7720 -0.5308 Thrower (1986)
45

Figure A2.—

Comparison of site index

curves based on breast

height age from New

York, Illinois, and Ontario.

Site indices of 40, 50, and

60 are presented for each

group of curves. Equation

form: H = 4.5 + b1Sb2[1 -

exp(b3Abh)]b4(S^b5)

, where

H = total height in feet, S

= site index, Abh = breast

height age measured at

4.5 ft, and bi designates

parameter estimates 

provided in table A1.

Height 

Age at breast height (yrs)

New York 

Illinois

Ontario

125

100

75

50

25

0

0 10 20 30 40 50 60

Figure A1.—

Comparison of site

index curves based on

total age from

Minnesota, Vermont,

Wisconsin, and

Ontario. Site indices of

50, 60, and 70 are presented for each group

of curves. Equation

form: H = b1Sb2[1 -

exp(b3A)]b4(S^b5)

, where

H = total height in feet,

S = site index, A = total

age, and bi designates

parameter estimates

provided in table A1.

Height 

Total age (yrs)

Minnesota

Vermont

Wisconsin

Ontario

125

100

75

50

25

0

0 10 20 30 40 50 60 70 80 90 100 110 120
46
47

Appendix B.—Growth and Yield Equations and Tables

for Red Pine Basal Area, Cubic Foot, Cord, and Boardfoot Volume Growth

Table B1.—Tabulation of volume and d.b.h. prediction equations for red pine 

Stand volume prediction equations

V = 0.4085 BAH, where V = total volume (ft3 ac-1), BA = basal area (in.), H = tree height (ft)

(Buckman 1962)

V = 1.1606 BA1.0762H0.6228, where V = total volume (ft3 ac-1), BA = basal area (in.), H = tree

height (ft) 

(Walters and Ek 1993)

Vm = V exp(-0.9979(t/D)3.0445 + -2.2294N-0.2621(d/D)6.7081), where Vm = merchantable volume 

(ft3 ac-1), V = total volume (ft3 ac-1), D = quadratic mean d.b.h. (in.), N = number of trees per

acre, t = minimum merchantable top diameter inside bark (in.), d = minimum merchantable

d.b.h. (in.) (Mack and Burk 2004)

Individual tree volume prediction equations

V = 0.002979 D1.7143H1.1287, where 

V = total volume (ft3), D = d.b.h. (in.), and H = total tree height (ft) 

(Fowler 1997)

V = 0.0046 D1.8598H0.9299, where 

V = total volume (ft3), D = d.b.h. (in.), and H = total tree height (ft) 

(Gilmore et al. 2005)

V = 0.1202 D2.0565, where 

V = total volume (ft3), and D = d.b.h. (in.) 

(Gilmore et al. 2005)

Individual tree d.b.h. prediction from stump diameter 

D = 0.3462 + 0.7963Dstmp, where D = d.b.h. (in.), Dstmp= stump diameter (in.) measured at 6 in.

above ground

(Gilmore et al. 2005)

Individual tree volume prediction from stump diameter 

V = -8.417 + 1.8201 Dstmp, where V = volume (ft3), Dstmp= stump diameter (in.) measured at 6

in. above ground

(Gilmore et al. 2005)
48

Table B2.—Current annual basal area growth per acre for even-aged red pine stands by site, age, and

stand density

Stand density – basal area per acre

Total age Total height 30 60 90 120 150 180

Years Feet ------------------------- Square feet per acre -------------------------

SITE INDEX 75

20 30 6.2 6.9 7.4 7.6 7.6 7.2

40 61 4.9 5.7 6.2 6.4 6.3 5.9

60 86 3.8 4.6 5.1 5.3 5.2 4.8

80 103 2.9 3.7 4.2 4.4 4.3 3.9

100 115 2.2 3.0 3.5 3.7 3.6 3.2

120 124 1.6 2.4 2.9 3.1 3.0 2.7

140 130 1.3 2.1 2.6 2.8 2.7 2.3

160 134 1.1 1.9 2.4 2.6 2.5 2.1

SITE INDEX 65

20 26 5.5 6.3 6.8 7.0 6.9 6.5

40 53 4.2 5.0 5.5 5.7 5.6 5.3

60 74 3.2 4.0 4.4 4.6 4.6 4.2

80 89 2.3 3.1 3.5 3.8 3.7 3.3

100 100 1.5 2.3 2.8 3.0 2.9 2.6

120 107 1.0 1.8 2.3 2.5 2.4 2.0

140 112 .6 1.4 1.9 2.1 2.0 1.7

160 116 .5 1.3 1.8 2.0 1.9 1.5

SITE INDEX 55

20 22 4.9 5.7 6.2 6.4 6.3 5.9

40 45 3.6 4.4 4.9 5.1 5.0 4.6

60 63 2.5 3.3 3.8 4.0 3.9 3.5

80 76 1.6 2.4 2.9 3.1 3.0 2.6

100 85 .9 1.7 2.2 2.4 2.3 1.9

120 91 .4 1.1 1.6 1.9 1.8 1.4

140 95 -- .8 1.3 1.5 1.4 1.0

160 98 -- .6 1.1 1.3 1.2 .8

SITE INDEX 45

20 18 4.2 5.0 5.5 5.7 5.6 5.2

40 37 3.0 3.7 4.2 4.5 4.4 4.0

60 51 1.9 2.7 3.2 3.4 3.3 2.9

80 62 1.0 1.8 2.3 2.5 2.4 2.0

100 69 .2 1.0 1.5 1.7 1.6 1.3

120 74 -- .5 1.0 1.2 1.1 .7

140 78 -- .1 .6 .8 .8 .4

160 80 -- -- .5 .7 .6 .2

1BA growth = 1.6889 + .041066 (BA) - .00016303 (BA)2 - .076958 (age) + .00022741 (age)2 + .06441 (site index) (Buckman 1962).
49

Table B3.—Volume in cunits (100 cubic feet) per acre for even-aged red pine stands by site, age, and

stand density

Stand density – basal area per acre

Total age Total height 30 60 90 120 150 180

Years Feet --------------Cunits per acre---------------

SITE INDEX 75

20 30 3.7 7.3 11.0 14.7 18.4 22.0

40 61 7.5 14.9 22.4 29.9 37.3 44.8

60 86 10.5 21.0 31.6 42.1 52.6 63.2

80 103 12.6 25.2 37.8 50.4 63.0 75.6

100 115 14.1 28.2 42.2 56.3 70.4 84.5

120 124 15.2 30.4 45.4 60.7 75.9 91.1

140 130 15.9 31.8 47.7 63.6 79.6 95.5

160 134 16.4 32.8 49.2 65.6 82.0 98.4

SITE INDEX 65

20 26 3.2 6.4 9.5 12.7 15.9 19.1

40 53 6.5 13.0 19.5 25.9 32.4 38.9

60 74 9.0 18.1 27.2 36.2 45.3 54.3

80 89 10.9 21.8 32.7 43.6 54.5 65.4

100 100 12.2 24.5 36.7 49.0 61.2 73.4

120 107 13.1 26.2 39.3 52.4 65.5 78.6

140 112 13.7 27.4 41.1 54.8 68.5 82.2

160 116 14.2 28.4 42.6 56.8 71.0 85.2

SITE INDEX 55

20 22 2.7 5.4 8.1 10.8 13.5 16.2

40 45 5.5 11.0 16.5 22.0 27.5 33.0

60 63 7.7 15.4 23.1 30.8 38.6 46.3

80 76 9.3 18.6 27.9 37.2 46.5 55.8

100 85 10.4 20.8 31.2 41.6 52.0 62.4

120 91 11.1 22.3 33.4 44.6 55.7 66.8

140 95 11.6 23.2 34.9 46.5 58.1 69.8

160 98 12.0 24.0 36.0 48.0 60.0 72.0

SITE INDEX 45

20 18 2.2 4.4 6.6 8.8 11.0 13.2

40 37 4.5 9.1 13.6 18.1 22.6 27.2

60 51 6.2 12.5 18.7 25.0 31.2 37.4

80 62 7.6 15.2 22.8 30.4 37.9 45.5

100 69 8.4 16.9 25.3 33.8 42.2 50.7

120 74 9.1 18.1 27.2 36.2 45.3 54.3

140 78 9.5 19.1 28.6 38.2 47.7 57.3

160 80 9.8 19.6 29.4 39.2 49.0 58.8

1Cubic feet = 0.4085 (basal area x height) (Buckman 1962).

2Total main stem volume in cunits from 6-inch stump to tip of tree. Estimated cunits to a 4-inch top d.i.b. can be obtained by subtracting 1.067 (basal area per acre

in sq. ft. / ave. tree diameter in inches squared).
50

Table B4.—Current annual cubic foot growth per acre for even-aged red pine stands by site, age, and

stand density

Stand density – basal area per acre

Total age Total height 30 60 90 120 150 180

Years Feet --------------Cubic feet per acre---------------

SITE INDEX 75

20 30 101 131 158 182 203 218

40 61 142 180 210 232 246 253

60 86 147 188 218 237 246 244

80 103 131 174 204 221 225 217

100 115 110 154 184 199 200 188

120 124 85 129 158 172 171 159

140 130 72 117 146 159 156 137

160 134 63 109 139 152 149 130

SITE INDEX 65

20 26 80 108 132 152 169 183

40 53 108 140 166 185 198 206

60 74 109 144 168 185 196 195

80 89 92 128 150 168 172 165

100 100 66 104 130 143 143 136

120 107 48 86 112 124 124 110

140 112 30 69 94 106 104 93

160 116 25 64 89 100 96 78

SITE INDEX 55

20 22 61 83 103 119 133 144

40 45 80 107 129 145 155 160

60 63 75 106 128 143 151 150

80 76 56 87 109 121 124 118

100 85 36 69 91 103 105 96

120 91 19 48 71 86 86 74

140 95 -- 36 58 68 67 54

160 98 -- 26 48 57 54 39

SITE INDEX 45

20 18 45 63 79 93 105 114

40 37 56 77 94 109 117 121

60 51 47 72 90 101 106 105

80 62 30 56 73 83 86 80

100 69 9 36 53 63 64 59

120 74 -- 20 38 46 46 36

140 78 -- 6 23 30 32 20

160 80 -- -- 20 28 26 14

1Cubic feet growth = 0.4085 (basal area growth x height + height growth x basal area + basal area growth x height growth) (Buckman 1962).

Stand density – basal area per acre

Total age Total height 30 60 90 120 150 180
51

Table B5.—Volume in cords per acre for even-aged red pine stands by site, age, and stand density

Stand density – basal area per acre

Total age Total height 30 60 90 120 150 180

Years Feet --------------Cords per acre---------------

SITE INDEX 75

40 61 7.2 14.5 21.7 29.0 36.2 43.5

60 86 10.2 20.4 30.6 40.8 51.0 61.3

80 103 12.2 24.5 36.7 48.9 61.2 73.4

100 115 13.6 27.3 41.0 54.6 68.3 81.9

120 124 14.7 29.4 44.2 58.9 73.6 88.3

140 130 15.4 30.9 46.3 61.7 77.2 92.6

160 134 15.9 31.8 47.7 63.6 79.6 95.5

SITE INDEX 65

40 53 6.3 12.6 18.9 25.2 31.5 37.8

60 74 8.8 17.6 26.4 35.1 43.9 52.7

80 89 10.6 21.1 31.7 42.3 52.8 63.4

100 100 11.9 23.7 35.6 47.5 59.4 71.2

120 107 12.7 25.4 38.1 50.8 63.5 76.2

140 112 13.3 26.6 39.9 53.2 66.5 79.8

160 116 13.8 27.5 41.3 55.1 68.9 82.6

SITE INDEX 55

40 45 5.3 10.7 16.0 21.4 26.7 32.0

60 63 7.5 15.0 22.4 29.9 37.4 44.9

80 76 9.0 18.0 27.1 36.1 45.1 54.1

100 85 10.1 20.2 30.3 40.4 50.5 60.5

120 91 10.8 21.6 32.4 43.2 54.0 64.8

140 95 11.3 22.6 33.8 45.1 56.4 67.7

160 98 11.6 23.3 34.9 46.5 58.2 69.8

SITE INDEX 45

40 37 4.4 8.8 13.2 17.6 22.0 26.4

60 51 6.1 12.1 18.2 24.2 30.3 36.3

80 62 7.4 14.7 22.1 29.4 36.8 44.2

100 69 8.2 16.4 24.6 32.8 41.0 49.2

120 74 8.8 17.6 26.4 35.1 43.9 52.7

140 78 9.3 18.5 27.8 37.0 46.3 55.6

160 80 9.5 19.0 28.5 38.0 47.5 57.0

1Cords = 0.003958 (basal area x height). Rough cords for trees 3.6 inches d.b.h. and larger to a 3-inch top d.i.b. (Buckman 1962).

2Must be in trees 3.6 inches d.b.h. and larger.
52

Table B6.—Current annual cordwood growth per acre for even-aged red pine stands by site, age, and

stand density

Stand density – basal area per acre

Total age Total height 30 60 90 120 150 180

Years Feet --------------Cords per acre---------------

SITE INDEX 75

40 61 1.3 1.7 2.0 2.2 2.4 2.4

60 86 1.4 1.8 2.1 2.3 2.4 2.4

80 103 1.3 1.7 2.0 2.1 2.2 2.1

100 115 1.1 1.5 1.8 1.9 1.9 1.8

120 124 .8 1.2 1.5 1.7 1.6 1.5

140 130 .7 1.1 1.4 1.5 1.5 1.3

160 134 .6 1.0 1.3 1.5 1.4 1.3

SITE INDEX 65

40 53 1.0 1.4 1.6 1.8 1.9 2.0

60 74 1.1 1.4 1.6 1.8 1.9 1.9

80 89 .9 1.2 1.5 1.6 1.7 1.6

100 100 .6 1.0 1.3 1.4 1.4 1.3

120 107 .5 .8 1.1 1.2 1.2 1.1

140 112 .3 .7 .9 1.0 1.0 .9

160 116 .2 .6 .9 1.0 .9 .8

SITE INDEX 55

40 45 .8 1.0 1.2 1.4 1.5 1.5

60 63 .7 1.0 1.2 1.4 1.5 1.5

80 76 .5 .8 1.1 1.2 1.2 1.1

100 85 .4 .7 .9 1.0 1.0 .9

120 91 .2 .5 .7 .8 .8 .7

140 95 -- .3 .6 .7 .6 .5

160 98 -- .3 .5 .6 .5 .4

SITE INDEX 45

40 37 .5 .7 .9 1.0 1.1 1.2

60 51 .5 .7 .9 1.0 1.0 1.0

80 62 .3 .5 .7 .8 .8 .8

100 69 .1 .3 .5 .6 .6 .6

120 74 -- .2 .4 .4 .4 .3

140 78 -- .1 .2 .3 .3 .2

160 80 -- -- .2 .3 .2 .1

1Cordwood growth = .003958 (basal area growth x height + height growth x basal area + basal area growth x height growth) (Buckman 1962).

2Must be in trees 3.6 inches d.b.h. and larger.
53

Table B7.—Volume in M board feet per acre for even-aged red pine stands by site, age, and stand density

Stand density – basal area per acre

Total age Total height 30 60 90 120 150

180

Years Feet --------------M board feet per acre---------------

SITE INDEX 75

60 86 5.4 10.8 16.1 21.5 26.9 32.3

80 103 6.4 12.9 19.3 25.8 32.2 38.6

100 115 7.2 14.4 21.6 28.8 35.9 43.1

120 124 7.8 15.5 23.3 31.0 38.8 46.5

140 130 8.1 16.3 24.4 32.5 40.6 48.8

160 134 8.4 16.8 25.1 33.5 41.9 50.3

SITE INDEX 65

60 74 4.6 9.2 13.9 18.5 23.1 27.8

80 89 5.6 11.1 16.7 22.3 27.8 33.4

100 100 6.3 12.5 18.8 25.0 31.3 37.5

120 107 6.7 13.4 20.1 26.8 33.4 40.1

140 112 7.0 14.0 21.0 28.0 35.0 42.0

160 116 7.2 14.5 21.8 29.0 36.3 43.5

SITE INDEX 55

60 63 3.9 7.9 11.8 15.8 19.7 23.6

80 76 4.7 9.5 14.2 19.0 23.8 28.5

100 85 5.3 10.6 15.9 21.3 26.6 31.9

120 91 5.7 11.4 17.1 22.8 28.4 34.1

140 95 5.9 11.9 17.8 23.8 29.7 35.6

160 98 6.1 12.2 18.4 24.5 30.6 36.8

SITE INDEX 45

60 51 3.2 6.4 9.6 12.8 15.9 19.1

80 62 3.9 7.8 11.6 15.5 19.4 23.3

100 69 4.4 8.6 12.9 17.3 21.6 25.9

120 74 4.6 9.2 13.9 18.5 23.1 27.8

140 78 4.9 9.8 14.6 19.5 24.4 29.3

160 80 5.0 10.0 15.0 20.0 25.0 30.0

1Board feet = 2.084 (basal area x height). Board-foot volume by Scribner Dec. C. log rule for trees 7.6 inches d.b.h. to a 6-inch top d.i.b. (Buckman 1962).

2Must be in trees 7.6 inches d.b.h. and larger.

Stand density – basal area per acre

Total age Total height 30 60 90 120 150 180
54

Table B8.—Current annual board-foot growth per acre for even-aged red pine stands by site, age, and

stand density

Stand density – basal area per acre

Total age Total height 30 60 90 120 150 180

Years Feet --------------Board feet per acre---------------

SITE INDEX 75

60 86 751 959 1112 1211 1255 1245

80 103 670 887 1039 1126 1148 1105

100 115 560 785 936 1016 1023 958

120 124 433 659 807 878 871 812

140 130 365 595 743 810 795 699

160 134 320 556 709 777 762 662

SITE INDEX 65

60 74 556 737 856 943 999 993

80 89 467 654 766 860 878 841

100 100 339 531 661 728 732 694

120 107 242 440 571 634 630 560

140 112 153 352 482 541 530 472

160 116 127 327 454 509 491 400

SITE INDEX 55

60 63 382 539 655 732 769 765

80 76 286 445 556 619 635 602

100 85 185 352 466 527 534 488

120 91 95 247 361 436 436 379

140 95 -- 184 295 348 340 273

160 98 -- 135 244 291 276 201

SITE INDEX 45

60 51 242 365 457 516 542 537

80 62 155 284 374 425 437 410

100 69 48 182 273 320 325 300

120 74 -- 102 192 236 233 183

140 78 -- 29 116 155 161 103

160 80 -- -- 102 142 131 71

1Board-foot growth = 2.084 (basal area growth x height + height growth x basal area + basal area growth x height growth) (Buckman 1962).

2Must be in trees 7.6 inches d.b.h. and larger.
55

Table C1.—Rotation ages for maximum mean annual board-foot growth in red pine periodically thinned

to a given stand density, by site index

Basal area density after periodic thinning

Planted trees/acre 30 60 90 120 150 180 30 60 90 120 150 180

SITE INDEX 75

Rotation age – years Board feet per acre per year

400 63 93 103 113 118 103 331 614 831 980 1013 841

800 83 103 103 113 143 123 302 561 775 894 867 654

SITE INDEX 65

Rotation age – years Board feet per acre per year

400 93 83 103 103 123 98 247 471 654 774 732 618

800 83 103 103 133 148 118 237 447 605 676 583 415

SITE INDEX 55

Rotation age – years Board feet per acre per year

400 93 93 103 118 113 78 189 367 496 555 492 394

800 93 103 123 143 138 143 184 336 451 448 340 161

SITE INDEX 45

Rotation age – years Board feet per acre per year

400 98 108 123 118 88 88 124 245 336 329 263 263

800 103 123 128 138 -- -- 113 217 259 226 -- --

Source: Unpublished red pine yield tables for managed plantations and natural stands in the Lake States. Computer program developed by Lundgren (1971) from

growth and yield studies at the Northern Conifers Laboratory.

1International 1/4 inch board-foot volumes in trees 9 inches d.b.h. and larger to a 6- inch top d.i.b.

2Mean annual growth did not culminate prior to 153 years of age in these high-density stands.

Appendix C.—Rotation Ages Calculated at Various

Site Indices and Densities for Red Pine
Gilmore, Daniel W.; Palik, Brian J. 

2006. A revised managers handbook for red pine in the North Central Region.

Gen. Tech. Rep. NC-264. St. Paul, MN: U.S. Department of Agriculture, Forest

Service, North Central Research Station. 55 p.

This new version of the Red Pine Managers Guide gathers up-to-date information from many disciplines to address a wide range of red pine management issues.

It provides guidance on managing red pine on extended rotations with a focus 

on landscape-scale objectives along with the traditional forest management tools 

focusing on production silviculture. The insect and disease portion of this guide 

has been expanded to include the latest information on forest protection. 

KEY WORDS: Forest health, forest protection, growth and yield, landscape management, silviculture.

The U.S. Department of Agriculture (USDA) prohibits discrimination in all its programs and activities on the basis of

race, color, national origin, gender, religion, age, disability,

political beliefs, sexual orientation, and marital or family status. (Not all prohibited bases apply to all programs.) Persons

with disabilities who require alternative means for communication of program information (Braille, large print, audiotape, etc.) should contact USDA’s TARGET Center at (202)

720-2600 (voice and TDD).

To file a complaint of discrimination, write USDA, Director,

Office of Civil Rights, Room 326-W, Whitten Building, 14th

and Independence Avenue, SW, Washington, DC 20250-

9410, or call (202) 720-5964 (voice or TDD). USDA is an equal

opportunity provider and employer.
MISSION STATEMENT

We believe the good life has its roots in clean air, sparkling water, rich soil, healthy economies and 

a diverse living landscape. Maintaining the good life for generations to come begins with everyday

choices about natural resources. The North Central Research Station provides the knowledge and

the tools to help people make informed choices. That’s how the science we do enhances the 

quality of people’s lives.

For further information contact:

Or visit our web site:

www.ncrs.fs.fed.us

North Central 

Research Station

USDA Forest Service

1992 Folwell Ave., St. Paul, MN 55108