The Practice of Silviculture E-Book

Mark S. Ashton

• Herausgeber: John Wiley & Sons
• Kategorie: Wissenschaft und neue Technologien
• Sprache: Englisch

Seitenzahl: 2331

Veröffentlichungsjahr: 2018

Beschreibung

The most up-to-date, comprehensive resource on silviculture that covers the range of topics and issues facing today’s foresters and resource professionals 

The tenth edition of the classic work, The Practice of Silviculture: Applied Forest Ecology, includes the most current information and the results of research on the many issues that are relevant to forests and forestry. The text covers such timely topics as biofuels and intensive timber production, ecosystem and landscape scale management of public lands, ecosystem services, surface drinking water supplies, urban and community greenspace, forest carbon, fire and climate, and much more. 

In recent years, silvicultural systems have become more sophisticated and complex in application, particularly with a focus on multi-aged silviculture. There have been paradigm shifts toward managing for more complex structures and age-classes for integrated and complementary values including wildlife, water and open space recreation. Extensively revised and updated, this new edition covers a wide range of topics and challenges relevant to the forester or resource professional today. This full-color text offers the most expansive book on silviculture and: 

• Includes a revised and expanded text with clear language and explanations
• Covers the many cutting-edge resource issues that are relevant to forests and forestry
• Contains boxes within each chapter to provide greater detail on particular silvicultural treatments and examples of their use
• Features a completely updated bibliography plus new photographs, tables and figures

The Practice of Silviculture: Applied Forest Ecology, Tenth Edition is an invaluable resource for students and professionals in forestry and natural resource management.

Leseprobe

Table of Contents

Cover

Title Page

Preface

Acknowledgements

Part 1: Introduction to Silviculture

1 The History and Philosophy of Silviculture

Introduction

Silviculture, its Origin and Development as an Applied Ecology

The Philosophies of Silviculture as a Practice

Silviculture as a Body of Knowledge

References

2 Silviculture and its Place in Managing Current Forests and Woodlands

Introduction

The Purpose of Silviculture Today

Scope and Terminology of Silvicultural Practice

The Silviculture Framework for Managing a Forest

References

Part 2: Ecological Foundations of Silviculture

3 Ecological Site Classification, Stands as Management Units, and Landscape‐Scale Planning

Introduction

Ecological Methods of Identifying and Classifying Sites

Stands as Management Units

New Developments in Landscape‐Level Ecological Planning

References

4 Stand Dynamics: The Ecology of Forest Succession

Introduction

Initiating Disturbances and Sources of Regeneration

Stages of Stand Development

Defining Cohorts and Age Classes

Defining Canopy Stratification by Age Class

Relationship of Stand Dynamics to Other Interpretations of Vegetational Development

Choice of Developmental Patterns

References

5 Ecology of Regeneration

Introduction

Ecological Role of Natural Disturbance

The Regeneration Process

Disturbance, Climate, and Regional Patterns in Floristics of Forest Regeneration

Regeneration Methods as Analogs to Natural Disturbance

References

Part 3: Methods of Regeneration

6 Development of Silvicultural Systems and Methods of Regeneration

Introduction

Conceptual Formation of Silvicultural Systems: The Science of Place

Classification of Natural Regeneration Methods

Classification of Plantations and Artificial Seeding

Naming Silvicultural Systems: The Taxonomy

Summary Remarks

References

7 Site Treatments

Introduction

Disposal of Logging Slash

Treatment of the Forest Floor and Competing Vegetation

References

Part 3A: Natural Regeneration Methods

8 Natural Regeneration: The Clearcutting Method

Introduction

The Protocol

Regeneration of Pure Stands from Natural Seeding

Applications of True Clearcutting: Case Studies from North America

References

9 Natural Regeneration: The Seed-Tree Method

Introduction

The Protocol

Variations in Spatial Patterns of Stand Structure

Application of Seed‐Tree Methods

References

10 Natural Regeneration: The Shelterwood Method

Introduction

The Protocol for the Uniform Shelterwood

Protocols for Alternative Arrangements

Application of Shelterwood Methods

References

11 Natural Regeneration: Irregular Seed‐Tree and Shelterwood Methods (Multi‐Aged Systems)

Introduction

Development of Two‐ or Three‐Aged Stands

Regeneration Methods Including Reserve Trees within Irregular Seed‐Tree and Shelterwood Systems

Application of Two‐ or Three‐Aged Systems

References

12 Natural Regeneration: The Coppice Method

Introduction

Vegetative Regeneration and the Nature of Disturbance

The Physiology and Morphology of Sprouting

Types of Vegetative Regeneration

Simple Coppice Systems

Coppice Systems with Irregular Structures and Age Classes

The Role of Coppice Stands in the Past, Present, and Future

Conversion of Coppice Stands to High Forests

References

13 Natural Regeneration: Selection Methods

Introduction

The Protocol

The Selection Regeneration Method and its Variations

Managing for Balanced All‐Aged Stands

Managing for Unbalanced All‐Aged Stands

Application of the Selection Method of Regeneration

References

Part 3B: Methods Based on Artificial Regeneration

14 Species Selection and Genetic Improvement

Introduction

Selection of Species and Provenances

Genetic Improvement

References

15 Nursery, Planting, and Seeding Techniques

Introduction

Propagation

Planting and Seeding

References

16 The Arrangement, Composition, and Methods of Planting

Introduction

The Role of Planting

Density of Plantings

Spatial Arrangement of Plantings

High Forest Plantations

Low Forest Plantations

Protection of New Plantations

References

Part 4: Post‐Establishment (Intermediate) Treatments

17 Tree and Stand Growth

Introduction

Growth within Individual Trees

Stand Scale Patterns of Production

The Effect of Thinning on Stand Production

The Effect of Thinning on the Economic Yield of Stands

References

18 Post‐Establishment Tools in Silviculture

Introduction

Cutting and Girdling

Use of Herbicides

Methods of Applying Herbicides

Use of Insecticides

Prescribed Burning

Use of Fertilizer

Irrigation

References

19 Pruning Methods and Applications

Introduction

The Ecology of Natural Pruning Processes

Pruning Trees to Improve Timber Quality in Forests

Techniques of Pruning Open Grown Trees Within Urban Environments

Training and Pruning Fruit and Shade Trees in Orchards and Agroforestry Systems

References

20 Release Operations in Seedling and Sapling Stands

Introduction

Competing Vegetation

Concept of Free‐To‐Grow

Early Use of Release Treatments

Vegetation Control Methods

Timing and Extent of Release Treatments

Ecological Impact of Release Treatments on Plant Communities

Liberation Treatments

Release Treatments that Control Invasives

References

21 Methods of Thinning

Introduction

The Different Approaches to Thinning

Low Thinning

Crown Thinning

Dominant Thinning

Free‐Form Thinning

Variable‐Density Thinning

Geometric Thinning

Application of Thinnings

References

22 Quantitative Thinning: Theory and Application

Introduction

Conceptual and Experimental Proof for Thinning

Quantitative Thinning Guidelines

References

Part 5: Silvicultural Considerations for Managing All Forests

23 Conservation Management Practices

Introduction

Management Practices

References

24 Silviculture for Wildlife Habitat

Introduction

Habitat Elements Within Stands

Landscape Elements Across Stands

Examples of Application

Control of Wildlife Damage to Trees

References

25 Silvicultural Applications to Forest Restoration: Rehabilitation and Reclamation

Introduction

Degradation and Restoration Processes of Forests

Categories of Forest Degradation and their Restoration Treatments

Summary

References

26 Approaches to and Treatments for Maintaining Healthy Forest Ecosystems

Introduction

The Growing Threat of Non‐Native Invasive Insects and Disease

The Concept of Forest Ecosystem Health within Stand Dynamics

Protection Against Biotic Agencies: Insects and Disease

Protection Against Abiotic Agencies

Using Silviculture to Control Damage

References

27 Managing Forest Carbon in Changing Climates

Introduction

The Ecology of Forest Carbon

Avoiding Deforestation and Increasing Reforestation

Carbon Management in Existing Forests

The Use of Wood as Biomass Energyor in Wood Products for Carbon Storage

References

Part 6: Silvicultural Applications for Different Land Uses

28 Ecosystem Management: Managing Public Natural Forests for Multiple Values

Introduction

Regional and Global Differences in Public Land Ownership

Managing Complex Large‐Scale Forests

The Ecosystem‐Management Paradigm

Regional Examples of Ecosystem Management

References

29 Application of Silviculture to Watershed Management

Introduction

Baseline Watershed Conditions

Paired Watershed Studies: Impacts of Land Clearance and Forest Disturbance

Managing Forests for Water Quality: Examples from the United States

Managing Forests for Water Yield: Examples from the United States

Summary

References

30 Industrial Timber Management

Introduction

Principles of Regulating Timber Harvests

Considerations for Timber Production in Forests

Global and National Trends in Industrial Plantation Forestry

References

31 Application of Silviculture to Agroforestry

Introduction

Stages of Stand Development and Agroforestry

Successional Agri‐silvicultural Practices

Permanent Agri‐silvicultural Practices

Selection of Tree Species for Agroforestry

References

32 Application of Silviculture to Urban Ecosystems and the Urban–Rural Interface

Introduction

Aesthetics and Landscape Design of Urban Forests

Mitigating Urban Meso‐ and Micro‐Environments

The Application of Silviculture to Urban Watersheds

References

Common and Scientific Names of Trees and Shrubs Mentioned in the Text

Glossary of Terms

Index

End User License Agreement

List of Tables

Chapter 01

Table 1.1 Hectares

1

of land by geographic region of the world’s forests. Forests are defined here as woodlands and closed canopied forests; secondary forests of post agricultural origin or that have been logged and undisturbed forests. Primary undisturbed forest areas and their percent of total forest area are provided in parentheses.

Chapter 03

Table 3.1 Ecological attributes that can be measured to define benchmarks of natural forest pattern and process.

Table 3.2 Conceptual allocation of land uses using the triad approach for three geographic regions across North Carolina: (1) Appalachian Mountains; (2) Piedmont; and (3) the coastal plain.

Chapter 05

Table 5.1 The temporal and spatial processes of light, soil moisture, and soil nutrition, and examples of mechanisms that plants have used to capture resource availability.

Table 5.2 Autecology of tree propagules of forests and woodlands.

Table 5.3 Modes of pollination and related characteristics of flowers and fruits.

Table 5.4 Modes of dispersal and related characteristics of seeds or fruits.

Table 5.5 Attributes of trees that change in relation to amount of light for shade‐intolerant and shade‐tolerant trees, with attributes organized in order of increasing scale from leaf to stand.

Table 5.6 Shade tolerance rankings of some North American tree species in eastern and western American forests.

Table 5.7 Examples of North American forest types and species groups associated with disturbance: fire, water, and wind.

Chapter 06

Box 6.1 Table 1 Silvicultural strategies under risk‐averse and risk‐reward biophysical and socio‐economic circumstances.

Chapter 07

Table 7.1 Probable effects of harvest and site preparation treatments on nitrogen cycling.

1

Table 7.2 Examples of site treatments that can facilitate the germination and establishment of different kinds of natural regeneration and planted seedling stock.

Chapter 08

Table 8.1 Examples of the natural disturbance regimes of forest types and the species that can be regenerated by true clearcutting in North America.

Table 8.2 Site treatments that are often used with true clearcutting.

Chapter 09

Table 9.1 Examples of the natural disturbance regimes of forest types and species that can be regenerated by the seed‐tree method in North America.

Chapter 11

Table 11.1 A description of reserves used in irregular hybrid seed‐tree shelterwoods in southern New England.

Chapter 12

Box 12.2 Table 1 A comparison of production estimates of hybrid poplar from different regions of the United States. The variation is due in part to the different clones tested.

Chapter 13

Table 13.1 Diameter distributions exemplifying the results of different criteria used to determine these distributions for various kinds of pure uneven‐aged stands.

Table 13.2 Table from Tubbs and Oberg (1978) showing values of a coefficient

K

for determining the number of trees to be grown in uneven‐aged stands with diameter distributions of different amounts of basal area per acre and various

q

‐factors. Divide the chosen value of the stand basal area by the

K

‐value for the desired combination of the

q

‐factor and maximum DBH to determine the number of trees in the largest diameter class. To determine the number of trees in each 2‐inch class, multiply the number of trees in the next class with larger DBH by the

q

‐factor, as has been done for Table 13.1.

Box 13.1 Table 1 Ponderosa Pine – MASAM.

Table 13.3 Some examples of species and forest types suited to selection systems in North America. Almost all species can be managed through selection systems, but it is the nature of the site treatments and the size of the opening that define biological success while the strength of the market or social value that people desire that defines the socio‐economic feasibility.

Chapter 14

Table 14.1 Utility and service values in relation to species ecological category.

Chapter 15

Table 15.1 The factors to control, and methods of storing seeds.

Chapter 16

Table 16.1 Numbers of trees per unit of area for different approximately equivalent spacings, in traditional and S.I. (metric) systems, with arithmetic perfectly constant only within each system.

Table 16.2 A list of timber and pulpwood species and their affiliated taxonomic family commonly used for single‐species reforestation and plantation systems. Species are listed with their region/country of planting, climate type, and rotation length. This list accounts for almost 95% of all timber trees in plantations.

Table 16.3 The area extent of the plantation timber producing regions of the world in 2015.

Table 16.4 Common tree species found in silvopastoral, agroforestry, and fruit and nut orchard systems. For silvopastoral and agroforestry systems, tree species are listed by legumes and non‐legumes along with their region of planting and climate type (wet versus dry/arid; tropical versus temperate). Note that for agroforestry systems in dry or temperate climates, there are no common or widespread tree crops but many nurse tree species. In these climates most agroforestry crops are annual or seasonal food plants that can avoid the dry/winter seasons.

Table 16.5 A list of commonly planted temperate street tree species in North America and their site tolerances, characteristics, and stature at maturity.

Table 16.6 A list of compatible species mixtures for some temperate and tropical forest regions by shade tolerance, successional status, and suggested complementary and facilitative interactions (Binkley, 1983; Binkley

et al

., 1992; Forrester, Bauhus, and Cowie, 2005; Laclau

et al

., 2008; Kelty, 1992; Parrotta, 1999).

Table 16.7 Tropical and temperate tree species planted for their firewood values.

Chapter 17

Table 17.1 Girard form class values for several common North American tree species from the east. Values depict differences among regions and species. Greater values are associated with smaller‐statured trees on more nutrient‐ or drought‐stressed sites with lower productivity.

Table 17.2 Leaf to sapwood area of select tree species from the US Pacific Northwest. Sapwood is the functional part of the stem that conducts water. Water‐use efficient stems should have high sapwood area to leaf area ratio, meaning that a proportionally larger conductive system can supply a leaf area with water. Species that are from drier, more extreme sites, or that are more shade intolerant, have lower ratios than species from milder, wetter climates, or that are shade tolerant.

Table 17.3 (a) Biomass and energy transformation of a pitch pine, scrub oak stand on Long Island, New York. (b) All of the net primary production (NPP) was the result of photosynthesis in only 384 g/m

2

of leaf tissue. The table shows the distribution of the net annual primary production (g/m

2

) before the subtraction by consumption.

Table 17.4 Gross woody volume reduction from thinning by select timber tree species.

Chapter 18

Table 18.1 Commonly used herbicides: common and trade names, modes of application, and circumstances of use.

Table 18.2 Descriptions of the particulars for each herbicide that includes environmental concerns for

toxicity

and

volatility

.

Chapter 20

Table 20.1 A list of exotic plant invasives by region within the US and their control.

Chapter 21

Table 21.1 A comparison of the different approaches to thinning, their advantages and disadvantages, and the kinds of stand conditions that are most applicable to their use.

Chapter 22

Table 22.1 Stand density indices (SDIs) for a range of shade‐tolerant and ‐intolerant tree species. English units are number of 10‐inch trees per acre. Metric units are number of 25.5‐cm trees per hectare (CA, California; WA, Washington; OR, Oregon).

Chapter 23

Box 23.3 Table 1 Harvesting technologies. A list of operational characteristics by soil, treatment size, and complexity.

Table 23.1 Descriptions of a few important trees of cultural and sacred value that should be protected. There are many species and individuals that should actually be recognized but these are some examples.

Chapter 24

Table 24.1 Snag densities per acre by size class and by different managed and unmanaged forest types in North America. Size classes vary by study.

Table 24.2 (a) Amounts of dead wood (number per acre) by size class on the forest floor for different forest types and by kind of management. (b) Amount of coarse woody debris for different age classes (m

3

/ha).

Table 24.3 Almost all tree and shrub species have a wildlife value. Certain species of trees and shrubs can be defined as keystone or foundation species within forests of North America.

Table 24.4 The degree of temporal and spatial tree‐species diversity by regeneration method.

Chapter 25

Table 25.1 Summary of degradation effects and restoration choices progressing from less intensive to more intensive degradation phenomena and associated restoration treatments.

Chapter 26

Table 26.1 Forest insects and diseases that have severely impacted North America’s forests, subdivided by their origin (introduced or native), region (eastern or western North America), and by type (insects or pathogens).

Table 26.2 Abiotic pollutant stressors that have severely impacted North America’s forests, predisposing them to insects and disease.

Box 26.4 Table 1 Predicted changes in ecosystem processes in a northern hardwood forest with changing climate.

Chapter 28

Table 28.1 Approaches and considerations to ecosystem management in North America.

Table 28.2 Documented natural disturbance regimes that create openings within the canopy of the longleaf pine ecosystem.

Chapter 29

Table 29.1 (a) A comparison of the nutrient inputs in precipitation and outputs from streamflow of four watershed ecosystems in different physiographic regions of the US (modified after Swank and Crossley, 1988). Nutrients measured in kg/ha/yr. Walker Branch includes second‐growth Appalachian hardwood forest on limestone in a warm temperate climate; Coweeta includes second‐growth Appalachian hardwood forest on sedimentary shales and sandstones in a warm temperate climate; Hubbard Brook is second‐growth northern hardwood forest on nutrient‐poor granite in a cold temperate climate; and H.J. Andrews includes old‐growth Douglas‐fir/western hemlock forest on the west side of the Cascades on nutrient‐rich andisols of volcanic origin in a cold temperate climate. (b) Summary pools of nutrients above‐ and belowground for the four forest watershed ecosystems from contrasting physiographic regions. Nutrients in kg/ha.

Box 29.1 Table 1 Export patterns of dissolved nutrients and sediment from the Hubbard Brook experiment that deforested a complete watershed catchment followed by 3 years of herbicide application.

Box 29.1 Table 2 Export patterns of dissolved nutrients and sediment from the Coweeta Watershed deforestation experiment for a complete watershed catchment, where vegetation was allowed to come back immediately.

Box 29.2 Table 1 A summary of the watershed areas, their average yields (in millions of gallons per day), and the average withdrawal.

Chapter 30

Table 30.1 Companies with the largest sawtimber production in the world.

Table 30.2 The world’s largest wood fiber‐producing companies.

Box 30.1 Table 1 Land ownership changes in the US as of 2015.

List of Illustrations

Chapter 01

Box 1.1 Figure 1 An aerial view of swidden cultivation in the Amazon comprising a patchwork of current and abandoned fields.

Figure 1.1 Early agricultural civilizations of the world and their main crops.

Box 1.2 Figure 1 A diagram depicting Maya swidden succession. Maya succession nomenclature are (1) Ka’anal’k’aax: old tropical forest (30 or more years old); (2) Sak’aab (or Sak’ab): second year milpa; (3) Sak’aab‐kool: Recently abandoned milpa; early succession; (4) Kambal‐hubche’: 5–10 years old succession; (5) Kanalhubche’: 10–30 years old succession; (6) Kelenche’: 30–100 years old succession; (3‐6) Hubche’: secondary vegetation.

Box 1.2 Figure 2 An example of a tank cascade for a single watershed in northeast Sri Lanka.

Box 1.2 Figure 3 The ancient managed landscape of northeastern Sri Lanka. The tank cascade systems can be seen in the distance. Adjacent and downstream areas to the tanks are the cleared lands for paddy cultivation. The settlements with complex tree gardens are adjacent to the tanks on the upper ends along the margin in the middle of the picture. On higher ground is sacred forest associated with the temple that serves as watershed protection.

Box 1.3 Figure 1 An ancient sweet chestnut (

Catanea sativa

) wood pasture in Monmouthshire, Wales.

Box 1.4 Figure 1 Sir Dietrich Brandis.

Box 1.5 Figure 1 Gifford Pinchot.

Figure 1.2 Economic and social development process leading to a developed economy and the forms of silviculture practiced.

Figure 1.3

(a)

A global depiction of the world’s original forest (orange shading) and current undisturbed forests that have had little human impact (green shading).

(b)

A global depiction of the world’s current forest cover (as measured by tree density) including undisturbed and second growth forests that have been logged or reverted back post land clearance for agriculture.

Chapter 02

Figure 2.1 A graphical depiction of where the subject lies within the multi‐disciplinary training of a professional forester.

Figure 2.2 Much of silviculture has always consisted of rehabilitation efforts and of knowing what will happen as a result of treatments of the forest. This sequence of pictures from 1938, 1949, and 1969 shows a planted stand at a National Forest in northern Idaho, in three stages of development. The tract had been cut‐over from a logging railroad in 1930–1931 and was both burned and acquired just before the first picture

(a)

was taken. Planting of western white pine and Engelmann spruce was done in 1939 and 1940. The subsequent pictures

(b

and

c)

show the development to age 30, of the mixture of planted trees and other conifers that seeded‐in naturally.

Figure 2.3 The relationship between the period of regeneration and the period of intermediate cuttings is shown for a sequence of even‐aged stands managed on a 60‐year rotation according to the shelterwood system. In this system the new stand is started before the older one is completely removed.

Chapter 03

Figure 3.1 Depiction of a cover type and stand map for a division of The Yale–Myers Research and Demonstration Forest in northeastern Connecticut. The stands are identified by numbers. The cover types are depicted by color codes in the key.

Figure 3.2 Site index curves for loblolly pine based on stem analyses of trees growing in the coastal plains of Virginia, North Carolina, and South Carolina. These curves use base age 50 at breast height as the basis for measurement and indicate seven site classes ranging from 60 to 120 feet.

Figure 3.3

(a–e)

A series of photographs showing old‐growth forest vegetation characteristic of markedly different sites, each requiring correspondingly different silvicultural treatment, all in northern Idaho.

(a)

The lowest and driest site with a pure stand of ponderosa pine.

(b)

An open stand of ponderosa pine on a south‐facing, dry slope at middle elevations. A closed stand of the so‐called western white pine type, such as shown in c, occupies the opposite north‐facing slope.

(c)

A mixed stand of the western white pine type on a mesic north‐facing slope. The nearest tree is a western larch; the one to its left is a western white pine; the one with vertically striped bark to the left of that is a western redcedar; some of the understory saplings are white firs.

(d)

A 225‐year‐old stratified mixture of the western white pine type on a mesic valley‐bottom site below the stand shown in b. Among the other species present are western larch, western redcedar, and western hemlock, with the two latter species in the lower strata.

(e)

A pure stand of white‐bark pine characteristic of very cold sites at high elevations in the same locality as a and d.

Box 3.1 Figure 1

(a)

Topographic relief of a bottomland in the lower Mississippi.

(b)

An aerial depiction of topographic relief of the Red River, Arkansas, a tributary of the Mississippi River.

Figure 3.4

(a–c)

Ecological site classification for British Columbia with an example of the mountain hemlock type.

(a)

An illustration of the biogeographic climate forest zones of British Columbia.

(b)

A cross‐section of the Mountain Hemlock Zone physiography as an example of defining site differences within a forest climate zone. The Mountain Hemlock Zone is restricted to the subalpine elevations of coastal mountains of southwest British Columbia.

(c)

The temperature–moisture association with herbaceous indicator species for the Mountain Hemlock Zone. Soil nutrient regime: VP – very poor, P – poor, M – medium, R – rich, VR – very rich; soil moisture regime: W – wet, VM – very moist, M – moist, SD‐F – somewhat dry, MD – moderately dry.

Box 3.2 Figure 1 A physiographic cross‐section showing the relationship of some of the units to surficial geology and landforms.

Box 3.3 Figure 1 Typical examples of four different kinds of stand structures show the appearance of stands in vertical cross‐section and corresponding graphs of diameter distribution in terms of numbers of trees per unit of area. The trees of the first three stands are all of the same species. The third comprises a multi‐aged (three‐aged) stand. The fourth stand consists of several species, but all of the same age. (DBH, diameter at breast height).

Figure 3.5

(a)

A photograph of the foothills of the western Himalaya, India. Stands can easily be identified by marked differences in species composition across the topography. The drier spur ridges are dominated by a hard pine,

Pinus roxbughi

, while the slopes and gullies are dominated by evergreen oaks (

Quercus leucotrichophora

,

Q. floribunda

).

(b)

An aerial depiction of the forest canopy and its variations in tree density, species composition, and age class across varying sites. The white lines in the foreground define various stands based on crown density and size, and species composition. Yuganskiy Nature Reserve, Siberian taiga, Russia.

Box 3.4 Figure 1 Stand‐based land use map for the Plusnin and Curtis Divisions of the Yale‐Myers Research and Demonstration Forest.

Figure 3.6 Map and cross‐sectional profile of North Carolina (

A

–

A

) depicting the Appalachian Mountains (pale blue), Piedmont (green), and coastal plain (pale yellow) from west to east.

Chapter 04

Figure 4.1

(a)

Fire‐killed stand of lodgepole pine in western Montana. Natural regeneration of pines has started, and the fire eradicated the serious dwarf mistletoe infestation that caused the witches' brooms in the pines.

(b)

Stand of interior cedar–hemlock, British Columbia, that has been partially blown down by a convectional windstorm.

Figure 4.2 The same mixed stand at advancing stages of development, starting at the top with the stand initiation stage, then proceeding through the stem exclusion stage to the beginning of the understory reinitiation stage. Number and crown shapes identify the size of different species in the stand. Species: 1 – a short‐lived pioneer that cannot tolerate shade after being over topped; 2 – a longer‐lived pioneer that is a fast‐growing emergent; 3 – a late‐successional emergent with a delayed ascent to the tops of the canopy; 4 – a late‐successional species with slow initial development that reaches the main canopy; 5 – a long‐lived pioneer species with initial rapid development that is overtaken by species 4 but can withstand shade after being overtopped; and 6 – a very shade‐tolerant late‐successional species that usually remains in the lower strata. Figure 4.3 shows the same stand developing into old growth.

Figure 4.3 Continuation of the stand‐development sequence of Figure 4.2, starting late in the understory reinitiation stage and extending into the old‐growth stage. The five species have the same numbers as in Figure 4.2. Species 1 was too intolerant to become re‐established in the understory.

Figure 4.4 The Kraft Crown Classification (Kraft, 1884). The relative positions of trees in different crown classes in a single‐aged (even‐aged), pure stand. The letters D, C, I, and O denote dominant, codominant, intermediate, and overtopped crown classes, respectively. E, denoting an emergent crown class, is not depicted.

Figure 4.5 The process of differentiation into crown classes as a result of competition in a pure, single‐canopied, single‐aged stand, showing how some trees that were initially dominants may lose in the race for the sky.

Figure 4.6 An all‐aged stand of ponderosa pine in southern Oregon, after a group of mature trees has been removed to make a vacancy for establishment of regeneration.

Figure 4.7 Stages in the natural development of an untreated stratified mixture in an single‐aged stand of the eastern hemlock–hardwood–white pine type. The upper sketch shows the stand at 40 years with the hemlock (gray crowns) in the lower stratum beneath an undifferentiated upper stratum. At 70 years (middle sketch) the emergents (hatched crowns) have ascended above the rest of the main canopy, except for the white pine, which has only started to emerge. The lower sketch shows the stand as it would look after 120 years with the ultimate degree of stratification developed.

Figure 4.8 A single‐aged mixture of northern hardwoods, about 90 years old, in the Adirondack Mountains of New York. The emergents are the white pines at the left, and some white ashes in the middle, which are still nearly leafless in this spring picture. Sugar maples and yellow birches form the main canopy stratum with American beech in the understory stratum.

Figure 4.9 Two different categorizations of forest strata.

(a)

A single‐aged, mixed‐species, stratified stand showing four strata: A – canopy, B – subcanopy, C – understory, and D – groundstory.

(b)

A second‐growth tropical rainforest as an example of a single‐aged mixture with the following strata: emergent, canopy, under canopy, and shrub layer.

Figure 4.10 Profile diagrams for rainforests.

(a)

French Guyanan rainforest dominated by slow‐growing late successional leguminous trees. Trees with bold outlines depict canopy and emergent species. The dotted line denotes the canopy layer and above.

(b)

A mixed dipterocarp forest growing on fertile soils in Sarawak. The canopy is less broken with few emergents and a dominance of mixed dipterocarp tree species in the canopy (darker shading).

Figure 4.11 Successional development in which an old senescing stand of western larch in western Montana is dying and being replaced by subalpine fir and a few Engelmann spruce.

Chapter 05

Figure 5.1

(a)

A very hot crown fire as an example of a lethal disturbance. Nothing survives.

(b)

A large hurricane as an example of a release disturbance. The groundstory and root systems survive.

Figure 5.2 Graphics depicting the time of establishment, growth, and survival for tree species over successional time for

(a)

the relay floristics model, and

(b)

the initial floristics model. The lines depict the period of establishment and growth of a species. The thicker bars depict the period of canopy dominance.

Figure 5.3 A newly germinated pine seedling with the seed still encasing the cotyledons.

Figure 5.4

(a)

The dark shade within a young stem exclusion stage of an old‐field white pine stand in New England, US. Note the near complete absence of an understory.

(b)

The deep shade of a stem exclusion stage mixed dipterocarp forest with a stratified canopy of pioneers on top (

Macaranga peltata

) and late‐successional dipterocarps beneath (

Shorea

spp.) in a logged forest, Sri Lanka.

Figure 5.5 A depiction of the diurnal solar energy cycle between the earth’s surface and the atmosphere.

Figure 5.6

(a)

A conceptual diagram depicting pattern of direct solar radiation across a canopy in the equatorial latitudes (top illustration) where the sun passes overhead twice (spring and fall equinox) over the year such that total solar radiation across an opening is concentric with highest amounts in the center (the amounts actually available to regeneration will depend upon when the rains are for growing season); over an opening in the northern latitudes (middle illustration) above the tropic of cancer (23 degrees north) (which would be the exact opposite should it be in the southern latitudes); over northern latitude openings (bottom illustration) where much more radiation is received on southern aspects. SU, southern understory; SE, southern edge; C, center; NE, northern edge; NU, northern understory.

(b.1)

Means and variations of solar radiation (as measured by Global Site Factor, GSF),

(b.2)

soil moisture availability, and

(b.3)

soil nitrogen availability across three canopy openings, 1 year after creation on a sandy well‐textured soil (Adams Brook), a thin to bedrock glacial till (Powerline), and a deep, fertile glacial till (Kozey Rd) in southern New England. Measurements were made over one growing season (June 1–September 1). SU, southern understory; SE, southern edge; SC, southern center; NC, southern center; NE, northern edge; NU, northern understory.

Figure 5.7 The distribution of four species of

Entandrophragma

(African mahogany). Individual trees are depicted by the pink, blue, and green circles, in relation to soil nutrient availability [

(a)

calcium – oranges;

(b)

magnesium – yellows;

(c)

phosphorus – browns] on an old sedimentary oxisol in a Central African rainforest.

Figure 5.8 Not all forests grow on dry land, nor do all regenerate only from seeds. It may be anticipated that a good tree will develop from one of these 2‐year‐old stump sprouts of water tupelo in a very wet part of a flood‐plain or bottomland forest in Mississippi.

Figure 5.9 Ponderosa pine regeneration under difficult climatic circumstances in northern Arizona. Figures

(a)

and

(b)

show the same spot just after a group‐selection cutting in 1909 and again in 1938. The saplings of the second picture did not become established until abnormally favorable circumstances took place in 1919. Unusual May rains probably overcame the competitive effect of the grass cover.

Figure 5.10 Crescentic (left) and concentric (right) patterns of horizontal variation in the effects of microclimatic factors in circular openings at some mid‐latitude. The kinds of species favored by different kinds of shading and exposure are indicated in the crescentic pattern caused by direct solar radiation. Concentric patterns due to diffuse solar radiation and long‐wave radiation (e.g., frost) are more likely to appear during the development of established vegetation than to affect species composition. Recognition of these two kinds of microclimatic variation may help in deducing the factors governing regeneration and determining how to control it.

Figure 5.11 Recruitment frequency and pattern of regeneration of different functional and ecological species groups over the different stages of stand development after an initiating disturbance. Each of the horizontal graphs (kite diagrams) shows the time of appearance and the changing abundance of each of the different groups of species that are listed adjacent their respective diagram. Vertical hatching depicts regeneration of pioneers that establish immediately after a disturbance. The solid black depicts species groups that rely on advance regeneration established before the disturbance and subsequently released. Note that advance regeneration re‐establishes again when the seedlings that were released post‐disturbance eventually attain the canopy, and they become reproductively mature (understory reinitiation). The white lines post‐ceding the regeneration recruitment event for each species group represents when the seedlings that establish or are released attain canopy dominance in the forest. The breadth of the line defines dominance. For example the short‐lived pioneers achieve canopy dominance first, then the long‐lived pioneers and then late‐successional canopy trees. Depictions are shown for:

(a)

a moist temperate (e.g., oak–maple–hardwood) or tropical forest dominated by release‐type disturbances (note dominance of advance regeneration); and

(b)

a boreal interior forest (e.g., jack pine) dominated by lethal‐type disturbances (note absence of advance regeneration).

Figure 5.12 Illustrations of change in disturbance scale, type, and intensity, across different topographies.

(a)

Southwest Sri Lanka in mixed dipterocarp forest.

(b)

Interior boreal spruce–aspen forest, Canada.

Figure 5.13 Species demographics as depicted by stem distributions in a 62 acre (25 ha) spatially explicit plot for four site‐restricted

Shorea

spp. for a tropical rainforest in Sri Lanka. The topography is sloped with a river bisecting the plot from north to south and slopes away from the river with northwest and southeast aspect.

Shorea trapezifolia

(orange) chiefly occupies the southeast aspect while

S. disticha

(pink) occupies most of the northwest slope;

S. megistophylla

(blue) is restricted to the lower lying riparian areas and seeps;

S. worthingoni

(green) is restricted to the ridges and spurs on the northwest aspect.

Figure 5.14 Diagram depicting reproductive presence of four ecological groupings in relation to size of wind disturbance to the forest canopy.

Figure 5.15 In regenerating forests it is necessary to anticipate the development of all the vegetation and not just that of the desired species.

(a)

A Douglas‐fir seedling barely visible in front of a stake during the year after a cutting in a forest on an excellent site on the Oregon Coast.

(b)

The same tree 3 years later and almost submerged by red alders and thimbleberry bushes that were not apparent earlier.

Chapter 06

Figure 6.1 Young seedlings of Scots pine establishing after a clearcut, Finland.

Figure 6.2 A single‐aged (single‐cohort) stand of ponderosa pine, western larch, and other conifers in Flathead National Forest, Montana, after a seed‐tree cutting that will lead to the establishment of a second cohort composed of the same species.

Figure 6.3 The establishment of a single‐aged (single‐cohort) stand of western white pine, sugar pine, white fir, and ponderosa pine beneath the first cutting (preparatory cut) of a shelterwood in the Sierra Nevada mixed conifer forest, California.

Figure 6.4 An uneven‐aged stand managed as mixed species and all‐aged through single‐tree selection of Norway spruce, European beech, and silver fir in a farmer’s woodlot, Bavaria, Germany.

Figure 6.5 A simple coppice of European chestnut in southeast England, UK.

Figure 6.6

(a)

An 8‐month‐old irrigated and fertilized single‐species single‐aged planting of teak (

Tectona grandis

) on old fields in Honduras.

(b)

A 1‐year‐old mixed‐species single‐aged (single‐cohort) plantation of

Gliricidia sepium

(vegetative sticks),

Michelia champaca

, and

Swietenia macrophylla

(mahogany) in the central highlands, Sri Lanka.

(c)

Mixed‐species two‐aged plantation comprising an overstory of Caribbean pine and newly planted seedlings of dipterocarps (luan, meranti) in southwestern Sri Lanka.

(d)

Mixed‐species single‐aged (single‐cohort) stand of vegetative cuttings with standards – established tea cuttings with a spaced overstory of clove trees (

Syzygium aromatica

) and

Gliricidia sepium

in the central highlands, Sri Lanka.

Box 6.2 Figure 1 A depiction of age‐class distributions and the nature of how regeneration methods approach reflecting them either as unbalanced (even‐aged systems) or balanced (selection systems).

Box 6.2 Figure 2 A conceptual depiction of the different approaches to regenerating stands using even‐aged approaches.

Figure 6.7 An example of a decision model depicting a logical and descriptive way of naming silvicultural systems for natural regeneration methods: five questions to consider.

Figure 6.8 One‐and‐a‐half centuries of evolution in silvicultural practice in Bavaria illustrated in three stands at the Forest of the Technical University of Munich. The Scots pine stand in the background was established by direct seeding 150 years ago on soils degraded by long periods of overuse. On the left is a Norway spruce plantation established 70 years ago where the initial pines had been harvested and the soil had improved enough to allow the spruces to grow. On the right is a planted stand of mixed hardwoods, 30 years old, which represents the re‐establishment of a forest resembling the original one hundreds of years ago and believed to be resistant to many of the maladies that pure spruce plantations sometimes suffer.

Chapter 07

Figure 7.1 Broadcast burning in preparation for planting after clearcutting a mature stand of western white pine, western hemlock, and fir, Deception Creek Experimental Forest, Idaho. Note the large volume of defective grand fir and western hemlock felled before the burning. If this had been left standing, resulting dead snags might have become ignited in wildfires and spread burning embers far and wide.

Figure 7.2

(a)

Dense, 6‐year‐old natural regeneration of ponderosa pine resulting from very intensive site preparation at Blacks Mountain Experimental Forest on the eastern slope of the Sierra Nevada. Most of the slash was piled mechanically in windrows along the edge of the opening, which was created in a group‐selection cutting. During the next good seed year the area was disk‐plowed.

(b)

An example of a pile‐and‐burn treatment in a western larch and ponderosa pine stand in western Montana that had an establishment cut of a seed‐tree regeneration method, where the slash has been piled and the site scarified. Piles will be burned in the early spring when snow is still on the ground to prevent any possibility of escape.

Figure 7.3 A conceptual diagram illustrating the intensity of site treatments associated with methods of natural regeneration.

Figure 7.4 An old‐field stand of shortleaf pine invading abandoned agricultural land in the Arkansas Ozarks. Because the grass inhibits broadleaved species more than conifers, the new pine stand will be unnaturally pure.

Figure 7.5 Bulldozers with rolling drum choppers being used to destroy hardwood brush preparatory to planting pine on a dry, sandy site on the southeastern coastal plain.

Figure 7.6 “K‐G” blade. The sharpened blade is set at an angle so that it can be used to shear off the trees at or below the ground line; the upper bar pushes the trees over as they are being severed. The “stinger” at one end of the blade is used to split the stem of a large tree so that it can be cut off or pushed over in two passes of the machine.

Figure 7.7

(a)

A root rake attached to a bulldozer. The rake is designed to scarify the topsoil but not to remove it in soil preparation.

(b)

A steel chain dragged behind a skidder used to scarify soil surface for jack pine seed germination in Wisconsin.

Figure 7.8 A flat, poorly drained site in North Carolina bedded in preparation for planting loblolly pine. The raised beds or berms, on which the trees are to be planted, were cast up with a special plow and shaping device to provide ridges of aerated soil in which the roots can start their expansion.

Figure 7.9 Windrowing of stumps and logging debris and the effect that the associated scraping action can have in moving nutrients sideways. Both pictures show site preparation for planting on the Atlantic coastal plain in North Carolina.

(a)

An old photograph showing a very thorough job of concentrating the debris in a tight windrow.

(b)

Tall loblolly pines growing in the nutrient concentration of such a windrow to the left but with stunted and somewhat chlorotic seedlings on the center (with the survey rod) in the zone from which materials had been pushed with a root rake. Windrowing is rarely if ever practiced in the US, given its potential degrading effects on top soil.

Figure 7.10 Ground cover establishment in a newly established rubber plantation.

Figure 7.11 Examples of contouring and terracing on steep slopes.

(a)

Crop terraces in Guizhou, China, used to structurally prevent surface erosion and earth slips.

(b)

Hedgerows in southern England, UK, to confine livestock and mitigate soil erosion when the field is cultivated.

(c)

Contour tillage and the use of groundcovers to prevent surface erosion and promote infiltration.

(d)

Ditching in a tea plantation to prevent surface erosion and to guide excess water immediately off site.

Figure 7.12 Drainage canal with water‐regulation device, designed to move water off a very flat site in North Carolina. The road is made of soil dug from the ditches on either side of it. The canal is adjacent to the bedded area shown in Fig. 7.8.

Figure 7.13

(a)

Scots pine stands on drained peatland in Finland. The trees were absent or badly stunted before the drainage started 50 years ago. The surface has subsided about a meter because of decomposition from the aeration of the drained peat.

(b)

Bedding and mounding site preparation to improve microsite drainage for planting northern white cedar in the Upper Peninsula, Michigan.

Chapter 08

Figure 8.1 Seed dispersal patterns within a clearcut opening.

Figure 8.2 The pattern of operation to ensure seed dispersal by:

(a)

sequential strip clearcutting; or

(b)

alternate clearcutting of a stand.

(c)

A profile of stand development post clearcutting, showing the small difference in height due to regeneration lag of the strips that were cut last.

Figure 8.3 A young stand of naturally regenerated lodgepole pine with older stands adjacent to it.

Box 8.1 Figure 1 Pine forest type distributions for the major southern pine species of the southern states.

Box 8.1 Figure 2 Fifteen‐year‐old loblolly pine (

Pinus taeda

) being harvested in a strip clearcut. Slash is being chipped and the soil surface is being scarified for seed dispersal from the adjacent stand.

Box 8.2 Figure 1 A range map depicting the distribution of jack pine (

Pinus banksiana

) in North America.

Box 8.2 Figure 2

(a)

Two‐year‐old jack pine established after a clearcut with the slash disked and distributed for seed dispersal and germination.

(b)

Clearcuts and seed tree methods (see Chapter 9) arranged to mimic a natural fire pattern in Manitoba, Canada.

Chapter 09

Box 9.1 Figure 1 Seed‐tree cut for loblolly pine (

Pinus taeda

) with broadcast herbicide application prior to scarification.

Box 9.1 Figure 2 Seed‐tree cut for shortleaf pine (

Pinus echinata

) with slash that has been chopped and crushed, prior to prescribed burning.

Box 9.2 Figure 1 Longleaf pine–wiregrass ecosystems.

(a)

A prescribed fire completed in the fall, prior to seed fall beneath a seed tree cut. The burn was designed to kill hardwood competition back to the ground and to provide growing space for longleaf pine regeneration.

(b)

The grass stage of longleaf pine depicted with the foliage of three understory oak hardwood competitors (left to right: turkey oak, willow oak and blackjack oak).

(c)

The removal of the seed trees and the release from grass stage of a young stand of longleaf pine.

Figure 9.1 A birds‐eye view of seed‐tree arrangements using single trees, groups, and rows and strips. The usual method is to select trees singly and uniformly across the stand to maximize seed rain and dispersal as depicted in the single seed‐tree method, whereby the crowns of the trees are shown in green and their seed‐shadows are shown in grey. Trees need to be wind‐firm and to be prolific seed producers. Groups are used to reduce the edge effect and maximize solar radiation on the ground surface per unit area of crown or basal area. Groups provide structural support for unstable trees and shelter and habitat for wildlife. Strips and rows aligned along with the contours can be used on steep slopes to mitigate any potential for erosion and to facilitate logistics of harvesting.

Figure 9.2

(a, b)

The before and after seed‐tree treatment for a 95‐year‐old stand of loblolly pine in the Piedmont, North Carolina. The single‐tree method left about 10 trees/acre (25 trees/ha). The larger hardwoods were killed with herbicides and a prescribed burn killed the smaller hardwoods, disposed of the slash, and prepared the seedbed.

Figure 9.3

(a)

Scots pine (

Pinus sylvestris

) seed‐tree cut in Finland with 25–30 trees/acre (60–75 trees/ha); mean DBH 14 in (35 cm) with slash that has been chipped and taken off site and the soil surface has been scarified.

(b)

Ponderosa pine (

Pinus ponderosa

) seed‐tree cut with 8–10 trees/acre (20–25 trees/ha) in western Montana.

Figure 9.4 Black birch (

Betula lenta

) and black cherry (

Prunus serotina

) seed trees (4–5 per acre) in northern hardwood forest of the Allegheny Plateau, Pennsylvania.

Box 9.3 Figure 1 A seed‐tree cut for western larch and lodgepole pine. This example shows a seed tree in the foreground for western larch (8 seed trees/acre, 20/ha) in which the site preparation included chipping the coarser material and distributing the branches but it was not burned. This encouraged some germination of lodgepole and with more larch from the nearby seed trees. In the background is a true clearcut where the same site treatment was applied. Much of the larch seed that germinated came from the adjacent seed trees that were downwind.

Box 9.4 Figure 1

(a)

An example of what pigs can do to the soil as a site treatment if used carefully and for only a period of time. If left for a long period, serious damage can be done to the tree root systems.

(b)

A medieval illustration of beating the tree canopy to drop acorns to the pigs below.

(c)

An example of an old white oak wood pasture that had the understory burned repeatedly.

Box 9.4 Figure 2 An example of a seed‐tree cut for red and white oak in southern New England. The harvest was done in the fall. The slash has been chopped and crushed to the ground and where possible logging machinery has scarified the soil to help bury the acorns. In this photograph there are occasional reserves of small‐diameter sugar maple.

Box 9.5 Figure 1

(a)

Historical range of big‐leaf mahogany in the Americas.

(b)

The distribution of big‐leaf mahogany in a 1000 ha (~2500 acre) plot in Para, Eastern Amazonia, Brazil.

Box 9.5 Figure 2 A Milpa swidden, cleared within the rainforest of the Yucatan, Mexico and cultivated with beans, corn, and squash and subsequently abandoned. It is a perfect site for mahogany to regenerate if there is a nearby seed source as seen by the tree in the background.

Chapter 10

Figure 10.1 Examples of forest types and species that can be regenerated by the shelterwood method. The focus species of shelterwoods for each forest type are in bold. These species predominantly rely on advance regeneration for establishment. The darker the color green or blue, the more shade tolerant the species relative to its associates, and the more amenable to a shelterwood. Other species associates listed are mostly more shade intolerant and will regenerate (indicated by arrows) within a shelterwood, depending upon degree of canopy opening made during the establishment cut, and the nature of site preparation (if any). Shelterwoods with low shade are the most inclusive of all regeneration methods. Those with most shade are exclusive to shade‐tolerant advance‐regeneration species.

Figure 10.2 Two illustrations of the three stages to a uniform shelterwood for establishing regeneration.

(a)

A 70‐year‐old even‐aged mixed‐stratified hardwood stand that had a preparatory cut, taking out the lower canopy strata to increase understory light levels for germination of canopy tree seedlings. At 75 years (5 years after preparatory treatment) an establishment seed cut is performed where the canopy seed trees are spaced for shelter and the seedlings beneath can establish and grow. At 85 years, the overstory trees are removed and the approximately 10‐year‐old regenerating stand is released.

(b)

A 40‐year‐old loblolly pine stand that has a preparatory cut removing the smaller and overtopped trees at the same time as a prescribed burn to take out the hardwood understory. This is to increase light and expose mineral soil to secure some initial pine regeneration. At year 42, the canopy is spaced in an establishment cut to provide more light in the understory to establish the pine regeneration. A removal cut is done when the overstory is 45 years old to release the 3‐year‐old pine stand below.

Figure 10.3 Photographs of forest understories that need to be removed in preparatory treatments to secure advance regeneration.

(a)

Hayscented fern in an even‐aged, stratified, hemlock–hardwood forest of southern New England.

(b)

Kalmia

thicket (mountain laurel) in flower in a New England Forest.

(c)

Palm understory in hill dipterocarp rainforest in Malaysia.

(d)

Salal in a second‐growth Douglas‐fir forest.

Figure 10.4 Photographs depicting the establishment cutting of a uniform shelterwood for:

(a)

beech–Scots pine on sandy soils in central Germany that removes about half the basal area;

(b)

red oak–maple–black birch forest in southern New England that removes about two‐thirds of the basal area; and

(c)

balsam fir and red spruce in Maine that removes about one‐third of the basal area.

Figure 10.5

(a)

A graphic depiction and

(b)

a photograph of a one‐cut shelterwood 15 years after treatment for Appalachian mixed hardwood forest on former Westvaco land.

Figure 10.6

(a)

A diagram illustrating the progression of strips over time using preparatory (P), establishment (E), and removal cuttings (R). What is shown is the third entry into the stand where strips in R have been preceded by entries that have had preparatory (P) and establishment cuttings, strips in E have been preceded by preparatory cuttings and strips in P only received the preparatory cutting.

(b)

A photograph of a strip shelterwood for Norway spruce in the Czech Republic. The man is standing on the border between establishment and removal cuttings.

Figure 10.7 A graphic depiction of the different sequential phases of a group shelterwood. Areas demarcated by zone 1 are where the initial preparatory cuts are done opening up the canopy to facilitate regeneration. In 5 years an area demarcated as zone 2 is opened up around zone 1 to facilitate the establishment of regeneration in zone 1 and to prepare zone 2 for seedling germination. Five years later zone 3 opens up the canopy edges further, linking gap openings and further releasing regeneration in zone 2 while starting regeneration in zone 3. The final removal of the remaining canopy in zone 4 is done after enough edge light has facilitated regeneration beneath the remaining understory.

Figure 10.8 Photographs depicting

(a)

preparatory and

(b)

establishment phases for a group shelterwood in European beech stands in the Czech Republic, and

(c)

preparatory and

(d)

establishment phases in Norway spruce–silver fir in Bavaria, Germany.

Figure 10.9 Shelterwoods can be the most inclusive natural regeneration method for complex mixed‐species stands, in particular where the most shade‐tolerant species rely upon advance regeneration. By including multiple species in the successional cycle, the opportunity exists of harvesting many products from trees that mature over the course of stand development ending with the timber trees. Adding all tree and non‐timber species together increases the net present value of a stand by compatible stacking as compared to management for timber alone. A graphic illustration is shown for shelterwoods as sequentially successional cropping systems for non‐timber forest products in a mixed dipterocarp forest from tropical Asia and a northern hardwood forest from northeastern North America.

Figure 10.10 A shelterwood establishment cutting in a 74‐year‐old stand of eastern white pine in the Pack Forest in eastern New York. The establishment cutting was carried out 12 years prior to the photograph. The overstory is being used to reduce damage to the crowns of the seedlings from the white pine weevil.

Box 10.1 Figure 1 A shelterwood establishment cut in a mixed conifer stand leaving 20 trees/acre on the Stanislaus National Forest in the Sierra Nevada. Slash was piled and burned as a site preparation.

Box 10.2 Figure 1 Two‐year‐old white oak seedling sprouts.

Box 10.3 Figure 1 A typical understory of an Appalachian oak hardwood forest prior to a shelterwood.

Box 10.3 Figure 2 Regeneration release of vigorous yellow‐poplar regeneration after the establishment cut of a shelterwood.

Box 10.3 Figure 3 A prescribed burn treatment to the advance regeneration kills the yellow‐poplar and promotes re‐sprouting of the fire‐tolerant oak beneath.

Box 10.4 Figure 1 A map depicting the original range of mixed dipterocarp forest in tropical Asia. The black depicted in the map is lowland and hill mixed dipterocarp forest. This forest type dominates climates with high rainfall areas throughout southeast Asia.

Box 10.4 Figure 2 A young stand of mixed dipterocarps in stem exclusion 25 years after regenerating by the Malaysian Uniform System at Sungei Menyala, Malaysia. Note the uniformity of the pole‐sized stems.

Chapter 11

Figure 11.1 The general simplified pattern of structural development in a managed two‐aged, mixed‐species stand. An even‐aged (single‐aged) stratified mature stand in the top figure is harvested after two entries, progressively leaving scattered reserve trees of the shade‐tolerant sub‐canopy species in the center figure. In the bottom figure, the new age class has regenerated to form another mixed‐species stratified cohort. It is important to leave enough reserves of the original forest behind for the structure and species composition that is desired, but they must not impede the growth of the new regenerating cohort.

Figure 11.2 Group reserves of western larch after a clearcut. The reserves are purposely left for structure not as a source of seed. The site preparation involved burning and scarification of the stand.

Figure 11.3

(a)

The establishment cutting of an irregular shelterwood in the Sierra mixed conifer type comprising a 120‐year‐old pine–cedar canopy, fir of variable age mostly 40–60 years old, and a regenerating age class. Group reserves of white fir have been left with a spaced canopy of incense‐cedar, ponderosa pine, and sugar pine. Slash was chipped and moved off site.

(b)

A prescribed burn followed the establishment cutting to expose the mineral soil in the same Sierra mixed conifer stand. The removal cut will take out about half of the spaced canopy and some fir where it is considered impeding regeneration release.

Figure 11.4

(a)

A two‐aged stand of Scots pine and Norway spruce with the younger cohort of pine and some spruce originating after a seed‐tree cut. Sub‐canopy spruce was left as reserves along with most of the seed‐tree pines after the removal cutting 10 years ago.

(b)

A stratified three‐aged interior cedar–hemlock stand in the Adams Lake region of British Columbia. The majority of the stand originated 40 years ago after an irregular seed‐tree cutting with site treatments to reduce the fire risk (pile and burning). The 40‐year‐old mixture includes a canopy of birch and aspen, a sub‐canopy of Douglas‐fir and western white pine, and an understory of western hemlock and western redcedar. Reserves include 100‐ and 250‐year‐old Douglas‐fir, western hemlock, and western redcedar, with survivors from the cut and prior mixed‐severity fires.

Figure 11.5 An irregular shelterwood (two‐ to three‐aged) for longleaf pine with scattered and aggregated reserves. Site treatments included a prescribed fire prior to the establishment cut and again prior to the removal cutting. The youngest cohort has passed the grass stage and is about 2 years of age after release from the last prescribed burn.

Box 11.1 Figure 1

(a, b)

A graphic depiction of the changes in canopy‐tree spacing and reserve arrangement and number for second‐growth hardwood stands using the irregular seed‐tree/shelterwood continuum across the valley–ridge landscape of southern New England. The crown size and structure of the canopy trees on toe‐slopes are larger and the spacing further apart compared to those on ridge sites, where more smaller‐crowned and shorter‐statured canopy and sub‐canopy trees can be retained at both establishment and removal cuttings.

Box 11.1 Figure 2

(a)

A seed‐tree establishment cut on a mesic toe‐slope. There are three age classes present: the regenerating age class (see photo inset of oak seedling sprout) including a mixture of regeneration from heavy‐seeded tree species and pioneer tree species; the overstory mainly includes spaced 70 ft (20 m) oak, ash, and yellow‐poplar, and group reserves of sub‐canopy sugar maple and hemlock; the residual stand is even‐aged (80 years) originating as second growth after old‐field abandonment. There are scattered reserves of sugar maple wolf trees over 250 years old that were in the original pasture as shade trees. Site treatments included crushing slash and some intentional scarification with logging machinery. The harvest was done in the winter and photograph taken in the late spring (June). Inset: Advance regeneration of oak was small, sparse, and about 20 years old. Other advance regeneration included some shagbark hickory and more numerous sugar maple. Ash, yellow‐ poplar, paper birch, and the black birch and red maple coppice originated the growing season after the cut.

(b)

A mid‐slope shelterwood establishment cut. There are about three age classes in the stand. The regenerating age class includes a mixture of advance regeneration and pioneer species. The overstory is mainly red oak spaced about 50 ft (15 m) apart, with single‐tree and group reserves of sub‐canopy hemlock, sugar maple, white oak, and red maple. The majority of the residual stand is about 90‐year‐old trees, originating as second growth on an abandoned brush meadow used as a summer sheep pasture. There are scattered reserves of white and black oak wolf trees over 300 years old that were kept in the original meadow to provide shade for livestock. Patches of advance‐regeneration hemlock and white pine have been protected from a site treatment that crushed the laurel and slash to the ground. The removal cut will take about one‐half of the canopy trees and the rest will be left as reserve structure.

(c)

The establishment cut of a shelterwood on a ridge site. There are three age classes present. The regenerating age class is comprised mostly of 2 ft (0.6 m) tall oak and hickory advance regeneration. Few pioneer species are represented in this age class because of the partial shade and droughty soil conditions. The overstory oak and hickory is spaced at 30 ft (9 m) with single‐tree and group reserves of sub‐canopy red maple, pignut hickory, and white pine. The stand is about 100 years old, originating beneath old‐field white pine that was cut at the turn of last century (1900s). The removal cut will take about half of the canopy trees and the rest will be left as reserve structure.

Figure 11.6 History of forest cutting in northern Maine.

Figure 11.7 A stand in central Maine which has just been thinned, with removals from each of the strata and with sufficient opening of the lower‐most stratum to allow establishment of new advance regeneration. The canopy includes oak and eastern white pine, and the sub‐canopy is mostly hemlock, red maple, and beech.

Box 11.2 Figure 1

(a)

Profile A depicts the stylized and simplified condition of a ridge site stand, prior to regeneration treatment with slow‐growing late‐successional

S. worthingtonii–M. nagassarium

trees in the canopy (represented by light green crowns), and their advance regeneration in the groundstory as saplings and seedlings as small circles of the same color. Sub‐canopy tree species are represented by dark green vertical ovals and understory tree and shrub species by horizontal dark gray ovals. Profile B depicts the stand after the sub‐canopy has been removed to release growth of advance regeneration. Control of sprout growth of the understory and sub‐canopy species has been completed to insure the release of the shade‐tolerant slow‐growing canopy trees. Enough light has allowed some pioneers of stem exclusion to dominate in places as depicted by the open black circles. Profile C depicts the stand after at least one more entry, removing 50% of the canopy. Three age classes are now present of canopy dominant trees

S. worthingtonii

and

M. nagassarium

– the original canopy trees prior to start of treatments (illustrated by numbers 1, 3, 5, 7); their original regeneration that has now grown up as the 60‐year‐old canopy trees; and their advance regeneration waiting for the next partial canopy removal at year 90.

(b)

Profile A depicts the stylized and simplified condition of a valley site stand, prior to regeneration treatment with

S. megistophylla

and

D. hispidus

trees in the canopy (represented by paler green puffy and star‐shaped crowns). Sub‐canopy trees are represented by dark green vertically oval shapes and understory trees and shrubs have dark gray horizontally spreading shapes. The numbered trees are those that remain after treatment to grow further. The arrows point to advance regeneration of the canopy that are released in future canopy‐removal treatments. Profile B depicts the stand structure and composition 10 years after overstory removal with reserve trees (1, 2, 3) judiciously left behind because of ecological or economic value and can be removed only at the next regeneration entry in 50–60 years time. At 10 years the young stand is dominated in the canopy by pioneers of initiation (depicted by open horizontal green oval lines) and stem exclusion (depicted by open vertical ovals). The advance regeneration present before treatment has been released and grows more slowly beneath the pioneers. Profile C depicts an essentially even‐aged, mixed stratified stand after 40 years of growth and development, with a few older reserves left after the original cutting. No major intrusions have been done other than to harvest the early‐successional non‐timber forest products. The pioneers have either been harvested or died from being over‐topped by the current canopy of 40‐year‐old (plus)

S. megistophylla

and

D. hispidus

that was released originally as advance regeneration. Sub‐canopy and understory trees of the same age but largely of vegetative origin, fill out the strata. Understory re‐initiation of advance regeneration of the canopy tree has not yet started.

Box 11.2 Figure 2 A photograph of the topographic gradient with ridge, mid‐slope, and valley forest, treated to differing degrees of canopy removal by irregular shelterwoods.

Box 11.2 Figure 3

(a)

Cardamom shrub enrichment planted in the forest understory.

(b)

Cane (

Calamus

spp.) emerging into the canopy during the stem‐exclusion stage of stand development about 15 years after the establishment cutting.

(c)

Sugar palm (

Caryota urens

) being tapped for syrup that is boiled down into

(d)

cakes of brown sugar.

Chapter 12

Figure 12.1 A ring of very large stump sprouts of coast redwood surrounding the charred remains of a stump about 8 ft (2.4 m) in diameter near Santa Cruz, California.

Figure 12.2

(a)