Ecological Silvicultural Systems E-Book
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- Herausgeber: John Wiley & Sons
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- Sprache: Englisch
ECOLOGICAL SILVICULTURAL SYSTEMS Unleash the natural power and adaptability of forests with this cutting-edge guide For generations, silvicultural systems have focused largely on models whose primary objective is the production of timber, leading to drastically simplified forests with reduced ecological richness, diversity, and complexity. Ecological silviculture, by contrast, focuses on producing and maintaining forests with "all their parts"--, that is, with the diversity and flexibility to respond and adapt to global changes. Ecological silviculture seeks to emulate natural development models and sustain healthy forests serving multiple values and goals. Ecological Silvicultural Systems provides a comprehensive introduction to these approaches and their benefits tailored to diverse types of forests, designed for forest management professionals. It provides a series of exemplary models for ecological silviculture and surveys the resulting forest ecosystems. The result is a text that meets the needs of professionals in forestry and natural resource management with an eye towards sustaining healthy forest ecosystems, adapting them to climate change, protecting them from invasive species, and responding to changing market forces. Ecological Silvicultural Systems readers will also find: * Detailed treatment of forest ecosystems in North America, Europe, South America, and Australia * A broad field of contributors with decades of combined expertise on multiple continents * Discussion of pine woodlands; temperate hardwood forests, boreal forests, temperate rainforests, and more Ecological Silvicultural Systems is a useful reference for professional foresters, wildlife habitat managers, restoration ecologists, and undergraduate and graduate students in any of these fields.
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Table of Contents
Cover
Table of Contents
Title Page
Copyright Page
List of Contributors
Preface
Acknowledgments
1 The Context of Ecological Silviculture
1.1 What Is Ecological Silviculture?
1.2 How Does Ecological Silviculture Differ from Classical Commodity‐Focused Silviculture?
1.3 Why Is Ecological Silviculture Needed?
1.4 What Are the Foundational Concepts of Ecological Silviculture?
1.5 What to Expect from the Chapters that Follow?
References
2 Ecological Silviculture for Great Lakes Red Pine Ecosystems
2.1 Introduction
2.2 Characteristics of Red Pine Ecosystems
2.3 An Ecological Silvicultural System for Red Pine Ecosystems
2.4 Climate Change Considerations
2.5 Summary
References
3 Ecological Silviculture for Northern Hardwood Ecosystems of Northeastern U.S.
3.1 Introduction
3.2 Characteristics of Northern Hardwood Ecosystems
3.3 An Ecological Silvicultural System for Northern Hardwood Ecosystems
3.4 Climate Change Considerations
3.5 Summary
References
4 Ecological Silviculture in Douglas‐fir–Western Hemlock Ecosystems
4.1 Introduction
4.2 Characteristics of Douglas‐fir–Western Hemlock Ecosystems
4.3 Essential Elements of an Ecological Silvicultural System for Douglas‐fir–Western Hemlock Ecosystems
4.4 Real‐World Application of an Ecological Silvicultural System for the DF‐WH Ecosystem
4.5 Climate Change Considerations
4.6 Summary
References
5 Ecological Silviculture for Longleaf Pine Woodlands in the Southeastern U.S.
5.1 Introduction
5.2 Characteristics of Longleaf Pine Ecosystems
5.3 Development Model
5.4 Prevailing Silvicultural Systems
5.5 An Ecological Silvicultural System for Longleaf Pine
5.6 Climate Change Considerations
5.7 Summary
References
6 Ecological Silviculture for Southeastern US Pine‐Oak Forests
6.1 Introduction
6.2 Characteristics of Pine‐Oak Ecosystems
6.3 Development Model
6.4 Ecological Silvicultural Systems for Pine‐Oak Ecosystems
6.5 Climate Change Considerations
6.6 Summary
References
7 Ecological Silviculture for Lowland Wet Conifer Forest Lake States
7.1 Overview
7.2 Glacial History
7.3 Plant Community Composition
7.4 Historical Natural Disturbance Regime
7.5 Silvics of Black Spruce and Eastern Larch
7.6 Current/Conventional Silvicultural Approaches
7.7 Natural Development Model for Lowland Conifer Ecosystems
7.8 Ecological Silviculture System
7.9 Climate Changes Impact on Lowland Conifer Ecosystems
7.10 Summary
References
8 Ecological Silviculture for Southern Appalachian Hardwood Forests
8.1 The Southern Appalachian Mixed‐Oak Forests
8.2 Contemporary Forests of the Southern Appalachians
8.3 Structure, Composition, and Development of the Southern Appalachian Mixed‐Oak Ecosystem
8.4 Regenerating Upland Oak Forests in the Southern Appalachians
8.5 An Ecologically Based Silvicultural System for Mixed‐Oak Ecosystems
8.6 Climate Change Considerations
8.7 Summary
References
9 Ecological Silviculture for Yellow Birch–Conifer Mixedwoods in Eastern Canada
9.1 Introduction
9.2 Characteristics of Yellow Birch–Conifer Mixedwoods
9.3 An Ecological Silvicultural System for Yellow Birch–Conifer Mixedwoods
9.4 Climate Change Considerations
9.5 Summary
Acknowledgments
References
10 Ecological Silviculture of Black Spruce in Canadian Boreal Forests
10.1 Introduction
10.2 Characteristics of Black Spruce Forests
10.3 Black Spruce Forest Types
10.4 Developmental Model for Black Spruce Forests
10.5 Emulating Natural Dynamics of Black Spurce Forests with Sivliculture
10.6 Summary
References
11 Ecological Silviculture for Acadian Forests
11.1 Introduction and Context
11.2 Ecological Characteristics
11.3 Models of Disturbance and Stand Development
11.4 Restoration Challenges and Possible Pathways
11.5 Regeneration Treatments at the Mature Forest Stage
11.6 Silvicultural Systems Based on Natural Disturbance Parameters – The Acadian Femelschlag
11.7 Climate Considerations
11.8 Summary
References
12 Ecological Silviculture for Sierra Nevada Mixed Conifer Forests
12.1 Introduction
12.2 Characteristics of Sierra Nevada Mixed Conifer Forests
12.3 Natural Development Model
12.4 An Ecological Silviculture System for Mixed Conifer Forests
12.5 Climate Change Considerations
12.6 Using the Natural Development Model to Alter Existing Systems
References
13 Ecological Silviculture for Aspen Mixedwoods in Western Canada
13.1 Introduction
13.2 Natural Disturbance and Successional Dynamics
13.3 Current Silvicultural Approaches
13.4 Ecological Silvicultural Systems for Boreal Mixedwoods in Western Canada
13.5 Policy Challenges
13.6 Climate Change Considerations for Boreal Mixedwood Management
13.7 How Does This Bring Management Closer to Nature?
References
14 Ecological Silviculture for Interior Ponderosa Pine and Dry Mixed‐Conifer Ecosystems
14.1 Introduction
14.2 Characteristics of Ponderosa Pine and Dry‐Mixed Conifer Ecosystems
14.3 An Ecological Silvicultural System for Ponderosa Pine and Dry‐Mixed Conifer Ecosystems
14.4 Example Applications of Ecological Silviculture in Contrasting Initial Conditions
14.5 Climate Change Considerations
14.6 Summary
References
15 Ecological Silviculture for North American Pacific Coastal Temperate Rainforests
15.1 Introduction
15.2 Characteristics of Temperate Rainforest Ecosystems
15.3 An Ecological Silvicultural System for the Temperate Rainforest
15.4 Climate Change Considerations
15.5 Summary
Acknowledgments
References
16 Ecological Silviculture for Oak Ecosystems of the Central Hardwoods Region, USA
16.1 Introduction
16.2 Characteristics of Central Hardwood Forests and Woodlands
16.3 Natural Developmental Model
16.4 Ecological Silvicultural Systems for Central Hardwoods Ecosystems
16.5 Climate Change Considerations
16.6 Summary
Acknowledgments
References
17 Ecological Silviculture for Fennoscandian Scots Pine Ecosystems
17.1 Introduction
17.2 Structure, Dynamics, and Composition of Scots Pine Ecosystems
17.3 Dead Standing Kelo Trees as a Key Component of Fennoscandian Pine Forests
17.4 Evolution of Ecological Silviculture of Scots Pine Forests
17.5 Toward Ecological Silviculture for Scots Pine in Fennoscandia
17.6 Reconciling Economic Profitability with Biodiversity: A Case Study Using Any‐Aged Forestry
17.7 Ecological Silviculture in Fennoscandia: Policy Context and Future Prospects
17.8 Conclusions
References
18 Silvicultural Systems in the Mountain Ash Forests of the Central Highlands of Victoria, South‐eastern Australia
18.1 Introduction
18.2 Ecosystem Characteristics
18.3 Prevailing Silvicultural Systems in Mountain Ash Forests
18.4 Natural Development Model and Silviculture
18.5 The Challenges for Mountain Ash Silviculture: Climate Change and Other Drivers
18.6 A New Silvicultural Model for Mountain Ash Forests
Acknowledgments
References
19 Ecological Silviculture for European Beech‐Dominated Forest Ecosystems
19.1 Introduction
19.2 Characteristics and Natural Dynamics of European Beech‐Dominated Ecosystems
19.3 Conventional Silvicultural Approach
19.4 Ecological Silviculture for European Beech‐Dominated Ecosystems
19.5 Climate Change Considerations
19.6 Summary
References
20 Ecological Silviculture for Chilean Temperate Rainforests
20.1 Introduction
20.2 Characteristics of the Evergreen Forest Type (EFT)
20.3 Natural Developmental Model
20.4 An Ecological Silvicultural System for the Chilean Hardwood‐Dominated Evergreen Forest Type
20.5 Summary: Ecological Silviculture for Chilean Temperate Forests
Acknowledgments
References
21 The Place of Ecological Silviculture, Now and in the Future
21.1 Introduction
21.2 A Diversity of Approaches for a Diversity of Forests
21.3 Conclusions
References
Index
End User License Agreement
List of Tables
Chapter 2
Table 2.1 Silvical characteristics of tree species found in Great Lakes red ...
Table 2.2 A developmental model of red pine ecosystems.
Table 2.3 An ecological silvicultural system for red pine ecosystems.
Chapter 3
Table 3.1 Silvical characteristics of canopy tree species commonly found in ...
Table 3.2 A developmental model for northern hardwood forest ecosystems.
Table 3.3 An ecological silvicultural system for northern hardwood ecosystem...
Chapter 4
Table 4.1 Example of an ecologically‐based multi‐aged silvicultural system i...
Chapter 6
Table 6.1 Shade tolerance, moisture affinity class, and approximate maximum ...
Table 6.2 An ecological silvicultural system for mixed pine‐oak ecosystems d...
Table 6.3 An ecological silvicultural system for mixed pine‐oak ecosystems d...
Chapter 7
Table 7.1 Characteristic plant species of lowland conifer systems in the wes...
Table 7.2 Lowland conifer developed across different stages, years, actions,...
Chapter 8
Table 8.1 Attributes of developmental stages in southern Appalachian oak‐hic...
Table 8.2 An ecological silvicultural system for southern Appalachian mixed‐...
Chapter 9
Table 9.1 Ecological characteristics of (a) trees and (b) woody shrubs in ye...
Table 9.2 Summary of natural dynamics of yellow birch–conifer mixedwoods....
Table 9.3 Ecological silvicultural systems for yellow birch–conifer mixedwoo...
Chapter 11
Table 11.1 Silvical properties of major Acadian tree species.
Chapter 12
Table 12.1 Tree species of the Sierra Nevada mixed conifer forest with shade...
Table 12.2 Areas of misalignment between current practice and ecological sil...
Chapter 13
Table 13.1 Naturally occurring mixedwood stand conditions (1 through 7) and ...
Chapter 14
Table 14.1 Major conifer tree species and their key characteristics.
Table 14.2 Example structural conditions and potential ecologically based si...
Chapter 15
Table 15.1 Shade tolerance, preferred seed bed, mature tree height, and typi...
Table 15.2 An ecological silviculture system for the temperate rainforest.
Chapter 16
Table 16.1 Silvical characteristics for common species in Central Hardwoods ...
Table 16.2 A developmental model for oak‐dominated savannas, woodlands, and ...
Table 16.3 An ecological silvicultural system for oak‐dominated savannas, wo...
Chapter 17
Table 17.1 Comparison of some key differences between low‐retention even‐age...
Chapter 19
Table 19.1 Key traits of selected tree species found in beech dominated fore...
Chapter 20
Table 20.1 Some silvical characteristics of the main tree species in the har...
Table 20.2 A developmental model for evergreen forests in Chile, starting wi...
List of Illustrations
Chapter 1
Figure 1.1 Variable retention harvest in red pine‐dominated forests in north...
Figure 1.2 Variable density thinning (VDT) within 6‐ha harvest unit on the N...
Chapter 2
Figure 2.1 Distribution of red pine in the western Great Lakes region of Nor...
Figure 2.2 Old‐growth red pine forest: northern Minnesota, USA. Note multipl...
Figure 2.3 Trembling aspen root suckering in an opening of a mature red pine...
Figure 2.4 Examples of variable retention harvesting in red pine stands: (a)...
Figure 2.5 An example of variable‐density thinning (VDT) in a young forest s...
Figure 2.6 Variable‐density thinning (VDT) in a mature stage red pine stand....
Chapter 3
Figure 3.1 Distribution of northern hardwood forests in northeastern North A...
Figure 3.2 Old‐growth northern hardwood forest in New York, USA with fine‐sc...
Figure 3.3 (a) Group selection harvest initiating new cohort with (b) crop‐t...
Figure 3.4 Deadwood creation in (a) group opening to reflect pulses associat...
Figure 3.5 Legacy retention within (a) large patch opening emulating mesosca...
Figure 3.6 Planted hybrid American chestnut (left) and white pine (right) in...
Chapter 4
Figure 4.1 Conceptual model showing inherent tradeoffs in adopting an ecolog...
Figure 4.2 Variable retention harvest on BLM‐administered lands in western O...
Figure 4.3 Variable‐density thinning on BLM‐administered lands in western Or...
Chapter 5
Figure 5.1 Characteristic structure and composition of
mature
and
old
longle...
Figure 5.2 (a) Natural longleaf pine seedlings (b) frequently form dense pat...
Figure 5.3 Generalized structure and composition of longleaf pine (LLP) fore...
Figure 5.4 Summary of ecological silvicultural practices for longleaf pine (...
Figure 5.5 Progression of plantation development toward mature stage with yo...
Figure 5.6 Longleaf pine seedlings planted under an 80‐year‐old slash pine c...
Chapter 6
Figure 6.1 The vernacular region known as the Upland South of the eastern Un...
Figure 6.2 Pine‐oak mixedwoods in the southeastern United States may occur a...
Figure 6.3 In natural, old pine‐oak mixedwoods of the southeastern United St...
Figure 6.4 The size and shape of natural, intermediate‐severity canopy distu...
Chapter 7
Figure 7.1 Early vegetation response of peatland forests to Greenwood fire i...
Figure 7.2 Tree age (based on tree core data) vs diameter at breast height (...
Figure 7.3 (a) Overhead of SPRUCE (Spruce and Peatlands Response Under Chang...
Chapter 8
Figure 8.1 Location of Ecological Subsections forming the southern Appalachi...
Figure 8.2 Distribution of forestland in the southern Appalachians by forest...
Figure 8.3 Growth release events (a) and establishment (b) of dominant speci...
Figure 8.4 Sorting of common species as a function of their tolerance for sh...
Figure 8.5 Multi‐aged oak‐hickory forest, Bent Creek Experimental Forest, No...
Figure 8.6 Estimates of forest stand age, adaptability score, and Shannon‐We...
Chapter 9
Figure 9.1 Distribution of the temperate mixedwood forest in the province of...
Figure 9.2 Main tree species associated with temperate mixedwood forests in ...
Figure 9.3 Mature (a) and old‐growth (b) yellow birch–conifer mixedwoods sho...
Figure 9.4 Structural legacies in yellow birch–conifer mixedwoods. (a) Old r...
Figure 9.5 (a) Natural canopy gap in a yellow birch–conifer mixedwood. (b) S...
Figure 9.6 Examples of developmental and successional stages of yellow birch...
Figure 9.7 Silvicultural treatments that enhance compositional and structura...
Chapter 10
Figure 10.1 Distribution of black spruce forests in North America.
Figure 10.2 Geographic distribution of species associated with black spruce ...
Figure 10.3 Development of the black spruce–feathermoss forest type accordin...
Figure 10.4 Even‐aged black spruce stands regenerated after a fire in the Mo...
Figure 10.5 Summary of the major developmental stages of black spruce‐domina...
Figure 10.6 Successional stages of black spruce forests: (a) after forest fi...
Figure 10.7 Examples of experimental shelterwood treatments undertaken in 20...
Figure 10.8 Characteristics and spatial patterns of four experimental partia...
Chapter 11
Figure 11.1 Map of the Acadian Forest.
Figure 11.2 Old‐growth red spruce stand in northern Maine, USA.
Figure 11.3 Recruitment age‐class distributions for three old‐growth red spr...
Figure 11.4 Densely stocked mature second‐growth red spruce stand in western...
Figure 11.5 Age distribution of red spruce trees from five mature second‐gro...
Figure 11.6 Young (age 25) even‐aged balsam fir stand treated 15 years prior...
Figure 11.7 Group selection cutting in a mature red spruce mixedwood stand o...
Figure 11.8 Map of gap locations and expansions over three 10‐year cutting c...
Figure 11.9 Typical gap in the AFERP experiment, showing permanent legacy tr...
Chapter 12
Figure 12.1 A conceptual model of natural development in MCF following a can...
Figure 12.2 A low‐severity fire that thinned a patch of young trees with a h...
Figure 12.3 Relationship between relative frequency and gap size under the c...
Chapter 13
Figure 13.1 The Canadian boreal forest region with the boreal mixedwood show...
Figure 13.2 Unmanaged boreal mixedwoods. (a) Recent wildfire on a mixedwood ...
Figure 13.3 Elements of ecological silvicultural systems for boreal mixedwoo...
Figure 13.4 Partial harvesting of aspen with protection of understory spruce...
Figure 13.5 General trend in merchantable volume for spruce and aspen for st...
Chapter 14
Figure 14.1 Felling a large diameter ponderosa pine using a crosscut saw Col...
Figure 14.2 A dry mixed‐conifer forest dominated by large, old, fire‐resista...
Figure 14.3 Structural conditions in contemporary active frequent fire regim...
Figure 14.4 Stem map showing the mosaic stand structure of individual trees,...
Figure 14.5 A decadent, old ponderosa pine tree showing claw marks from repe...
Figure 14.6 Conditions during (left) and after (right) prescribed fire treat...
Figure 14.7 Cut‐to‐length harvester (left) and forwarder (right) system bein...
Chapter 15
Figure 15.1 Distribution of the temperate rainforest along the Pacific coast...
Figure 15.2 Examples of VRH in temperate rainforest ecosystems. (a) Multi‐pa...
Figure 15.3 Example of multi‐pass VRH for maintaining multiple age cohorts s...
Figure 15.4 Red alder planted to enhance biodiversity in southeast Alaska.
Figure 15.5 Gap centered over residual bigleaf maple (9‐m radius) and plante...
Chapter 16
Figure 16.1 Central Hardwoods Region of the United States.
Figure 16.2 Representative plant species and structural conditions associate...
Figure 16.3 Stocking guide [16] that illustrates thresholds for managing sav...
Figure 16.4 Stages of development for Central Hardwoods forests managed with...
Chapter 17
Figure 17.1 Illustration of spatially heterogeneous patchy structure of a Sc...
Figure 17.2 Typical mature forest structures, and disturbance and regenerati...
Figure 17.3 Kelo trees in Kalevala National Park in northwest Russia. Keloa ...
Figure 17.4 Areas of different types of management prescriptions during 50 y...
Figure 17.5 Illustration of typical treatment schedules selected for differe...
Figure 17.6 Development of large tree, deadwood, and broadleaf volumes and t...
Figure 17.7 Total volume of new large‐sized pine deadwood (dbh >30 cm) in th...
Chapter 18
Figure 18.1 The location of the Central Highlands of Victoria, southeastern ...
Figure 18.2 Stages of harvesting in clear‐cutting in Mountain Ash forests. P...
Figure 18.3 Retention islands in a cutblocks subject to variable retention h...
Figure 18.4 High‐intensity regeneration burns damaging a retention island wi...
Figure 18.5 A cutblock in the Central Highlands of Victoria that was origina...
Figure 18.6 Conceptual model showing the differences in stand structural com...
Chapter 19
Figure 19.1 Beech‐dominated ecosystems are widespread across the temperate r...
Figure 19.2 Typical “messy” damage patterns from intermediate severity distu...
Figure 19.3 Advance regeneration of beech in oldgrowth (left) and managed (r...
Figure 19.4 Typical structural features of beech‐dominated ecosystems in an ...
Figure 19.5 Typical beech‐dominated forest landscape managed with a conventi...
Figure 19.6 An ecological silvicultural system for beech‐dominated forest ec...
Figure 19.7 Structural complexity resulting from irregular shelterwood harve...
Figure 19.8 Hypothetical 900 ha landscape depicting spatial and temporal har...
Chapter 20
Figure 20.1 Distribution of the EFT in Chile, showing its dominance in the C...
Figure 20.2 Interior of an old‐growth (left) and a secondary mixed‐species f...
Figure 20.3 A landscape of standing dead trees and other legacies, plus abun...
Figure 20.4 Variable‐density thinning in secondary forests of the evergreen ...
Figure 20.5 An irregular shelterwood in a mature forest dominated by Coihue ...
Figure 20.6 A stand with a selection cut immediately after its implementatio...
Chapter 21
Figure 21.1 General locations of forest systems and associated ecological si...
Figure 21.2 Frequency of regeneration methods used in ecological silvicultur...
Guide
Cover Page
Title Page
Copyright Page
List of Contributors
Preface
Acknowledgments
Table of Contents
Begin Reading
Index
Wiley End User License Agreement
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Ecological Silvicultural Systems
Exemplary Models for Sustainable Forest Management
Edited by
Brian J. Palik
USDA Forest Service Northern Research Station
Grand Rapids, MN, USA
Anthony W. D'Amato
Rubenstein School of Environment and Natural Resources University of Vermont
Burlington, VT, USA
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Library of Congress Cataloging‐in‐Publication DataNames: Palik, Brian, editor. | D’Amato, Anthony W., editor.Title: Ecological silvicultural systems : exemplary models for sustainable forest management / Brian J. Palik, Anthony W. D’Amato.Other titles: Exemplary models for sustainable forest managementDescription: First edition. | Hoboken, NJ : Wiley, 2024 | Includes index.Identifiers: LCCN 2023023190 (print) | LCCN 2023023191 (ebook) | ISBN 9781119890904 (paperback) | ISBN 9781119890928 (adobe pdf) | ISBN 9781119890935 (epub)Subjects: LCSH: Sustainable forestry. | Forest ecology. | Forest management–Environmental aspects.Classification: LCC SD387.S87 E24 2024 (print) | LCC SD387.S87 (ebook) | DDC 634.9/2–dc23/eng/20230825LC record available at https://lccn.loc.gov/2023023190LC ebook record available at https://lccn.loc.gov/2023023191
Cover Design: WileyCover Image: Courtesy of Lukas Kopacki; Brian J. Palik; Douglas Kastendick; Anthony W. D’Amato
List of Contributors
William J. BeeseVancouver Island University (Retired) Nanaimo, BC, Canada
John‐Pascal BerrillCal Poly Humboldt, Arcata, CA, USA
Derek J. ChurchillForest Resilience Division, Washington Department of Natural Resources, Olympia, WA, USA
Philip G. ComeauDepartment of Renewable Resources University of Alberta, Edmonton, AB, Canada
Justin S. CrotteauUSDA Forest Service Rocky Mountain Research Station, Missoula, MT, USA
Miranda T. CurzonDepartment of Natural Resource Ecology and Management, Iowa State University Ames, IA, USA
Anthony W. D’AmatoRubenstein School of Environment and Natural Resources, University of Vermont Burlington, VT, USA
Robert L. DealUSDA Forest Service Pacific Northwest Research Station (Retired), Portland, OR, USA
Daniel C. DeyNorthern Research Station, USDA Forest Service, Columbia, MO, USA
Pablo J. DonosoFacultad de Ciencias Forestales y Recursos Naturales, Instituto de Bosques y Sociedad, Universidad Austral de Chile Valdivia, Chile
Daniel DumaisDirection de la recherche forestière Ministère des Ressources naturelles et des Forêts du Québec, Canada
Jodi A. ForresterDepartment of Forestry and Environmental Resources, North Carolina State University Raleigh, NC, USA
Jerry F. FranklinSchool of Environmental and Forest Sciences University of Washington, Seattle, WA, USA
Miguel Montoro GironaGroupe de Recherche en Écologie de la MRC Abitbi (GREMA), Institute of Forest Research, Université du Québec en Abitibi‐Témiscamingue, Amos, Quebec, Canada
J. Davis GoodeDepartment of Geography and the Environment, University of Alabama Tuscaloosa, AL, USA
Constance A. HarringtonHarrington, USDA Forest Service Pacific Northwest Research Station (Emeritus) Olympia, WA, USA
Justin L. HartDepartment of Geography and the Environment, University of Alabama Tuscaloosa, AL, USA
Steven B. JackBoggy Slough Conservation Area T.L.L. Temple Foundation, Lufkin, TX, USA
John M. KabrickNorthern Research Station, USDA Forest Service, Columbia, MO, USA
Tara L. KeyserUSDA Forest Service, Southern Research Station, Asheville, NC, USA
Benjamin O. KnappSchool of Natural Resources, University of Missouri, Columbia, MO, USA
Randy K. KolkaUSDA Forest Service, Northern Research Station, Grand Rapids, MN, USA
Timo KuuluvainenDepartment of Forest Sciences, University of Helsinki, Helsinki, Finland
S. Ellen MacDonaldDepartment of Renewable Resources University of Alberta, Edmonton AB, Canada
Andrew J. LarsonDepartment of Forest Management University of Montana, Missoula, MT, USA
David B. LindenmayerFenner School of Environment and Society Australian National University, Canberra ACT, Australia
Maxence MartinUniversidad de Huelva dr. Cantero Cuadrado 6 Huelva 21004, Spain
R. Kevin McIntyreJones Center at Ichauway, Newton, GA, USA
Thomas A. NagelDepartment of Forestry and Renewable Forest Resources, University of Ljubljana, Ljubljana Slovenia
Kellen N. NelsonUSDA Forest Service Pacific Northwest Research Station, Juneau, AK, USA
Charles A. NockDepartment of Renewable Resources University of Alberta, Edmonton, AB, Canada
Martin Alcala PajaresUniversidad de Huelva dr. Cantero Cuadrado 6 Huelva 21004, Spain
Brian J. PalikUSDA Forest Service, Northern Research Station, Grand Rapids, MN, USA
Brad D. PinnoDepartment of Renewable Resources University of Alberta, Edmonton, AB, Canada
Timo PukkalaForest Science and Technology Centre of Catalonia, Solsona, Spain
Patricia RaymondDirection de la recherche forestière, Ministère des Ressources naturelles et des Forêts du Québec, Canada
Laura F. ReulingDepartment of Forest Resources, University of Minnesota, Twin Cities MN, USA
Dušan RoženbergarDepartment of Forestry and Renewable Forest Resources, University of Ljubljana, Ljubljana Slovenia
David K. SchnakeDepartment of Forestry and Environmental Resources, North Carolina State University Raleigh, NC, USA
Robert S. SeymourSchool of Forest Resources, University of Maine, Orono, ME, USA
Robert A. SlesakUSDA Forest Service, Pacific Northwest Research Station, Olympia, WA, USA
Daniel P. SotoDepartment of Natural Sciences and TechnologyUniversity of AysenCoyhaique, Chile
Miroslav SvobodaDepartment of Forest Ecology, Faculty of Forestry and Wood Sciences, Czech University of Life Sciences Prague, Prague Czech Republic
Lucie VítkováDepartment of Forest Ecology, Faculty of Forestry and Wood Sciences, Czech University of Life Sciences Prague, Prague Czech Republic
Stephanie J. WessellNorthwest Oregon District Office USDI Bureau of Land Management Salem, OR, USA
Abraham WheelerOR/WA State Office, USDI Bureau of Land Management, Portland, OR, USA
Marcella A. Windmuller‐CampioneDepartment of Forest Resources, University of Minnesota, Twin Cities MN, USA
Robert A. YorkDepartment of Environmental Science Policy and Management, University of California Berkeley, CA, USA
Preface
In a nutshell, ecological silviculture is the toolbox to manage forests as ecosystems, based on emulation of natural models of disturbance and development. It follows that an ecological silvicultural system is the long‐term sequence of treatments for managing composition and structure of a forest, as informed by natural disturbance and development. One could say that ecological silviculture is guilty of putting the forest first, rather than focusing one or a few tree species of commercial value, which can be the focus of timber‐focused silviculture. This is not to say that ecological silviculture does not include an objective of managing for timber and commodity output. It does and, in fact, it could not be considered for wide application if there was not a path for profitable forest management as an objective. The distinction, from timber‐focused silviculture, is that sustainability of non‐commodity goods and services is given high priority as an objective. Moreover, the conceptual framework for devising ecological silvicultural systems is that nature knows best, rather than building on agronomic models like classic silviculture. The former involves understanding natural disturbance dynamics for a forest and how that forest develops over time to become a structurally complex and often species rich ecosystem, with a goal of reducing, as much as feasible, the disparity between a natural ecosystem and its managed counterpart. As you will learn, this attempt to better emulate natural forest development is important even in the face of unprecedented global changes, including climate change and invasive pests.
You will learn that not all contributors to this book have the same interpretation of a natural model for forests, nor are their formulations of ecological silvicultural systems the same. In fact, the silviculture presented in this text reflects highly diverse views about how forests work naturally and how silviculture can be used to better emulate natural processes. The diversity reflects geography, with contributors working in forests across the United States, in eastern, central, and western Canada; in Chile and Australia; and several forests in Europe. It also reflects differing views about the degree to which a natural model can be used in silviculture. Embrace this diversity, as it captures the most innovative thinking on the topic of ecological silviculture from the world’s most innovative thinkers in the field. Importantly, all contributors do share one central goal, that of presenting silvicultural systems for forests that better sustain ecosystems broadly, so as to provide the full array of services people expect from forests.
Brian J. Palik and Anthony W. D’Amato
Acknowledgments
Many influential thinkers have shaped our ideas about forest ecology and silviculture, through their writings and mentorship, but more often through thoughtful discussions. In fact, several of these people have contributed to this book, while the influence of others is reflected in the chapters we authored. Topping our list is Dr. Jerry Franklin, whose thinking on the topic of managing forests ecologically predated most, if not all western scientists. Without his mentorship and inspiration, we would have very different careers. We thank others, in no particular order, including Robert (Bob) Mitchell, Bob Seymour, Mac Hunter, Kurt Pregitzer, Shawn Fraver, John Bradford, Craig Lorimer, Ellen Macdonald, Jim Long, Patricia Raymond, Dan Kneeshaw, Linda Nagel, David Foster, Klaus Puettmann, Steve Jack, Bill Leak, Steve Bédard, Kevin Evans, Paul Catanzaro, David Lindenmayer, Mariko Yamasaki, Mike Snyder, and David Kittredge. We also acknowledge the generations of Indigenous peoples and the historically overlooked models of ecological silviculture they advanced and continue to practice today. These contributions far predate the formalization of silviculture by Western scientists and foresters and deserve a long overdue acknowledgment for providing critical models to emulate as we grapple with how best to steward forests into the future. Finally, our home institutions provided the time and financial support needed to complete this project including the USDA Forests Service‐Northern Research Station (Palik) and The University of Vermont‐Rubenstein School of Environment and Natural Resources (D’Amato). We thank them for this support.
Brian J. Palik and Anthony W. D’Amato
1The Context of Ecological Silviculture
Brian J. Palik1 and Anthony W. D’Amato2
1 USDA Forest Service, Northern Research Station, Grand Rapids, MN, USA
2 Rubenstein School of Environment and Natural Resources, University of Vermont, Burlington, VT, USA
1.1 What Is Ecological Silviculture?
In forestry, the tools to carry out on‐the‐ground management are found in the toolbox of silviculture, that is, the part of forestry that deals with the development and care of forests. This development and care can be all encompassing, including establishment, growth, composition, health, and quality of trees and stands to meet the diverse needs of society. The planned program of all these activities, spanning the entire life of a forest stand, is termed a silvicultural system.
Ostensibly, such a definition for silviculture would seem to recognize most forests, outside of plantations, as natural ecosystems and that the tools to manage these ecosystems would be based on ecological principles. In reality, classical silviculture is largely based on principles of production agriculture, more so than the ecology of natural forests [1]. The outcome of the long‐term application of an agricultural model to managed forest is near global‐wide simplification of structure and composition [2], as well as a reduced ability to adapt to unexpected and novel threats [3].
This is where ecological silviculture comes in, which we define as an approach for managing forests, including trees, associated organisms, and ecological functions, based on emulation of natural models of development [2]. There are other closely aligned approaches that also are ecological that have similar aims, such as close‐to‐nature forestry (e.g. [4]). An explicit goal of ecological silviculture and allied approaches is to manage forests in ways that reduce the disparity between natural forests and their managed counterparts in terms of composition, structure, and function. Recognizing that this disparity cannot be eliminated in managed forests, particularly those where timber resources are highly valued, ecological silviculture still rests on the premise that managers can get closer to the natural model than classical silvicultural has allowed. Let us look at why this might be, by contrasting some of the main differences between the two approaches.
1.2 How Does Ecological Silviculture Differ from Classical Commodity‐Focused Silviculture?
The central emphasis of ecological silviculture is on maintaining the full array of structures, functions, and species found in a healthy natural forest ecosystem [2]. To achieve this goal, ecological silviculture builds from an understanding of natural disturbances and forest development to craft silvicultural systems that generate and maintain complexity and heterogeneity in ecosystem attributes. This often includes the application of regeneration harvests patterned after the prevailing natural disturbance regime for an ecosystem, including their scale, severity, and frequency. In addition, the legacies of these disturbances, namely surviving trees, and coarse woody material, are accounted for by placing an equal emphasis on what is left behind relative to what is removed at each silvicultural intervention over the course of the silvicultural system. Although economic objectives are still a priority with ecological silviculture, those associated with ecosystem diversity and resilience are given high priority in the design and implementation of ecological silvicultural systems.
In contrast, commodity‐focused silviculture emphasizes the “forest crop” and is correspondingly concerned with silvicultural regimes that generate forest conditions to optimize growth and development of economically desirable species and tree forms. Silviculture treatments under this approach are largely based on agronomic models with a corresponding emphasis on simplifying and homogenizing forest‐wide structure (e.g. spacing) and composition (i.e. primarily commercial tree species) to maximize the area occupied by economically desirable trees and to enhance the efficiency of harvest operations. Not surprisingly, the timing, frequency, and severity of silvicultural treatments are largely governed by economic criteria, including maximizing net present value, and avoiding risk of crop‐tree loss to damaging agents [5]. Forests managed under this approach can satisfy noneconomic objectives to a degree [6]; however, achievement of economic objectives is the central priority under timber‐focused regimes.
1.3 Why Is Ecological Silviculture Needed?
To appreciate the need for ecological silviculture, consider how the forces shaping forest management have changed over the last 70 years. First, globally, it is estimated that there are 4.0 bha of forest, including 0.3 bha of plantations and 3.7 bha of natural‐origin forests; moreover, of the latter, 0.65 bha are legally protected reserves [7]. Generally, plantations are managed intensively for wood, such that ecological benefits are marginalized, while reserves usually exclude harvesting. This leaves about 3 bha of natural‐origin forests where multiple environmental, economic, and social objectives are pursued [8] and, for the portion of this forest that is managed, ecological silviculture may be the appropriate tool for meeting diverse objectives.
In fact, the drivers of policy and practice across the global forest have changed fundamentally to be more ecological [2]. For example, conservation stewards, such as The Nature Conservancy, have emerged as key players in the forest management world, with their goals being overtly ecological. Also, the objectives of traditional forest stewards, e.g. United States National Forests, have evolved to focus on sustaining whole ecosystems. Additionally, third‐party certification, as well as best management practices (BMP’s), have led forest stewards to adopt ecological approaches for silviculture. Many largely unprecedented health threats facing forests, including climate change, catastrophic wildfires, and invasive species, require silviculture that restores the structural and functional integrity of forests to better position them to adapt to uncertainty [9]. Finally, the vast increase in our understanding of forests – how they are structured, how they function, and how they are connected across the landscape – argues for a different kind of silviculture, one that focuses on forests as ecosystems, not agricultural ecosystems.
1.4 What Are the Foundational Concepts of Ecological Silviculture?
While the definition of ecological silviculture may vary a bit among stakeholders, all are based on an understanding and modeling of natural disturbance and forest development. For silvicultural application, such a model begins with canopy disturbance and proceeds through stages that reflect structural maturation. The model may include a preforest stage, followed by young, mature, and old forest stages (Box 1.1). The model may apply to whole‐stands or patches within stands. As you will learn in the chapters that follow, ecological silvicultural systems often emulate this developmental model and are catered to the ecological and socioeconomic contexts of the ecosystem being managed.
Box 1.1 Some Concepts and Terms Associated with Ecological Silviculture
Biological legacies
: biological legacies are healthy trees, decadent trees, large deadwood, and derivatives of dead trees, e.g. tip‐up mounds, and pre‐disturbance vegetation (advance regeneration, understory plants) that survive from the previous forest into the new forest after disturbance.
Deadwood:
dead trees, including snags and downed wood, and tree components (branches, roots).
Forest developmental stages
Disturbance and legacy creation:
a disturbance that kills trees and leaves a legacy of organisms and structures from the pre‐disturbance forest.
Preforest
: a period when herbs and shrubs dominate growing space and tree abundance is not enough to dominate the site.
Young forest
: establishment of new cohort trees of relatively uniform size, along with large legacy trees; density‐dependent mortality is a dominant process in this stage.
Mature forest:
new cohort trees dominate; mortality shifts to density‐independent agents; advance regeneration of shade‐tolerant trees are released and species of lesser tolerance may establish in canopy gaps; spatial heterogeneity of structure increases; new deadwood accumulates.
Old forest:
a diverse mix of live and dead trees of varying size and condition; high levels of spatial heterogeneity; increasing decline and mortality of trees from exogenous agents; significant inputs of large deadwood.
Recovery period
: the time between regeneration harvests of sufficient duration to allow for development of mature forest structures.
Retention tree:
a tree retained during a regeneration harvest to live out its natural lifespan so as to provide mature forest structural elements and associated functions.
Structural complexity
: abundance, size, conditions, and degree of heterogeneity in living and dead components in a forest.
Variable retention harvesting
:
retention of living trees and deadwood at harvest in a range of spatial patterns
(dispersed and aggregated) and
abundances; includes retention of species or functional groups, e.g. conifers or hardwoods, and can occur stand‐wide or at gap‐scales depending on natural developmental model being emulated.
Variable‐density thinning:
silvicultural strategy that varies the density of removal across a stand, including gaps, standard thinning, and no removal; accelerates the development of complexity and heterogeneity. Although termed a “thinning,” this approach includes deliberate consideration for regenerating new cohorts in gaps, so it can also be considered as a regeneration method.
Another commonality of ecological silvicultural systems is that they address several foundational principles derived from a natural model. We have discussed these principles in detail elsewhere [2, 10], which include continuity, complexity/diversity, timing, and context. Here we provide a brief review, along with some definitions of terms associated with the principles (Box 1.1).
Continuity is the provisioning of structure, biota, and function from a pre‐ to post‐disturbance forest. The currency of continuity are biological legacies, especially retention trees and large deadwood, and the principle is often addressed using gap‐scale or forest‐wide variable retention harvesting (see Box 1.2) during regeneration harvests.
Box 1.2 Clarifying and Advancing Ecological Silviculture Terminology: Variable Retention Harvests and Variable‐Density Thinning
When the important task of inventing the solution has proceeded far enough, the less important task of attaching a name to it can be taken. Standard terminology should be used to the extent of its limited capacity for providing information in terms meaningful to all foresters and then supplemented with additional, detailed information that is usually necessary.
—David Smith [11]/John Wiley & Sons.
The use of a common and standard terminology has been a central aspect of the discipline of silviculture with the core intent of minimizing confusion over intended prescription outcomes and maintaining professionalism and consistency of communication in the field. The silvicultural terms and practices used in North America and many other regions generally owe their origin to European silviculture methods, which were primarily designed to address the predominant socioecological conditions in Europe during the nineteenth and twentieth centuries [1]. These terms and practices were codified into North American professional standards, texts, and curricula in the early twentieth century [12, 13] and have served as the cornerstone of silviculture ever since. It is noteworthy that Indigenous models of forest stewardship actually predated the formalization and organization of the American forestry profession [14], yet these models were largely ignored by early, European‐trained forest scientists and foresters and have only recently been recognized by non‐tribal institutions as powerful models for informing ecological silviculture (e.g. [15, 16]).
Given the general adherence of North American silviculturists to European terminology and approaches, a long‐standing, albeit unfounded, criticism of ecological silviculture has been that it largely reinvented terms for practices that already have names in the traditional silviculture vernacular. This is particularly true for two of the most commonly applied elements of ecological silvicultural systems, variable retention harvests (VRH) and variable density thinning (VDT). For both of these practices, criticism has stemmed from their similarity to existing regeneration methods that include “reserves” or that apply multi‐cohort systems that work from and maintain spatial heterogeneity in structure and composition in a forest over time (e.g. group selection and some irregular shelterwood systems). The outcomes of these existing methods may resemble those following VRH or VDT at different stages of implementation; however, there are key differences in the intent of historical silvicultural methods that prevent making them synonymous with certain ecological silviculture terms and approaches.
In an attempt to move terminology forward, particularly given how widespread the use of VRH and VDT has become (as evidenced in the chapters that follow), it is worth defining and clarifying the intent of these ecological silvicultural methods. Our hope is to introduce consistency in communicating the intent and application of these practices and to move beyond forcing the use of traditional terms in cases where they do not make sense nor convey silvicultural intent. Importantly, the use of standard and historical terminology still is a key aspect of any silvicultural application, whether it is ecological or not. Nevertheless, we should strive as a profession to allow for evolution of historical and new terms to allow for operationalization of strategies that match new and emerging objectives in a twenty‐first century context.
Variable Retention Harvests
VRH is a two‐aged regeneration method that emphasizes the permanent retention of mature canopy trees, as well as other important structural legacies, such as snags and downed logs at the time of regeneration harvest. VRH was first popularized in the Pacific Northwest region of the United States during the 1990s in response to social and ecological concerns surrounding the widespread use of clear‐cutting methods [17], with their use expanding globally over the past two decades into many regions where clear‐cutting‐based methods historically prevailed [18]. In practice, this method encapsulates the ecological silviculture principle of continuity by ensuring structural, functional, and compositional elements from the preharvest forest are carried forward into the new, regenerating stand.
The use of the term “variable” to describe these systems reflects the need to vary the amount and distribution of retained trees depending on management objectives and ecological conditions, with this flexibility contributing to the wide range of global ecosystems and ownerships now applying this approach. In regions where there is a longer history and greater experience with VRH, such as British Columbia, Canada, fairly specific guidelines exist surrounding levels of retention, and spatial patterns of retention when applying VRH as an integrated silvicultural system for achieving ecological objectives [19]. For other regions and forest types, less guidance may exist and the flexibility of VRH should be utilized to determine the retention levels and patterns necessary to achieve ecological goals over time. To this end, although originally termed a “harvest system,” VRH is better thought of as a regeneration method, so the seedbed conditions and resource environments required by the desired species on a site are a critical consideration in the design of VRH, with differing patterns of retention often used to accommodate species with varying tolerance [20]. Unfortunately, applications of VRH have led to a common misconception that solely retaining trees at the time of harvest is all that ecological silviculture entails [10]; however, true ecological silvicultural systems often use VRH as the regeneration method occurring at the Disturbance and Legacy Creation stage of a given system. As with other silvicultural systems, subsequent intermediate treatments, such as release treatments and thinning, are applied over time to enhance ecological conditions and future economic outputs and achieve long‐term desired future ecological conditions (Figure 1.1).
Existing two‐aged regeneration methods, such as clear‐cutting, seed‐tree, and shelterwood, with reserves certainly have similarities to VRH given these methods include the retention of some mature trees beyond 20% of the rotation age of the new regenerating cohort (the definition of with reserves systems). Nevertheless, a key and important distinction between VRH and these older methods is intent. In particular, the historical intent of retaining “reserve trees” largely revolved around allowing canopy trees to grow to larger, more economically valuable sizes before their ultimate harvest [13]. Modern silviculture texts certainly acknowledge that we now also retain “reserves” for many ecological and cultural values [21]; however, future economic returns from these reserve trees remains an objective linked to this terminology, making it incongruous with the intent of VRH.
Figure 1.1 Variable retention harvest in red pine‐dominated forests in north‐central Minnesota, USA. Left photo represents disturbance/legacy creation stage with right hand photo taken from same site during early portion of the young forest stage. Release treatments were applied to site during young forest stage to enhance development of natural and artificial regeneration established on site.
Of note, permanent retention of legacy trees is certainly not restricted to VRH, as gap‐level retention of legacy trees is a common feature of ecological silviculture systems for ecosystems dominated by gap and mesoscale‐disturbance regimes. As with VRH, simply modifying the regeneration methods used for these forests to include “reserves” does not fully convey silvicultural intent given the primary objective for retention is for those trees to live out their natural lifespan. As such, adding modifiers such as “with permanent legacy retention” to regeneration methods, such as group selection or expanding gap irregular shelterwoods, maybe a more effective way to communicate these methods going forward to avoid confusion with traditional strategies developed during a time (i.e. eighteenth and nineteenth century) where permanent retention was not acceptable from a socioeconomic standpoint.
Variable‐Density Thinning
VDT is a harvesting method in which the removal of trees is varied spatially across a stand or management unit to increase heterogeneity in horizontal and vertical structure. As with VRH, VDT developed in the Pacific Northwest region of the United States, with the intent of restoring the spatial variability in canopy tree densities and age classes that are a common attribute of natural forests around the globe [22]. This approach reflects the ecological silviculture principle of complexity and is generally applied to forests in the late young forest or mature forest stages of stand development to accelerate heterogeneity in forest conditions. To this end, VDT is a common component of ecological silvicultural systems applied to second‐growth forests homogenized by past management practices (e.g., plantations). In its application, VDT includes the creation of a combination of canopy gaps and thinned areas, as well as designation of permanent, unharvested areas as patch reserves (i.e. groups of legacy trees) (Figure 1.2). This pattern of harvesting and retention creates and reinforces structural and compositional conditions found in the old forest stage of development, including canopy gaps, lower density areas with larger diameter trees, and dense vegetation, all‐natural outcomes of a long‐term history of gap‐phase disturbance and tree maturation.
Figure 1.2 Variable density thinning (VDT) within 6‐ha harvest unit on the Nulhegan Basin of the Silvio Conte National Wildlife Refuge in Brunswick, VT, USA. Overarching goal of VDT is to meet objectives surrounding increasing ecological complexity in spruce‐fir forests simplified by past land use to enhance habitat conditions for priority bird species. (a) Second‐growth spruce‐fir forest homogenized by historic, intensive management; (b) 0.1 ha gaps for recruiting new age‐class and increasing compositional diversity; (c) thinned matrix conditions for accelerating large‐tree development; and (d) patch reserves (i.e. skips) to protect unique ecological features and maintain areas of high stem density and canopy cover.
A primary reason for the widespread appeal of VDT is the relative simplicity with which it operationalizes and achieves desired ecological outcomes (e.g. [23]). In particular, tree marking focuses on identifying logical areas for gap creation (e.g. pockets of advance regeneration) and patch reserves or “skips” (e.g. rare plant communities, areas with high accumulations of deadwood) with thinning applied in matrix areas between these gap and anti‐gap elements to accelerate tree growth. Adaptations of this approach have been extended to frequent‐fire mixed conifer systems where widely spaced trees, canopy openings, and clumps of trees are created using the Individuals, Clumps, and Openings (ICO) approach [24]. As with VDT, the varying tree densities created by the ICO approach are intended to restore natural patterns of tree density, which in the case of frequent‐fire forests are often mosaics of large‐diameter individual trees, gaps, and tree clumps of different sizes.
An unfortunate aspect of VDT is its name, as this approach includes provisions for regeneration in the gap elements created. Thinning treatments in a traditional sense are focused on improving the growth and quality of existing trees on a site with no intent to regenerate new cohorts. The use of “thinning” in describing VDT has created confusion over its intent and where it fits with regard to existing silvicultural treatments (i.e. is it an intermediate treatment or regeneration method?). Given the inclusion of regeneration as part of VDT, it is best classified as a regeneration method with aspects similar to hybrid single‐tree and group selection and expanding gap and continuous cover irregular shelterwoods. A key difference is that VDT is meant to restore a spatial structure that includes stand areas that will never be harvested (skips). In addition, VDT is best viewed in many applications as a transformative silviculture treatment moving simplified, even‐aged stands into more complex, multi‐aged conditions [25]. As such, future entries following the application of VDT may take the form of the aforementioned selection and irregular shelterwood methods by either expanding gaps created by VDT or applying single‐tree and group removals in thinned matrix areas to further emulate natural developmental models for a given forest. In short, it is an unfortunate name but has been widely demonstrated as a highly valuable tool for conveying and achieving ecological silviculture objectives, so we are sticking with it.
Complexity/diversity addresses the need to create and maintain structural complexity and species diversity in managed stands. Often, application of this principle takes the form of restoration, particularly in stands lacking complexity and tree diversity. Some of the tools for addressing complexity/diversity include variable‐density thinning (VDT) (see Box 1.2), decadence and deadwood creation, and tree enrichment.
Timing is the application of silvicultural interventions at ecologically appropriate intervals, especially the time necessary for recovery and development of structure after a major disturbance. It also reflects the need to allow appropriate time intervals between intermediate treatments, such as thinning.
Finally, context underscores the importance of implementing silviculture with the landscape perspective in mind. Context recognizes that stand‐level actions accumulate to influence the structure and function of landscapes.
1.5 What to Expect from the Chapters that Follow?
The chapters that follow present ecological silvicultural systems for various forest types in North American, as well as examples from Europe, South American, and Australia. These systems have been conceived by innovative researchers and forest stewards who often have been studying their forests for decades. The chapters will vary a bit, depending on the forest type, but all will have some commonalities. Each will present (i) the natural history of the forest, (ii) a summary of the forest’s cultural, economic, and ecological importance, (iii) the natural dynamics model for the ecosystem, (iv) a review of the traditional silvicultural system, (v) a presentation of an ecological silvicultural system and a reflection on how the latter reduces the disparity between the natural and management models, and finally, (vi) a consideration of ecological silviculture in the context of climate change.
Another common thread is that all the authors recognize that for their forest, a tweaking of classical, often timber‐focused, silviculture is not sufficient to meet the needs of forest management broadly in the twenty‐first century. Moreover, the contributors recognize that a simple bifurcation of the forest landscape into production and protected forests [26] is not sufficient to sustain natural forest ecosystems broadly; that is, for much of the global forest ecological silvicultural approaches may better sustain the diverse suite of ecosystem services society expects [27], even under changing climate and disturbance regimes [9]. Providing the tools to meet these expectations in diverse forests is what you can expect from this book.
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