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Wetland Resources Forested Northern Wetlands of North America, T.E. Dahl and S.C. Zoltai Status and Trends of Forested Wetlands in the Northern United States, W.E. Frayer Forested Mires as a Renewable Resource-Toward a Sustainable Forestry Practice, J. Paivanen Policy for Conservation of the Functions and Values of Forested Wetlands, C.D.A. Rubec A Comparison of Wetland Mapping Using SPOT Satellite Imagery and National Wetland Inventory Data for a Watershed in Northern Michigan, T.A. Forgette and J.A. Shuey Ecology and Vegetation Stand Structure, Dynamics, and Diversity of Virgin Forests on Northern Peatlands, Y. Norokorpi, E. Lahde, O. Laiho, and T. Saksa Relationships between Groundwater Characteristics, Vegetation, and Peatland Type in the Hiawatha National Forest, Michigan, G.M. Kudray and M.R. Gale Late Holocene Paleoecological Reconstruction of a Coastal Peat Bog along the St. Lawrence Maritime Estuary, M. Garneau Changes in Species Diversity in Peatlands Drained for Forestry, H. Vasander, R. Laiho, and J. Laine Undergrowth as a Regeneration Potential on Finnish Peatlands, O. Laiho, E. Lahde, Y. Norokorpi, and T. Saksa Plant Reintroduction on a Harvested Peat Bog, F. Quinty and L. Rochefort A Ground-Penetrating Radar Study of Peat Landforms in the Discontinuous Permafrost Zone Near Fort Simpson, Northwest Territories, Canada, I.M. Kettles and S.D. Robinson Hydrology and Biogeochemistry Hydrological Processes of Natural, Northern Forested Wetlands, E.S. Verry Hydrology of Drained Forested Wetlands, S.E. Vompersky and A.A. Sirin Hydrological-Chemical Interactions in Headwater Forest Wetlands, A.R. Hill and K.J. Devito Application of Modeling Methods to Study Water Budgets in Forested Peatlands, J. Ruseckas Water Table Fluctuations Following Clearcutting and Thinning on Wally Creek Wetlands, V. Roy, J.K. Jeglum, and A.P. Plamondon Effects of Engineered Drainage on Water Tables and Peat Subsidence in an Alberta Treed Fen, G.R. Hillman Wetland Effects on Hydrological and Water Quality Characteristics of a Mid-Michigan River System, T.M. Tompkins, W.W. Whipps, L.J. Manor, C.W. Radcliffe, D.M. Majewski, and M.J. Wiley Relationships between Groundwater Level and Temperature in Peat, H. Hokka, T. Pentilla, and M. Siipola Factors Affecting Sediment Accumulation in Sedimentation Ponds, S. Joensuu The Dynamics of Peat Accumulation by Mires of Northern Eurasia During the Last 3000 Years, V.A. Klimanov and A.A. Sirin The Effect of Peatland Forestry on Fluxes of Carbon Dioxide, Methane, and Nitrous Oxide, H. Nykanen, J. Silvola, J. Alm, and P.J. Martikainen Nutrient Removals Associated with Harvesting Peatland Black Spruce Forest, Y. Teng, N.W. Foster, P. Hazlett, and I.K. Morrison The Effects and Fate of Inorganic Nitrogen Inputs to Oligotrophic Peat Soils, B.L. Williams and D.J. Silcock Wetland Management Forest Management Impacts on Undrained Peatlands in North America, D.F. Grigal and K.N. Brooks Peatland Forestry in Finland: Problems and Possibilities from the Nutritional Point of View, S. Kaunisto Forestry Best Management Practices for Wetlands in Minnesota, M.J. Phillips Effects of Forest Management on Wetland Functions in a Sub-Boreal Swamp, C.C. Trettin, M.F. Jurgensen, J.W. McLaughlin, and M.R. Gale Mound Characteristics Affect Growth and Survival of Norway Spruce Seedlings, L. Akerstrom and B. Hanell Greenhouse Impact of a Mire after Drainage for Forestry, J. Laine, K. Minkkinen, J. Sinisalo, I. Savolainen, and P.J. Martikainen Response of Stand Growth and Water Table Level to Maintenance of Ditch Networks within Forest Drainage Areas, E. Ahti and J. Paivanen Comparative Growth of Peatland, Upland, and a Superior Black Spruce Stand in Ontario, B. Payandeh, V.F. Haavisto, and P. Papadopol Index

I. PEOPLE AND FORESTS: WHY THE SCIENCE OF FOREST ECOLOGY DEVELOPED. 1. Sustainability of Forest Ecosystems: The Problem of Human Population Growth. 2. Development of Forestry and Forest Ecology. II. ECOSYSTEM AS THE BASIC UNIT OF FOREST ECOLOGY. 3. Ecology and the Ecosystem Concept. 4. Production Ecology: The Transfer and Storage of Energy in Ecosystems. 5. Biogeochemistry: Cycling of Nutrients in Ecosystems. III. ECOLOGICAL DIVERSITY AND THE ECOLOGICAL STAGE: PHYSICAL DETERMINANTS OF THE ECOLOGICAL PLAY. 6. Ecosystem Classification: The Ecological Foundation for Sustainable Forest Management. 7. Ecological Role of Solar Radiation. 8. Temperature as an Ecological Factor. 9. Wind: Ecological Effects of Atmospheric Movements. 10. Water: The Material that Makes Life Possible. 11. Soil: The Least Renewable Physical Component of the Ecosystem. 12. Fire: A Pervasive and Powerful Environmental Factor. 13. Patterns of Biotic Communities along Environmental Gradients. IV. BIOLOGICAL DIVERSITY: POPULATION, COMMUNITY, AND GENETIC DETERMINANTS OF THE ECOLOGICAL PLAY. 14. Population Ecology: Study of the Abundance and Dynamics of Species Populations. 15. Community Ecology. 16. Genetic and Evolutionary Aspects of Ecosystems: Adaptation and Evolution.1 V. TEMPORAL DIVERSITY: THE ECOLOGICAL PLAY IN WHICH ALL ASPECTS OF ECOSYSTEMS CHANGE OVER TIME. 17. Ecological Succession: Processes of Change in Ecosystems.1 18. Understanding and Emulating Natural Forest Disturbance: A Template for the Management of Succession and Temporal Diversity? VI. SPATIAL DIVERSITY: THE LANDSCAPE REVISITED. 19. Ecosystem Management and Landscape Ecology - The Ultimate Focus in Forest Ecology. 20. Environmental Issues in Forestry: The Role of Ecology in the Management of the Ecological Play. VII. APPLICATION OF ECOLOGICAL KNOWLEDGE IN THE MANAGEMENT OF FOREST ECOSYSTEMS. 21. Models and Their Role in Ecology and Resource Management.1 22. Sustainability and Renewability of Natural Resources, and Implications for Forest Management. 23. Concluding Statement.

Part 1 Introduction: forests as a renewable resource forestry in Europe susceptibility of plantation monocultures to insect outbreaks characteristics of insect outbreaks. Part 2 Forests as a habitat for insects: the community of insects on trees climate and weather in the ecology of forest insects biotic factors in the ecology of forest insects. Part 3 Trees as a source of food for insects: nutritional requirements of herbivorous insects nutrient content of trees in relation to structure and function food quality and plant defence insect life cycles in relation to the quantity and quality of food host stress and food quality trees and insect population dynamics implications of insect and tree interactions for forest management. Part 4 The nature of forest insect problems: pest problems in relation to the growing forest special plantations and urban pest problems interactions with other insects and disease organisms the impact of insects on forests and forest trees. Part 5 Forest practices: accidental introduction of pests planning of forestry plantations the post-planning stage - silvicultural techniques for pest management forest diversity and pest outbreaks forest practices and integrated pest management. Part 6 Plant resistance: variation in trees and insects defining resistance resistance mechanisms detecting genetically determined resistance in trees breeding for increased pest resistance host resistance and IPM. Part 7 Biological control: the origin and development of biological control in forestry the potential for biological control in forestry the potential for biological control in forestry the characteristics and use of biological control agents the safety of biological control agents. Part 8 Insecticides: historical aspect of insecticide use the scale of control operations with insecticides insecticides and pest biology the impact of insecticides - pests, natural enemies and environment insecticide technology regulation of insecticide use the costs of insecticides and the economics of their use in forestry. Part 9 Behaviour-modifying chemicals: the role of chemicals in insect behaviour the characteristics of pheromones anti-feedants and repellents. Part 10 Integrated pest management: integrated pest management in forestry developing an integrated approach to forest insect control case histories of integrated pest management in forestry.

Contents: Contributors Acknowledgments Chapter 1 Oaks and Acorns as a Foundation for Ecosystem Management -William J. McShea and William M. Healy Part I Patterns and Processes of Oak Forests Chapter 2 Distribution and Abundance of Oaks in North America -William H. McWilliams, Renee O'Brien, Gordon C. Reese, and Karen L. Waddell Chapter 3 The Postglacial History of Oak Forests in Eastern North America -Marc D. Abrams Chapter 4 Fire History and Postsettlement Disturbance -Daniel Dey Chapter 5 The Ecological Basis for Oak Silviculture in Eastern North America -Daniel Dey Chapter 6 Native Diseases and Insects That Impact Oaks -Steven W. Oak Chapter 7 Gypsy Moths and Forest Dynamics -Joseph S. Elkinton, William M. Healy, Andrew M. Liebhold, and John P. Buonaccorsi Chapter 8 Dynamics of Old-Growth Oak Forests in the Eastern United States - Lee E. Frelich and Peter B. Reich Part II Ecology and Patterns of Acorns Chapter 9 The Behavioral Ecology of Masting in Oaks -Walter B. Koening and Johannes M. H. Knops Chapter 10 Dynamics of Acorn Production by Five Species of Southern Appalachian Oaks -Cathryn H. Greenberg and Bernard R. Parresol Chapter 11 Nutritional Value of Acorns for Wildlife -Roy L. Kirkpatrick and Peter J. Pekins Chapter 12 Acorn Dispersal by Birds and Mammals -Michael A. Steele and Peter D. Smallwood Chapter 13 Ecological Webs Involving Acorns and Mice: Basic Research and Its Management Implications -Richard S. Ostfeld Chapter 14: Acorns and White-Talied Deer: Interrelationships in Forest Ecosystems -George A. Feldhamer Chapter 15: Oak Trees, Acorns, and Bears -Michael R. Vaughan Chapter 16: Turkeys, Acorns, and Oaks -Davis E. Steffen, Nelson W. Lafon, and Gary W. Norman Chapter 17 Squirrels and Oaks -Christopher C. Smith and Martin A. Stapanian Part III Management of Oaks for Wildlife Chapter 18 Fire and Oak Management -David H. Van Lear and Patrick H. Brose Chapter 19 California's Oak Woodlands -Richard B. Standiford Chapter 20 Ecology and Management of Evergreen Oak Woodlands in Arizona and New Mexico -Peter F. Ffolliott Chapter 21 Managing Eastern Oak Forests for Wildlife -William M. Healy Chapter 22 Goals and Guidelines for Managing Oak Ecosystems for Wildlife -William M. Healy and William J. McShea References Index

Abstract How drought affects tree and stand growth is an old question, but is getting unprecedented relevance in view of climate change. Stress effects related to drought have been mostly studied at the individual tree level, mostly investigating dominant trees and using their responses as indicator for the impact at the stand level. However, findings at tree and stand level may differ, as the stand responses include interactions and feedbacks that may buffer or aggravate what is observed at the individual tree level. Here, we trace drought effects on growth and development from tree to the stand scale. Therefore, we analyse annually measured data from long-term experiments in temperate and Mediterranean forests. With this analysis, we aim to disclose how well results of dominant tree growth reflect stand-level behaviour, hypothesizing that drought resistance of dominant trees’ can strongly deviate from the overall sensitivity of the stand. First, we theoretically derive how drought responses at the stand level emerge from the tree-level behaviour, thereby considering that potential drought resistance of individual trees is modulated by acclimation and tree–tree interactions at the stand level and that the overall stress response at the stand level results from species-specific and size-dependent individual tree growth and mortality. Second, reviewing respective peer-reviewed literature (24 papers) and complementing findings by own measurements (22 experiments) from temperate and Mediterranean monospecific and mixed-species forests, we are able to reveal main causes for deviations of tree-level and stand-level findings regarding drought stress responses. Using a long-term experiment in Norway spruce ( Picea abies (L.) KARST.) and European beech ( Fagus sylvatica L.), we provide evidence that the species-dependent and size-dependent reactions matter and how the size–frequency distribution affects the scaling. We show by examples that tree-level derived results may overestimate growth losses by 25%. Third, we investigate the development of the growth dominance coefficient based on measurements gathered at the Bavarian forest climate stations. We show that drought changes stand biomass partitioning in favour of small trees, reduce social differentiation, and homogenize the vertical structure of forests. Finally, we discuss the drought-related consequences of the social class-specific growth reaction patterns for inventory and monitoring and highlight the importance of these findings for understanding site-specific stand dynamics, for forest modelling, and for silvicultural management.

This paper highlights the significance of Artificial Intelligence (AI) in the realm of drone applications in forestry. Drones have revolutionized various forest operations, and their role in mapping, monitoring, and inventory procedures is explored comprehensively. Leveraging advanced imaging technologies and data processing techniques, drones enable real-time tracking of changes in forested landscapes, facilitating effective monitoring of threats such as fire outbreaks and pest infestations. They expedite forest inventory by swiftly surveying large areas, providing precise data on tree species identification, size estimation, and health assessment, thus supporting informed decision-making and sustainable forest management practices. Moreover, drones contribute to tree planting, pruning, and harvesting, while monitoring reforestation efforts in real-time. Wildlife monitoring is also enhanced, aiding in the identification of conservation concerns and informing targeted conservation strategies. Drones offer a safer and more efficient alternative in search and rescue operations within dense forests, reducing response time and improving outcomes. Additionally, drones equipped with thermal cameras enable early detection of wildfires, enabling timely response, mitigation, and preservation efforts. The integration of AI and drones holds immense potential for enhancing forestry practices and contributing to sustainable land management. In the future explainable AI (XAI) improves trust and safety by providing transparency in decision-making, aiding in liability issues, and enabling precise operations. XAI facilitates better environmental monitoring and impact analysis, contributing to efficient forest management and preservation efforts. If a drone's AI can explain its actions, it will be easier to understand why it chose a particular path or action, which could inform safety procedures and improvements.

Remote sensing provides valuable insights into pressing environmental challenges and is a critical tool for driving solutions. In this Primer, we briefly introduce the important role of remote sensing in forest ecology and management, which includes applications as diverse as mapping the distribution of forest ecosystems and characterizing the three-dimensional structure of forests. We describe six key reasons why remote sensing has become an important data source and introduce the different types of sensors (e.g., multispectral and synthetic aperture radar) and platforms (e.g., unmanned aerial vehicles and satellites) that have been used for mapping a diversity of forest variables. The rapid advancement in remote-sensing technology, techniques, and platforms is likely to result in a greater democratization of remote-sensing data to support forest management and conservation in parts of the world where environmental issues are the most urgent. Remote sensing provides valuable insights into pressing environmental challenges and is a critical tool for driving solutions. In this Primer, we briefly introduce the important role of remote sensing in forest ecology and management, which includes applications as diverse as mapping the distribution of forest ecosystems and characterizing the three-dimensional structure of forests. We describe six key reasons why remote sensing has become an important data source and introduce the different types of sensors (e.g., multispectral and synthetic aperture radar) and platforms (e.g., unmanned aerial vehicles and satellites) that have been used for mapping a diversity of forest variables. The rapid advancement in remote-sensing technology, techniques, and platforms is likely to result in a greater democratization of remote-sensing data to support forest management and conservation in parts of the world where environmental issues are the most urgent.

Landscape ecologists have been eager to make their research applicable to forest management. We examine how landscape ecology has contributed to shaping the way forest management is currently practiced. Landscape ecology research in forested ecosystems can be divided into two general areas: (1) the study of fragmentation issues, which focuses on the effects of forest fragmentation on species conservation; and (2) the development of landscape projection models, which focuses on patch dynamics and the effects of spatial arrangement of patches on ecosystem processes. Fragmentation issues have become priorities in the minds of forest managers, but research to date has over-emphasized the effects of landscape structure on species conservation. We suggest that the research focus should move toward the study of threshold effects of landscape change on the relative influence of habitat loss and habitat configuration on species conservation in forest-dominated landscapes. Landscape projection models are rapidly becoming important tools in forest management planning, and they hold great promise as a means to bring landscape ecologists and forest managers together. The ability to produce future landscapes under different management scenarios and to compare these to landscapes produced by natural disturbance regimes will help to focus both managers and scientists on understanding the key interactions among human activities, landscape features, and ecological processes.

Can land degraded by centuries of agriculture be restored to something approaching its original productivity and diversity? This book tells the story of fifty years of restoration and management of the forested landscape of the Savannah River Site, a 310-square-mile tract of land in the coastal plain of South Carolina that has been closed to the public for more than five decades. Ecology and Management of a Forested Landscape presents for the first time a complete synthesis and summary of information on the Savannah River Site, providing a detailed portrait of the plant and animal populations and communities on the site and the effects on them of fifty years of management practices. Contributors offer thirty-two chapters that describe the site's history, land management, physical environment, plant and animal communities, endangered species, and game species. Extensively illustrated with photos, maps, charts, and tables, the book provides a comprehensive overview of the forest management practices that can support long-term forest recovery and restoration of native habitats. It represents for natural resource managers a detailed case study in long-term land management, and provides scientists with an in-depth analysis of the natural history and physical and biological characteristics of a southeastern forested landscape.

Questions about the compatibility of forest harvesting practices and conservation of biological diversity are largely driven by concerns that habitat quality for many species may be degraded in intensively managed forest landscapes. We review the literature on relationships between common forest harvesting practices and the distribution and abundance of amphibians, a group that has attracted considerable attention in recent years because of their potential ecological importance in forest ecosystems and because of reports of widespread population declines. Clear-cut harvesting generally has negative short-term impacts on local amphibian populations, especially salamanders. An analysis of the results of 18 studies that examined the effects of clear-cutting on amphibians yielded a 3.5-fold median difference in abundance of amphibians on controls over clear-cuts. However, research on the influence of forest age suggests that the long-term effects of forest harvesting on amphibians are variable, and for many species these effects can be mitigated if regeneration practices leave adequate microhabitat structure intact. In contrast, long-term effects can be significant in forest plantations, which are often associated with intensive site preparations and stand management practices that modify levels of coarse woody debris and other microhabitats. Other forest practices reviewed for their effect on amphibians include prescribed fire, logging roads, and streamside harvesting. We discuss problems commonly encountered in the experimental design and measurement of forest amphibian populations, including a notable lack of pretreatment data, and outline several aspects of amphibian–forestry relationships in need of further research. Management recommendations relevant to conserving upland and riparian zone amphibian habitat during forest harvesting are offered.Key words: amphibians, clear-cutting, coarse woody debris, forest management, logging roads, plantations, prescribed fire, riparian, succession.

Introduction Classification and Inventory, J.P. Shepard, S.J. Brady, N.D. Cost, and C.G. Storrs Wetland Functions and Relations to Societal Values, M.M. Brinson and R.D. Rheinhardt Wetlands Regulation: Development and Current Practice, D.A. Gaddis and F.W. Cubbage General Functions of Southern Forested Wetlands Regional Climates, R.A. Muller and J.M. Grymes III Hydrology, T.M. Williams Soils and Landforms, J.A. Stanturf and S.H. Schoenholtz Biogeochemistry, B.G. Lockaby and M.R. Walbridge Adaptations of Plants to Flooding and Soil Waterlogging, M.R. McKevlin, D.D. Hook, and A.A. Rozelle Wildlife Communities, T.B. Wigley and R.A. Lancia Fishes, J.J. Hoover and K.J. Killgore Ecology and Management of Specific Wetland Types Southern Deepwater Swamps, W.H. Conner and M.A. Buford Major Alluvial Floodplains, R.C. Kellison, M.J. Young, R.R. Braham, and E.J. Jones Minor Alluvial Floodplains, J.D. Hodges Pocosins and Carolina Bays, R.R. Sharitz and C.A. Gresham Southern Mountain Fens, K.K. Moorhead and I.M. Rossell Pondcypress Swamps, K.C. Ewel Wet Flatwoods, W.R. Harms, W.M. Aust, and J.A. Burger Mangroves, R.R. Twilley Appendix References Index NTI Copy

Forest soils have characteristic properties that set them apart from the usual types of soils used for growing crops. Often rocky, of poor quality, and in mountainous terrain, forest soils are nevertheless the foundation of the entire forest ecosystem, supporting a diverse assemblage of plants and animals. They are often fragile soils, easily subject to erosion by road building or logging operation. A proper understanding of forest soils is an essential component of understanding forest ecology and maintaining the diversity and productivity of forested land. This new edition emphasizes the ecological aspects of forest soils. It is global in its scope, discussing soil types ranging from the tropical rainforest soils of Latin America to the boreal forest soils of Siberia. Separate chapters discuss the physical, chemical, and biological aspects of forest soils, with additional chapters on soil organic matter, roots, and biogeochemistry. It highlights the site specific factors that are important in each case and discusses practical management aspects including: nutrition management, thinning, site preparation techniques, soils for nursery and seed orchard operation, problem soils, atmospheric deposition of nutrients, soil acidity, and techniques for sustaining and improving long term soil productivity.

Tropical Forest Insect Pests, first published in 2007, promotes a better theoretical understanding of pest population dynamics, and causes of forest insect outbreaks in the tropics. Covering pests of both natural forests and plantations, it examines the diversity of tropical forest insects; their ecological functions; the concept of pests; and the incidence of pests in natural forests, plantations, and stored timber. General issues on which foresters and forest entomologists hold strong traditional views, such as the severity of pest incidence in plantations vs. natural forests, in plantations of exotics vs. indigenous tree species, and in monocultures vs. mixed plantations are discussed. The final section looks in detail at specific insect pests of the common plantation tree species across the tropics, with recommendations for their control. This is a comprehensive resource suitable for graduate students and researchers in forestry and tropical forest entomology, and for forest plantation managers in the tropics

Dead trees, both snags (standing dead trees) and logs (downed dead trees), are critical elements of healthy and productive forests. The ?Symposium on the Ecology and Management of Dead Wood in Western Forests? was convened to bring together forest researchers and managers to share the current state of knowledge relative to the values and interactions of dead wood to and in a functioning forest. Topics covered include the value of dead wood organisms in both terrestrial and aquatic habitats, the dynamics of dead wood, and ecological, industrial, and State and Federal land management agency perspectives. This information is immensely valuable to researchers and managers working with or managing dead wood in a variety of ecosystems

Invasions by nonindigenous forest insects can have spectacular effects on the biodiversity, ecology, and economy of affected areas. This introduction explores several critical issues that are generally relevant to invasions by forest insects to provide an extended background for this special issue of the Canadian Journal of Forest Research and highlights the key findings of the papers included in the issue. The topics covered address new information about (1) the role of cargo shipments as invasion pathways for the arrival of insects such as wood borers and bark beetles, (2) biogeographical effects that can influence the ecological and economic impact of insects feeding on exotic tree species, (3) the influence of biodiversity on impacts of forest insects and on the invasibility of ecosystem, and (4) recent advances in the detection, monitoring, and management of invasive species and native pests, including DNA barcoding for identification, the use of pheromones for monitoring and mating disruption, and biological control. These findings are likely to become even more important with elevated prevalence of invasions as a result of increasing global trade and international travel. Avenues of international communication and cooperation among scientists should be encouraged to enhance the sharing of information about biological invasions and to find solutions to this alarming problem.

The objective of this review is to give ecologists and policy makers a better understanding of forest carbon dynamics and recent policy and management activities in this arena. The ecology of forest carbon is well understood, but measurement and projection of carbon sequestration at small scales can be costly. Some forest management activities qualify as offsets in various carbon markets. To promote wider use, a system is needed that will provide inexpensive and standardized approaches to forest carbon accounting that are not prone to dishonest handling. The prospects are fairly promising for development of such a system, but first, technical and organizational constraints must be overcome. In contrast, the benefits – in terms of greenhouse‐gas reduction – of substituting wood for other building materials, and in displacing fossil fuel energy, could be realized immediately, if standards for calculations can be developed.

GENERAL ENTOMOLOGY. Introduction to Insects. Insect Structure and Function. Insect Classification. Insect Damage and Sign Categories. PRINCIPLES AND TECHNIQUES OF INTEGRATED PEST MANAGEMENT. Concepts of Integrated Pest Management. Population Dynamics of Forest Insects. Population Dynamics of Forest Trees in Relation to Phytophagous Insects. Principles of Population Modification and Regulation Using Artificial and Natural Agents. Impact Assessment. Monitoring Pest Populations and Forest Stands. INSECT FEEDING GROUPS. Defolating Insects. Sapsucking Insects and Mites. Terminal, Shoot, Twig, and Root Insects. Seed and Cone Insects. Phloem Boring Insects. Wood Boring Insects. Gall Makers. Arthropod Pests in Recreational Areas.

Mahogany (Swietenia macrophylla King) regenerates in areas of erosion on high terraces and in forest killed by flooding and deposition of alluvial sediments in the Chimanes Forest, Bolivia. These hydrological disturbances are patchy, and only one of five stands of mahogany that we inventoried was regenerating. Mahogany survives these disturbances significantly better than the common tree species. The long time between disturbances appears to favour late maturation. Mahogany trees allocate little photosynthates to reproduction until they are very large emergents, at least 80 cm in diameter. The episodic nature of the regeneration sites means that mahogany stands are composed of one or a few cohorts, which are vulnerable to overharvesting, particularly with the current use of a minimum cutting diameter to regulate harvest. The delayed onset of fecundity means that the small trees that escape harvest are not very fecund, resulting in minimal seed input to logged forest. Only 7–9% of the gaps created by logging contain natural regeneration after 20 + yr. A successful management plan for mahogany would entail a monocyclic harvest, with a rotation age of 100 + years, the estimated time that it takes for trees to achieve commercial size in natural forest. Since the number of seed trees that will be left is small, they should be concentrated in sites that are likely to be conducive to natural regeneration, such as near rivers and flood damaged forest. Seed production will be maximized for a given basal area (opportunity cost to loggers) if trees c. 110 cm dbh are selected as seed trees. The mahogany stocks in the Chimanes Forest are nearly exhausted, but the findings of this study could be used to help rebuild the mahogany populations, or to design management plans for the commercial species that have similar ecologies to mahogany.