Christoph Richter Wood Characteristics Description, Causes, Prevention, Impact on Use and Technological Adaptation Wood Characteristics Christoph R ichter Wood Characteristics Description, Causes, Prevention, Impact on Use and Technological Adaptation Dr. Christoph Richter Opitzer Weg 20 D-01737 Tharandt Germany Based on an updated translation of the original German 3rd edition of “Holzmerkmale” published by DRW-Verlag Weinbrenner, Leinfelden-Echterdingen (2010) ISBN 978-3-319-07421-4 ISBN 978-3-319-07422-1 (eBook) DOI 10.1007/978-3-319-07422-1 Springer Cham Heidelberg New York Dordrecht London Library of Congress Control Number: 2014955154 © Springer International Publishing Switzerland 2015 This work is subject to copyright. All rights are reserved by the Publisher, whether the whole or part of the material is concerned, specifi cally the rights of translation, reprinting, reuse of illustrations, recitation, broadcasting, reproduction on microfi lms or in any other physical way, and transmission or information storage and retrieval, electronic adaptation, computer software, or by similar or dissimilar methodology now known or hereafter developed. Exempted from this legal reservation are brief excerpts in connection with reviews or scholarly analysis or material supplied specifi cally for the purpose of being entered and executed on a computer system, for exclusive use by the purchaser of the work. Duplication of this publication or parts thereof is permitted only under the provisions of the Copyright Law of the Publisher’s location, in its current version, and permission for use must always be obtained from Springer. Permissions for use may be obtained through RightsLink at the Copyright Clearance Center. Violations are liable to prosecution under the respective Copyright Law. T he use of general descriptive names, registered names, trademarks, service marks, etc. in this publication does not imply, even in the absence of a specifi c statement, that such names are exempt from the relevant protective laws and regulations and therefore free for general use. While the advice and information in this book are believed to be true and accurate at the date of publication, neither the authors nor the editors nor the publisher can accept any legal responsibility for any errors or omissions that may be made. The publisher makes no warranty, express or implied, with respect to the material contained herein. Printed on acid-free paper Springer is part of Springer Science+Business Media (www.springer.com) Pref ace I t was 1995, in Dresden, Germany. I had stopped to linger over the display in a bookstore window. Suddenly, my eye caught the cover of a book with two pictures of spruce discs. My curiosity as a forester was piqued. The title read, “Holzfehler – Die Abweichungen von der normalen Beschaffenheit des Holzes” (“W ood Defects – D eviations from Standard Wood Structure ”), by Hermann Knuchel. I hesitated, because, as far as I knew, the book had been published last century, back in the 1930s. This had to be a new version of the 1934 edition. But why a reprint after 60 years of advances in wood research? Was there no more recent work of its kind? Investigating further I learned that since Knuchel’s work, many studies had indeed touched on the topic of “wood defects” with some surprising new fi ndings, but none provided such a systematic overview as Knuchel had in his day. “Wood defects” were either the subject of in- depth scientifi c research, carried out by specialists and published for specialists in scien- tifi c journals, or they appeared as subtopics in broader works on wood and wood processing, never as the main subject. Yet, the impact of “wood defects” on price and intended use plays just as important a role in the marketing and manufacturing of wood today as they did back in 1934. Since that memorable day in front of the bookstore window, I’ve been nurturing a dream to publish a revised study on “wood defects”; at the same time fully aware of the diffi cult balanc- ing act between covering the topic in suffi cient scope and breadth while maintaining the desired technical and scientifi c depth. I began by refl ecting on the term “wood defect” and the unfortunate way it can stigmatize wood. Can’t the same characteristic that prevents the wood from being used for a specifi c pur- pose actually make it suitable for another? Of course. For this reason, going forward I began using the more neutral term “wood characteristics”. The book begins by discussing the “General factors leading to the formation of wood char- acteristics”. These infl uences are responsible for the diversity among the wood characteristics. T he individual characteristics are then categorized into four groups of wood characteristics. 1. Wood characteristics inherent in a tree’s natural growth . These include changes to a tree’s stem contour, limbiness and anatomical structure. 2. Biotically induced wood characteristics . Involving all tree internal and external wood characteristics created by micro-organisms, animals and humans or plants. 3. Abiotic induced wood characteristics . Wood characteristics created by heat, cold, humidity, wind and other external forces. 4. Crack forms and causes , where different causes can lead to cracks with similar forms or different forms can have the same causes, are assigned to a separate group of characteristics. The chapters on the individual characteristics generally cover these fi ve questions: 1. How can the characteristic be described (anamnesis)? 2. What are its causes (diagnosis)? 3. How can characteristics be infl uenced as the tree grows (prophylaxis)? v vi Preface 4. How does a characteristic effect the various ways the wood is used (impact assessment)? 5. How can technology respond to wood characteristics (treatment)? T he discussion on the individual wood characteristics is supported by corresponding illus- trations and a separate section of photographs shows examples of how the characteristics typi- cally appear in nature. The English edition of “Wood Characteristics” maintains the same objective as the 3rd 2010 German edition (Richter 2010). The book addresses all who work with wood professionally. Foresters, gardeners and arbor- ist want to be able observe a living tree and identify its internal features and the causes of any existing wood characteristics. Based on these fi ndings they can determine how to avoid certain undesirable characteristics, or alternatively how to promote favorable characteristics as the tree and stand grow. M y aim is also to address wood technologists seeking to prevent the impact of adverse wood characteristics on wood processing, or enhance any favorable wood characteristics, as the case may be. Lastly, it gives options for technically adapting, handling and processing wood with specifi c wood characteristics. Botanists and dendrologists learn how wood characteristics occur, how they affect living trees and wood products, and how they can be either avoided or encouraged. New to this English edition is a comparison of wood characteristics found in trees from the boreal, temperate and tropical climate zones. The results show a clear relationship between the effects of sunshine duration, the vertical and horizontal angle of radiation, and crown coverage and the way wood characteristics form. The infl uence of wood characteristics on wood quality – compiled in numerous national wood grading standards – is discussed to an extent that clearly shows the connection between wood quality and wood price in the timber industry. The knowledge gathered in this book is based on the scientifi c and practical work of forest- ers, wood technologists and biologists spanning many generations. Without them, but also without the more recent generous support of certain people and institutions, this edition of the book could certainly never have been completed. Therefore I extend my special thanks to Michael Köhl, Institute for World Forestry at the University of Hamburg, for encouraging me to pursue this new edition; Gerald Koch and Hans-Georg Richter (Thünen Institute of Wood Research Hamburg) for supporting me with their wood science expertise. I would like to thank the German Federal Ministry for Food and Agriculture (BMEL) for providing the material basis for the necessary research in the tropics; the staff at the Centre for Agricultural Research (CELOS), the Stichting voor Bosbeheer en Bostoezicht (SBB) as well as Jos Dennebos, Herman Fräser and Rasdan Jerry (E-Timberindustry) in Surinam, along with my colleagues Bernhard Kenter, Timo Schönfeld and Lars Niemeier (University of Hamburg), who helped make the wood science research in Surinam possible. My great appreciation is extended to my fellow colleagues from the School of Forestry Management at the Technical University of Dresden, especially Claus-Thomas Bues and Ernst Bäucker, for the photographic material they provided and the insights I gained from them dur- ing our numerous professional discussions. I also sincerely thank Susan J. Ortloff (Oregon, USA) for her sensitive translation. The fi nancial resources for this purpose were mainly provided by the University of Hamburg and the BMEL. Representative for professional cooperation with Springer-Heidelberg, I thank Christina Eckey (Senior Editor, Plant Sciences) and Anette Lindqvist (Production Coordinator) for edi- tion from “Wood Characteristics”. Last but not least, I thank my wife, Dorothea, for her many years of patient understanding when quite often, instead of spending time with her, I spent it entrenched in this project. Tharandt, Germany Christoph Richter Summer 2014 Contents Part I Wood, a Truly Remarkable Material 1 The Anatomical Structure of Wood . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 2 Wood Characteristic or Defect?. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 3 General Factors Leading to the Formation of Wood Characteristics . . . . . . . . 11 3.1 Genetic Predispositions, Genetic Alterations . . . . . . . . . . . . . . . . . . . . . . . . . . 11 3.1.1 Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 3.2 Impact of Physiological Processes Occurring Within the Tree . . . . . . . . . . . . 13 3.2.1 Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 3.3 Light/Radiation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 3.3.1 Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 3.4 Mechanical Stress. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 3.4.1 Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 3.5 Injury . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 3.5.1 Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 3.6 Summary of the general factors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 Part II Wood Characteristics Overview 4 Overview of the Main Wood Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29 Part III Description of the Wood Characteristics 5 Wood Characteristics Inherent in a Tree’s Natural Growth . . . . . . . . . . . . . . . . 35 5.1 Stem Contour Modifi cations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35 5.1.1 Taper . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35 5.1.1.1 Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35 5.1.1.2 Causes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37 5.1.1.3 Prevention . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37 5.1.1.4 Impact on Use . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37 5.1.1.5 Technological Adaptation . . . . . . . . . . . . . . . . . . . . . . . . . . . 38 5.1.2 Crookedness . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38 5.1.2.1 Causes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44 5.1.2.2 Prevention . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44 5.1.2.3 Impact on Use . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45 5.1.2.4 Technological Adaptation . . . . . . . . . . . . . . . . . . . . . . . . . . . 45 5.1.3 Forking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46 5.1.3.1 Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46 5.1.3.2 Causes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51 5.1.3.3 Prevention . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51 vii viii Contents 5.1.3.4 Impact on Use . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51 5.1.3.5 Technological Adaptation . . . . . . . . . . . . . . . . . . . . . . . . . . . 52 5.1.4 Out-of-Roundness . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52 5.1.4.1 Ovality/Eccentric Growth . . . . . . . . . . . . . . . . . . . . . . . . . . . 52 5.1.4.1.1 Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52 5.1.4.1.2 Causes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55 5.1.4.1.3 Prevention . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56 5.1.4.1.4 Impact on Use . . . . . . . . . . . . . . . . . . . . . . . . . . . 57 5.1.4.1.5 Technological Adaptation . . . . . . . . . . . . . . . . . . 57 5.1.4.2 Seams, Flutes, and Flanges . . . . . . . . . . . . . . . . . . . . . . . . . . 58 5.1.4.2.1 Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58 5.1.4.2.2 Causes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63 5.1.4.2.3 Prevention . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64 5.1.4.2.4 Impact on Use . . . . . . . . . . . . . . . . . . . . . . . . . . . 64 5.1.4.2.5 Technological Adaptation . . . . . . . . . . . . . . . . . . 65 5.2 Limbiness . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65 5.2.1 Live and Dead Limbs, Epicormic Shoots, and Branches . . . . . . . . . . . 65 5.2.1.1 Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65 5.2.1.2 Causes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74 5.2.1.3 Prevention . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75 5.2.1.4 Impact on Use . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77 5.2.1.5 Technological Adaptation . . . . . . . . . . . . . . . . . . . . . . . . . . . 82 5.2.2 Limb Scars . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83 5.2.2.1 Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83 5.2.2.2 Causes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92 5.2.2.3 Prevention . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92 5.2.2.4 Impact on Use . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93 5.2.2.5 Technological Adaptation . . . . . . . . . . . . . . . . . . . . . . . . . . . 93 5.3 Anatomical Structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 94 5.3.1 Irregular Tree Rings/Growth Zones . . . . . . . . . . . . . . . . . . . . . . . . . . . 94 5.3.1.1 Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 94 5.3.1.2 Causes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97 5.3.1.3 Prevention . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 101 5.3.1.4 Impact on Use . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 101 5.3.1.5 Technological Adaptation . . . . . . . . . . . . . . . . . . . . . . . . . . . 101 5.3.2 Grain Orientation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 104 5.3.2.1 Spiral Growth . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 104 5.3.2.1.1 Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 104 5.3.2.1.2 Causes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 108 5.3.2.1.3 Prevention . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 109 5.3.2.1.4 Impact on Use . . . . . . . . . . . . . . . . . . . . . . . . . . . 109 5.3.2.1.5 Technological Adaptation . . . . . . . . . . . . . . . . . . 111 5.3.2.2 Grain Orientation: Curly, Fiddleback, and Hazel Growth . . . 115 5.3.2.2.1 Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 115 5.3.2.2.1.1 Assessment . . . . . . . . . . . . . . . . . . . 121 5.3.2.2.2 Causes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 121 5.3.2.2.3 Prevention . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 124 5.3.2.2.4 Impact on Use . . . . . . . . . . . . . . . . . . . . . . . . . . . 124 5.3.2.2.5 Technological Adaptation . . . . . . . . . . . . . . . . . . 124 Contents ix 6 Biotically Induced Wood Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 125 6.1 Impact of Microorganisms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 125 6.1.1 Necroses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 125 6.1.1.1 Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 125 6.1.1.2 Causes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 127 6.1.1.2.1 Measurement . . . . . . . . . . . . . . . . . . . . . . . . . . . . 127 6.1.1.3 Prevention . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 127 6.1.1.4 Impact on Use . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 127 6.1.1.5 Technological Adaptation . . . . . . . . . . . . . . . . . . . . . . . . . . . 128 6.1.2 Growth Anomalies Caused by Growth- Stimulating Microorganisms: Galls, Burls, and Witches’ Brooms . . . . . . . . . . . . . 128 6.1.2.1 Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 128 6.1.2.1.1 Measurement . . . . . . . . . . . . . . . . . . . . . . . . . . . . 133 6.1.2.2 Causes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 133 6.1.2.3 Prevention . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 137 6.1.2.4 Impact on Use . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 138 6.1.2.5 Technological Adaptation . . . . . . . . . . . . . . . . . . . . . . . . . . . 139 6.2 Impact of Animals/Humans . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 139 6.2.1 Vertebrates: Browsing, Fraying, and Stripping Damage . . . . . . . . . . . 139 6.2.1.1 Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 139 6.2.1.2 Causes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 140 6.2.1.3 Prevention . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 144 6.2.1.4 Impact on Use . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 146 6.2.1.5 Technological Adaptation . . . . . . . . . . . . . . . . . . . . . . . . . . . 147 6.2.2 Forestry Operations: Felling and Hauling Injuries (Plant Exudates) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 147 6.2.2.1 Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 147 6.2.2.2 Causes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 152 6.2.2.3 Prevention . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 154 6.2.2.4 Impact on Use . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 154 6.2.2.5 Technological Adaptation . . . . . . . . . . . . . . . . . . . . . . . . . . . 156 6.2.3 Stem Splinters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 156 6.2.3.1 Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 156 6.2.3.1.1 Measurement . . . . . . . . . . . . . . . . . . . . . . . . . . . . 156 6.2.3.2 Causes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 158 6.2.3.3 Prevention . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 162 6.2.3.4 Impact on Use . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 162 6.2.3.5 Technological Adaptation . . . . . . . . . . . . . . . . . . . . . . . . . . . 163 6.3 Impact of Plants: Epiphytes and Vines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 163 6.3.1 Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 163 6.3.2 Causes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 166 6.3.3 Prevention . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 173 6.3.4 Impact on Use . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 173 6.3.5 Technological Adaptation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 174 7 Abiotically Induced Wood Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 175 7.1 Temperature-Humidity Effect . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 175 7.1.1 Bark Scorch/Sunburn . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 175 7.1.1.1 Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 175 7.1.1.2 Causes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 178