TREE HARVESTING TECHNIQUES

TREE HARVESTING TECHNIQUES

FORESTRY SCIENCES Baas P, ed: New Perspectives in Wood Anatomy. 1982. ISBN 90-247-2526-7 Prins CFL, ed: Production, Marketing and Use of Finger-Jointed Sawnwood. 1982. ISBN 90-247-2569-0 Oldeman RAA, et al., eds: Tropical Hardwood Utilization: Practice and Prospects. 1982. ISBN 90-247-2581-X Den Ouden P and Boom BK, eds: Manual of Cultivated Conifers: Hardy in Cold and Warm-Temperate Zone. 1982. ISBN 90-247-2148-2 paperback; ISBN 90-247-2644-1 hardbound. Bonga JM and Durzan DJ, eds: Tissue Culture in Forestry. 1982. ISBN 90-247-2660-3 Satoo T and Magwick HAl: Forest Biomass. 1982. ISBN 90-247-2710-3 Van Nao T, ed: Forest Fire Prevention and Control. 1982. ISBN 90-247-3050-3 Douglas J, ed: A Re-appraisal of Forestry Development in Developing Countries. 1983. ISBN 90-247-2830-4 Gordon JC and Wheeler CT, eds: Biological Nitrogen Fixation in Forest Ecosystems: Foundations and Applications. 1983. ISBN 90-247-2849-5 Hummel FC, ed: Forest Policy: A Contribution to Resource Development. 1984. ISBN 90-247-2883-5 Duryea ML and Landis TD, eds: Forest Nursery Manual: Production of Bareroot Seedlings. 1984. ISBN 90-247-2913-0 Manion PD, ed: Scleroderris Canker of Conifers. 1984. ISBN 90-247-2912-2

Tree harvesting techniques by K.A.G. STAAF College of Forestry Swedish University of Agriculture Uppsala, Sweden and N.A. WIKSTEN Canadian Executive Overseas Montreal, PQ, Canada SPRINGER-SCIENCE+BUSINESS MEDIA, B.V. 1984

Library of Congress Cataloging in Publication Data Staaf, K. A. G. (K. Anders G.) Tree harvesting techniques. (Forestry sciences) A condensed edition of the original Swedish version of 1972. Bibliography: p. 1. Logging. I. Wiksten, N. A. (N. lke) II. Title. III. Series. SD538.S82155 1984 634.9'82 84-14692 ISBN 978-90-481-8282-4 ISBN 978-94-017-3592-6 (ebook) DOI 10.1007/978-94-017-3592-6 Copyright 1984 by Springer Science+ Business Media Dordrecht Originally published by Martinus Nijhoff Publishers, Dordrecht in 1984 Softcover reprint of the hardcover 1st edition 1984 All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, mechanical, photocopying, recording, or otherwise, without the prior written permission of the publishers, Springer-Science+Business Media, B.V.

Contents Preface Introduction TREE HARVESTING - GENERAL Tenninology Fonns of production Rationalization of the various forms of operation General objective Tree harvesting a secondary form of production Thinning and final harvest 22 13 17 19 19 20 21 22 22 PLANNING OF TREE HARVESTING Objectives and means of planning, 23 Planning requirements 23, Data required 23, Collection of stand data 24, Requirements of labour and machines 24, Preparation of the tree harvesting plan 24, Planning for low costs of tree harvesting 25, Maps 25, Planning in general - Land and Labour 28 Various forms of cooperation 28, Population and labour 29, Areas and centres of labour 31, Forest guard (ranger) district A 31, Forest guard (ranger) district B 33, Forest guard (ranger) district C 34, Growing stock and volume of timber harvested 35, Problems are solved in general and in detail 36, Trends 36, Planning in detail 38 Planning for various seasons 40, Division of the areas of treatment into parcels for felling and transport 40, Road systems and other routes of transport 41, Planning of roads 42. ENVIRONMENTAL FEATURES INFLUENCING TREE HARVESTING 43 General features of environment 43, Geographic location and extent of the work area 43. Climate features 44 Air temperature 44, Precipitation 44, Winds influence the felling of trees 45, Wind felling 45. 23

6 Terrain features 46 Classification of terrain 46, Dominant terrain features 47, Carrying capacity of ground 47, Surface structure 47, Minor obstacles 48, Major obstacles 48, Statistics on micro-terrain features 48, Slopes 49, Ground conditions 50, Surface structure 50. The trees 50 Diameter 51, Crowns 51, Limbs 52, Weight of trees 52, Density of wood, center of gravity in trunks and statistics on bark 53, Units of timber handling 55, The forest stands 56 Relationship between cost of harvesting and volume of timber 57, Thinning 58, Clearcutting 58, TREE HARVESTING TECHNIQUES 59 Partial operations 59 FELLING 60 Choice of felling object 61, Felling year-round 61, Direction of felling 61, Directed felling 61, Tools and means of felling 62 Working and holding positions 62, Preparations 63, Guiding cut and felling cut 63, Some safety rules at felling 64, Use of felling pad 66, Calculation of shearing forces 68, Cracking caused at felling by means of clipping and shearing tools 69, Felling saws 70, Circular saws for felling 70, Feller-buncher with circular saw 71, Felling head with two circular saws 73, Alternative solutions 76 Felling patterns 76 Felling along strip roads 76, Parallel felling and felling in swaths for the tree length trunk method 77, Parallel felling for the tree method 79, Delimbing and topping before felling 79, Extraction of trees in vertical position 80, Felling of whole trees 81, Lifting of whole trees 82, Trees felled with cut root systems 82, Felling or collection of several trees simultaneously 82 Manual felling 84 Manual felling with mechanized processing 84, Alternative tree part method in thinning operations using grapple saw on crane with long boom 85 Mechanized felling 87 Feller- a small skidder with straight boom 87, Feller mounted on a tracked vehicle with short boom 88, Feller 89, Feller-buncher 90, Feller-skidder (buncher) 91, Feller-delimber-buncher 91, Feller-delimber-bucker 92, Some performance data 93, Un-manned machine without operator seat in the cabin 94, Small machine for felling and bunching in thinning operations 96, Trends 98

7 DELIMBING Manual delimbing 98, Mechanized delimbing 99, The tree limb as an object of work 100, Whorls and internodes 100, Frequency of limbs 100, Diameter of limbs 100, Height to crown base 101, Resistance to shearing force at delimbing by means of cutting tools 101, Weight of limbs 103 98 Tools and means of delimbing 104 Various tools and machines for delimbing 105, A presentation of some machine types 105, Trunk embracing knives and stepwise feed 105, Removal of slash 105, Tree harvester 106, Processor 107, Pulpwood harvester 107, Trunk embracing knives and roller feed 108, The Garp Rake 08, Trunk embracing knife track and stepwise feed 109, Trunk embracing knife track and roller feed 109, Fixed cutters (or corresponding) and roller feed 110, Tools with screws 111, Most common delimbing tools 111 Conduct of delimbing 113 Some views on mechanized delimbing 114, Relationships between feeding rate, feeding capacity and infeed power 115 Manual and motor-manual methods of delimbing 104 Motor-manual methods 121, The leverage technique 122, Some safety rules at delimbing 124, Delimbing of standing trees 125 Mechanized delimbing 126 Delimbing of felled trees in horizontal position at the stump 126 Delimbing of trees in vertical position after separation at the stump 127, Method of work 128, Process of delimbing 128, Output of machine 131 Delimbing integrated with other harvesting operations 131 Mechanized delimbing, bucking and bunching at strip roads 131, Work procedure of the machine 131, Delimbing tools 131, Mechanized delimbing and bucking at landings 132, Delimbing depot 132, Felling and transport to the delimbing depot 132, Output 133, Principle of delimbing 133, Bunch delimber 133, Work procedure of the bunch delimber 134, Output 135 Trends in delimbing 135 Some views on the weight of delimbing machines 135, Increased mechanization of delimbing can be expected 135 BUCKING 142 Importance of bucking 142 Tools and means of bucking 142 Manual tools 142, Motor-manual tools 143, Mechanized bucking 143, Advantage of machine power 144 Various methods of bucking 145 Stationary bucking equipment 145, Mobile bucking equipment 145, Moving bucking equipment 146, Interrupted or continuous sequence

8 of bucking 147, Bucking of single or several trees 147 Manual and motor-manual bucking 148 Bucking at the stump 148, Bucking at various tension conditions 149, Bucking at strip roads 150, Bucking at landings 151 Mechanized bucking 151 Mechanized bucking at the stump 151, Mechanized bucking at strip roads 152, Method of bucking by means of the grapple saw 152, Method of bucking by means of a very rapid chain saw 153, Processor A 154, Method of felling 154, Various partial operations 155, Terrain travel 155, Processor B 155, Work procedure 156, Design of the machine 157, Processing of timber 157, Mechanized bucking at truck roads or industrial landings 158, Bucking of partial trunks 158, Bucking of trunks in the tree length method 159, Bucking of trunks in the tree method 159, Processor C 159, Output and costs 160, Mechanized processing of tree length trunks at industry or terminal 160, Main components of the establishment 161, Bucking-scaling 161, Mechanized processing at mobile and semi-stationary establishments 162, Partial operations in the analysis 164, Infeed 164, Delimbing 164, Scaling and bucking 164, Sorting 165, Handling of timber in a processing establishment 165 Trends in bucking 166 Increased mechanized bucking 166, Automatic scaling and bucking 167, Application of electronics 167, photo-cells 167 DEBARKING 168 Purposes of debarking 168, Debarking in the forest 168, Debarking at the industry 168, Choice of location for debarking 169, Some physiological features of bark 169, Various layers of bark 169, Cambium 169, Inner bark 169, Outer bark 170, Cohesion between bark and wood 170 Tools and means of debarking 172 Manual debarking in the forest 172, Motor-manual debarking 173, Mechanized debarking 173, Debarkers with knives 173, Debarkers with cutters 173, Debarkers with rings or rotors 173, Working principles of a debarking machine 175, Pressure of the debarking tools 176, Procedure of debarking 176, Hydraulic debarking in the forest 178, Chemical debarking in the forest 178 Debarking integrated with other harvesting operations 179 Factors influencing the result of debarking 179, Reasons for integrated debarking 179, Types of debarkers 181, Stationary debarkers 181, Semi-mobile debarkers 181, Mobile debarkers 181, Most common forms of organization at debarking by means of small units 182, Debarker mounted on tractor 182, Debarker mounted on tractortrailer 182, Mobile debarker 182, Debarking of pulp-wood in troughs 183, Development trends in debarking 163, Relationship between the cost of manual work and degree of mechanization 184, Cost of labour climbs faster than machine costs 185, Investments required 185, Trends in concentration 186

9 BUNCHING Manual bunching 187, Bunching by means of horses or tractors 187, Purpose of bunching 187, Work techniques and equipment 189, Manual bunching 189, Bunching by means of winch 189, Bunching by means of crane 189, Bunching by means of processing machines 189 187 Various fonms of bunching 190 Manual forms of bunching 190, Bunching of bucked timber 190, Bunching of tree length trunks 190, Bunching in combination with delimbing 190, Bunching in combination with bucking 191, Bunching of trees 191, Bunching in combination with transport 191, Bunching in combination with processing of trees 191, Bunching in combination with processing of bunches 191, Bunching integrated with other harvesting operations 191, Trends in bunching 191, Description of a machine for bunching-delimbing of trunk sections- 1983 model, 192 CHIPPING 194 Needles, bark and cones 194, What is chips? 194, Chipping - fuelwood 195, Types of chipping machines 195, Chipping with portable chippers 196, Chipping in the forest 197, Chipping of residues from thinning operations (tops and limbs for fuel) 200 Tractor mounted chipper 200, Chipping of energy forests and tree harvesting residues requires efficient equipment 201 Coordination of the various partial operations 202 Coordination 202, Rational coordination 203, Objective of production 203, Various modes of production 204, Systems of various modes of production 205, Continuous systems with parallel coupling 205, Costs of capital and operation 206, Utilization of equipment 207, Production 207, Integration of partial operations in harvesting machines 208. TRANSPORTS OF TIMBER IN TERRAIN 211 Costs of transports 211, Some transport concepts 212, Transport in terrain and transport on roads 212, Short transports and long transports 213, Driving and terminal work 213, Forest roads and timber terminals 213, Most common types of forest roads 213, Terminal locations 214 Forwarding 214 Choice of transport method in terrain 215, The horse 215, Expanding truck road systems in the forests 215, Tractors for tree harvesting 216, Current transport infrastructure 216 Objects of transport 216 Volume, weight and shape of timber 216, Quantity of transports 216, Volume of timber 217, Costs of tree harvesting 217, Size of the clearcut areas 218, Dimensions of the transport objects 218, Piling of the transport objects 218, Weight of timber 219

10 Routes of transport 219 Various routes of forwarding 219, Patterns of strip road systems and road net density 220, Various patterns of road systems 220, Optimum density of the road systems 222, Length of strip roads 222, Relationship between strip roads and the truck road 224, Terminals 224, Various types of terminals 225, Terminals on ice 225, Preparation of ice 226, Various methods of ice preparation 226, Quality of ice 227, How is watering done? 227 Means of transport 227 Means of transport on land, water and in air 227, Transports on land 228, Transports on water 228, Transports below the water surface 228, Transports by aircraft 228 Live means of transport 229 Conditions for transport by horse in general 230, The performance of a horse in haulage 230, Traction 230, Minimum possible loss of power 230, Final harvest operations 232, Thinning operations 233, Other tree harvesting operations 234, Harvest of fuelwood from cleaning operations 235, Manual winches 238, motor powered winches 239 Tractor as a means of transport in harvesting operations 239 Development of the tractor 239, The forest tractor 240, Requirements of the tractor 240, Ability to travel in terrain 241, The tractor wheel 241, Improved knowledge of wheels and wheel combinations is needed 241, Difference in resistance to rolling between twin wheels and single wheels 242, Standardization of tractor wheels 243, The wheel is the cause of biological concern 243, Damages to the ground 243, How can rutting be counteracted? 244, Improvement of traction 245, Minimizing losses of motor power 245, Forces acting around a wheel 245, What is to be gained by larger wheel diameter and wider tires 246, obstacles 246, Slopes in terrain 247, Carrying capacity 247, High hauling capability required 247, Practical hauling capability 248 Cranes and winches 248 Cranes 249, Knuckle boom cranes 249, Characteristics of the crane 249, Steering levers 251, Winches 252 Methods of transport in terrain 253 Skidders and forwarders 253, Methods of transport by means of tractors 253, Transport of trees by means of tractor 255, Transport of whole trees to strip roads within 100 m distance 255, Transport of whole trees within a distance of 400 m 255, Skidders equipped with winch 256, Skidders equipped with clam bunk 256, Skidders equipped with grapple 258, Transport of tree length trunks 258, Skidding by means of winch 259, Skidding by means of clam bunk 259, Transport of assortments or timber bucked into multiple length 260, Wheel forwarders 260, Track forwarders 260, A 16-wheel forwarder for difficult terrain 261, High load capacity 262

11 Transport performance 262 Calculation of the transport performance 262, Transport factors 262, Technical factors of transport 263, Travel time 263, Road distances 263, Speed of travel 264, Traction 264, Terminal time 264, Terminal time for loading 264, Loading of assortments (short wood) or bucked timber 266, Loading of trees and tree length trunks 266, Terminal time for unloading 267, Layout of landing 267, Method of unloading 267, Relationship between travel time and terminal time 268, Size of load 269, Traction 269, Ground pressure 269, Practical hauling capability 270, Optimum load capacity 270, Slope resistance 271, Resistance to skidding 271, Resistance to rolling 271, Total and maximum resistance to movements 271, Organizational factors of transport 272, Planning and organization 272i Well trained personnel 272, Good machines and tools 272, Some desirable ergonomic and technical data on a modern forwarder, 272, Technical data for two different forwarders 273, Economic matters 273, Performance data 230, Costs of capital and operation 273, Relationship between terminal costs and travel costs 273 Trends of transports in terrain 274 Development of a forest tractor 274, The first forest tractor 275, Hydrostatic-mechanic power transmission 277, Comparison of performance 279 Further transport in forest operations 279 Forms of further transport 279, Conditions of further transport 280, Objects of further transport 280, Routes of further transport 281, Forest roads 281, Slopes 281, Curves 281, Width of road surface 281, Maintenance of the roads 282, Travel speed 282, Location of terminals 282, Means of transport 283, Trucks (lorries) 283, Requirements concerning the truck 283, Transport by trucks 284, Loading 286, Unloading 286, Measurements and weighing of timber 286, Combination truck and railway 288, Railways 288, Rivers 289, Means of transport 290, River drive as a method of transport 290, Methods of transport 291, Choice of method for further transport 291, Distribution of transports 292, Trends in further transports 292 TREE HARVESTING TECHNIQUES APPLIED IN FIVE BASIC METHODS 293 Various methods of harvesting 293, Thinning operations 293, Final harvest operations 293, The assortment (short wood) method 295, Semi-mechanized assortment method 296, Entirely mechanized assortment method 296, The tree length (trunk) method 297, Entirely mechanized tree length method 297, The tree method 298, The tree part method 301, Examples of tree part methods 301, A. Thinning operations 301, B. Final harvest operations 303, The chip method 253, Chipping of trees from cleaning at truck road 304, Transport of chips to the consumer 304, Transport of residues for chipping at industry 306, Chipping of stumps 307, Chipping integrated with the tree method and the tree part method 307, The tree method and the tree part method applied at thinning operations 308, A. Equipment for the tree method 308, B. Equipment for the tree part method 309, Various degrees of mechanization 313, Partial operations 316

12 Choice of harvesting method 317 Factors influencing the choice of harvesting method 317, Methods of harvesting in thinning 317, Thinning operations 318, Planned motor-manual felling in thinning operations 319, Principles of felling in conventional thinning operations 320, Principles of felling in thinning operations with winch 320, Methods of harvesting in mature stands 323, Final harvest operations 323, The assortment (shortwood) method 324, Assortment method 325, Planned final harvest operation with motor-manual felling 325, The tree length (trunk) method 326, The tree method 327, Degree of mechanization 327, Mechanized systems with processing in the forests 328, Mechanized systems with processing at terminal or at industry 328, Mechanized systems with limited crews 328, Degree of mechanization 330, Machine development 331, Potential man-machine systems for thinning 333, Thinning by means of a machine for harvesting in swaths 333, Thinning by means of a tower crane 334, Thinning by means of multi-tree fellers 335, Integration of harvesting and transport 336, Performance analysis of a machine designed for thinning 337 Analysis of a man-machine system for thinning 337 HMG 8 logging machine, Description of machine 337, Description of the method 338, Example of performance 340, Results 343, Comments 343 WORK STUDIES 345 Work studies as a source of reference 345, Ergonomics 345, Work studies 345, Work 346, Objectives and means of work studies 346, Various forms of work studies 346, Object of the study 346, Purposes of study 347, Methods of study 347, Measurements 347, Time studies 347, Frequency studies 348, Studies of statistics 348, Application of work studies 348, Elements of time 349, Purpose of work studies 350, Studies of rationalization 350, Forms of work studies in forest operations and in industries 351, Key work of an agreement in forest operations 352, Elementary time systems 353 Work physiology 354 Physiological capabilities and limitations of Man 354, Check lists 354, Individual limitations 354, Medical limits 355, Physiological limits and performance 355, Physiological and psychological measurements of work 355, Physiological measurements 355, Variation in work capability 356, Physiological work load 357, Most common methods of measuring work load 358, Need for physiological measurements of work 358, Combinations of work, breaks and rest 359, Nutritional requirements 360, Briefly on pulse rate at rest and at work 361 REFERENCES 363

Preface The introduction of chain saws and tractors in the early 1950's marked the beginning of a change in tree harvesting techniques from the old manual methods to mechanized operations. It was followed by a rapid evolution both technically and systematically. Hence, the requirements for improved knowledge of operational efficiency also increased. Changing relations between Man, machines and environment brought about new experiences and awareness of a physiological and ergonomic nature. Improved knowledge of both machine technology and planning of work on a small or large scale has grown increasingly important for an efficient utilization of expensive machines and other equipment. The need for a textbook on tree harvesting techniques including experiences made in recent years is enhanced. The book presented here is primarily based on lectures given on the subject of Forest Techniques at the Faculty of Forestry at the Swedish University of Agricultural Sciences and after modifications also at the University of Nairobi (Kenya). Thus, the book is written primarily for students at the faculties and institutes of forestry. However, it is also useful for persons actively occupied in forest operations. The presentation of this book in its original Swedish version in 1972 created a considerable interest in the preparation of a condensed edition in English. Thus interest has been expressed in Finland, Norway, Holland, Canada, U.S.A., Brazil, Japan, Poland, Scotland and Yugoslavia. The authors have interpreted the widespread interest in the previous edition as an interest in the techniques of tree harvesting as applied primarily in the Nordic countries. Most references to various sources of basic information in the Swedish edition of 1972 were of Swedish, Norwegian, Danish and Finnish origin and written in the native languages only. A large part of it was based on lectures given at the Faculty of Fares try at the Swedish University of Agri-

14 culture. Although most of this background information is available in the native languages only, it has been considered desirable to quote and date the references in the English edition in case they are of interest for translation. Working in close contact with specialists in several countries the authors have solicited their viewpoints on this attempt at preparing an international textbook on "Tree Harvesting Techniques". Naturally, it has been difficult to accommodate all wishes and recommendations without contradictions but we have tried to arrive at a certain balance of opinions on the basis of reason and logic. Still, in view of the common background of the authors, it can be reasonably expected that some of the statements have been subconsciously tainted by the conditions prevailing in the Nardi c countries. Although the title of the book has been made more specific than that of the first edition (in Swedish only), the authors have decided, space permitting, to retain an abbreviated review of the planning process in order to give a logical background to the choice of harvesting systems. Tree harvesting techniques is not only a matter of machines but also of the appropriate ways of operating the machines under various environmental and socioeconomic conditions. The application of tree harvesting techniques depends on recommendations given in the plans for regulated harvest of forest products. A mere description of machines and their use would make the book just a catalogue of equipment. To write a book for specialists would be presumptuous, the specialists having a tendency to contradict each other depending on the special conditions of their own countries. There is no final word in science and there is no single machine, method or system that is correct for all situations and conditions. What may be right for the exploitation of old, big timber today over large areas will not be the right techniques for the harvest of timber of various assortments from new, more uniform stands of man-made forests. The final sections of this edition in English have been devoted to a brief description of ergonomics and its importance for the rationalization of the tree harvesting operations. For their comments and recommendations we are particularly grateful to the following persons: Professor Dr. Marten Bol, The Netherlands, Professor Dr. Branko Mihac, Yugoslavia, Professor Dr. Kalle Putkisto, Finland, Professor Dr. Ivar Samset, Norway and Dr. Hon. Ross Silversides, Canada.

15 A quick linguistic evaluation has been provided through the cooperation of the Editor of the Petawawa National Forestry Institute, Mr. Yapo, Canada. To all these persons we want to express our sincere gratitude. Technical illustrations have been reprocessed at the Faculty of Forestry mainly through the valuable and knowledgeable efforts by photographer Jonas Palm and artist/forest technician Sigurd Falk. Institute secretary Sigbritt Israelson has worked very energetically and persistently with typing, corrections and lay-out of the manuscript. The authors wish to express their most heartfelt gratitude to these three devoted co-workers at the Faculty. Last, but not 1 east, we wish to thank the Faculty of Forestry at the Swedish University of Agricultural Sciences for its support and assistance in various material ways. Garpenberg, Hedemora March, 1984 0 ;::lk<.....,-{tc.d;::-... Anders Staaf J\.ke Wiksten