Trash or treasure?
Logging and mill residues in Asia and the Pacific

Table of contents

Thomas Enters

The designations employed and the presentation of material in this publication do not imply the expression of any opinion whatsoever on the part of the Food and Agriculture Organization of the United Nations concerning the legal status of any country, territory, city or area or of its authorities, or concerning the delimitation of its frontiers or boundaries.

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, electronic, mechanical, photocopying or otherwise, without the permission of the copyright owner. Applications for such permission, with a statement of the purpose and extent of the reproduction, should be addressed to the Senior Forestry Officer. Food and Agriculture Organization of the United Nations, Regional Office for Asia and the Pacific, 39 Phra Atit Road, Bangkok, Thailand.

Cover photos: Sarawak Timber Association and Thomas Enters

For copies of the report, write to:

Patrick B. Durst
Senior Forestry Officer
FAO Regional Office for Asia and the Pacific
39 Phra Atit Road
Bangkok 10200
Tel: (66-2) 697 4000
Fax: (66-2) 697 4445

Food and Agriculture Organization of the United Nations Regional Office for Asia and the Pacific, Bangkok 2001 © FAO

ISBN 974-7946-12-2


For the past several years, efforts in the Asia-Pacific region have focused on achieving sustainable forest management and developing a viable forest industry sector. As a result, we have experienced considerable shifts in policies and legislation as well as institutional arrangements. On the ground, forest management is changing and forest industries continue to adopt new technologies.

While forestry has come a long way, foresters in the region cannot be complacent. One reason for taking a fresh look at how we manage our forests and use wood is the high volume of wood waste or residues produced in this region. In the past, forest industries had assumed an almost infinite supply of raw materials that the region's forests provide. Today, this erroneous perception is not as common as it used to be and raw material shortages are occurring. In response, the industry has looked for resources further afield, largely neglecting a rather different approach, i.e. to explore how wood can be harvested and used more efficiently for the benefit of today's societies and future generations.

One reason why high wood residue volumes persist is that the issue is not viewed as a serious problem. Estimates on available volumes of wood residues are few and often out-dated. They do not distinguish between total biomass and raw material that can be economically extracted and used for further processing, which hinders the development of policies encouraging the proper use of the region's forests. Also, while some have recognized wood “waste” as a valuable by-product for further processing or energy-generation, the majority still struggles with what are perceived to be “waste disposal problems,” due to a lack of knowledge about opportunities.

The seventeenth session of the Asia-Pacific Forestry Commission (APFC), convened in 1998, recognized the slow progress of many countries in reducing logging and mill residues. Therefore, the Commission requested a study on the magnitude of the problem and alternative uses for logging and mill residues. In presenting this study, FAO is pleased to continue its support of efforts to promote sustainable forest management in the region. We hope that this publication will help policy makers to better understand the key issues, challenges and opportunities related to logging and mill residues-leading to concrete measures for increasing efficiency and minimizing waste.

 R.B. Singh
Assistant Director-General and
Regional Representative for Asia and the Pacific
Food and Agriculture Organization of the United Nations


The USDA Forest Service and FAO Regional Office for Asia and the Pacific provided financial support for the study.

Appreciation is acknowledged to those individuals who provided valuable technical documents and guidance throughout the study. The country case studies for China and Indonesia were prepared by Chen Xuhe (Chinese Academy of Forestry, Beijing), and A. Ng. Gintings and Han Roliadi (Forest Product and Socio-economic Research and Development Centre, Bogor), respectively.

Patrick Durst, FAO Senior Forestry Officer (Asia and the Pacific) provided overall supervision and technical guidance for the project and editing support for the publication. Tan Lay Cheng assisted in proofreading the final document. Their professional contributions are gratefully acknowledged.

Hyperlinks to non-FAO Internet sites do not imply any official endorsement of or responsibility for the opinions, ideas, data or products presented at these locations, or guarantee the validity of the information provided. The sole purpose of links to non-FAO sites is to indicate further information available on related topics.

Table of contents



List of tables

List of acronyms





Availability and use of logging residues

Current logging practices in Asia and the Pacific

Recovery rates

Logging and wood production

Availability of logging residues

Potential for reducing residue volumes

Potential for extracting and utilizing residues

Composition of logging residues

Timing of extracting forest residues

Who should extract residues?

Specialized equipment

Costs and benefits of extracting and utilizing logging residues

Current habitual constraints and lack of clear guidelines

Availability and use of mill residues

Recovery rates of sawmills and plywood mills

Composition, types and attributes of mill residues

Potential availability of sawmill and plywood mill residues

Potential utilization of mill residues

Charcoal briquettes


Wood chips, particle boards and MDF




Appendix 1: Assessment of wood residues in China

Appendix 2: Assessment of wood residues in Indonesia

List of tables

Composition of logging residues in comparison to log volume used in Malaysia (in percent)

Composition of logging residues in Indonesia

Volume of recoverable and usable logging residues in Terengganu, Malaysia

Volume of actually recovered logging residues in Terengganu, Malaysia

Volume of recovered residues in Terengganu, Malaysia

Roundwood production and consumption in selected Asia-Pacific countries in 1998 (1 000 cum)

Availability of logging residues in selected Asia-Pacific countries in 1998 (1 000 cum)

Wood processing in Asia from 1994 to 1998 (1 000 cum, pulp in 1 000 MT)

Recovery rates in the sawnwood and plywood sub-sectors

Types of residues generated during sawmilling (ten country average)

Types of residues generated during the production of plywood (ten country average)

Sawnwood production and residues in 1998 (1 000 cum)

Plywood production and residues in 1998 (1 000 cum)

Examples of co-generation plants constructed in Asian countries in the late 1990s

Production of major boards during the 1990s (million cum)

List of acronyms

AFPAAlberta Forest Products Association
APFCAsia-Pacific Forestry Commission
ASEANAssociation of Southeast Asian Nations
CPOcrude palm oil
ECEuropean Commission
GDPgross domestic product
ITTOInternational Tropical Timber Organization
MDFmedium-density fiberboard
R&Dresearch and development
RILreduced impact logging
STIDCSarawak Timber Industry Development Corporation
TOFtrees outside forests

 What if industry could turn every gram of raw resource into product? What if one company's wastes could be used as raw resources for another? A pipe dream you say. This ideal may be much closer than most people realize.
 Norman Brownlee (1998)


One of the greatest challenges of the forestry sector and the wood industries of Asia and the Pacific is the need to address and overcome declining raw material supplies, to fully utilize available resources, and to take advantage of innovations in wood processing. Lingering impediments to the sustainability of forests and forest industries are inefficient utilization of wood raw material and the high volume of residues that are left in the forest and which remain after wood processing. A growing number of timber producers in the Asia-Pacific region are facing raw material shortages and some wood processors are now operating below 50 percent of capacity. This problem is expected to worsen considerably in the next several years.

In this climate of diminishing raw material supplies, logging and mill residues are emerging as a major potential raw material source. At the same time it is hoped that more efficient use of residues can lead to a reduction in the areas logged every year (Dykstra, 2001). Moreover, dumping of waste and residues is now prohibited or very costly, and since the catastrophic fires in 1997/98, restrictions on open burning are enforced more rigorously in some countries. Encouraging opportunities may exist for dealing with these issues, however. The Asia-Pacific Forestry Sector Outlook Study gauged the potential for increasing the utilization of logging and wood-processing residues “high” and “moderate” respectively, in Southeast Asia and the Pacific (FAO, 1998).

In 1998, the Asia-Pacific Forestry Commission (APFC) urged FAO to coordinate “a review of residues availability and their current use, and report the potential availability and implications at the next session.” It further urged the consideration of strategies and policy options to encourage more efficient use of available wood residues. Other international organization are supporting complementary work in this area. Since 1998, the International Tropical Timber Organization (ITTO) has worked to develop guidelines for increasing tropical timber utilization efficiency and the reduction of losses and waste through the production chain (Zerbe et al., 2000). In 1999, the Association of Southeast Asian Nations (ASEAN) identified “Reduction and Utilization of Wood Residues” as a key focus for collaborative forestry research and development (R&D).

In industrial countries, a large share of logging and wood-processing residues is used by the pulp and wood-based panel industries. Alternatively, residues are chipped and burned by wood processors and power plants to produce steam and electricity. Strict environmental regulations concerning waste disposal, the need to reduce fire risks in forests and the high recreational values of many forests in the North (for which logging residues are a detraction) explain this development partially. Perhaps the greatest driving force, however, is the desire to rationalize and increase efficiency.

From burning slash to producing steam and electricity

The elder Armstrong quickly swivels the machine back and forth, delimbing trees and stacking them for loading. He tosses tree tops and fallen branches onto a pile that grows 7.5 metres high.

This “slash” isn't burned as it once was. Instead, the leftovers are fed into a chipping machine capable of chewing up trunks more than half-a-metre across. The chips are burned by sawmills and power plants to produce steam or electricity.

Source: Thompson, 2000

Primary mill residues constitute a particularly attractive resource. They are clean, concentrated at specific locations, and relatively homogeneous. In the United States, 98 percent of such residues are currently used as fuel or to produce other fiber products (Walsh et al., 1999). In the U.S. State of Virginia, mill residues alone account for more than 80 percent of the US$ 82.8 million that wood product manufacturers received for all types of residues in 1996 (Alderman and Smith, 1998).

Utilization of other types of residues, however, continues to be constrained by out-dated perceptions of residues as a waste problem rather than as a valuable “new” product. This helps to explain utilization rates of only around 60 percent in places such as Alberta (Canada) (Brownlee, 1998). Developments are very dynamic, however, as reflected in the establishment of an electronic marketing system for wood residues by the Alberta Forest Products Association (AFPA) in July 1999.1

Until recently, the utilization of logging and wood-processing residues in tropical countries has generally lagged behind developed countries. However, over the last five years, the number of wood-based panel producers that utilize mill residues exclusively has increased dramatically. In some countries “shortages” of residues have actually developed as a result of increased local demand for panel production. At the same time, co-generation based on wood and agricultural residues has been adopted by a growing number of factories (Pennington et al., 2000).

It is not uncommon to find more than 50 percent of the wood of the main stems of tropical trees felled for harvest to remain unutilized (Schmincke, 1995), although much higher figures have also been recorded. Timber harvesting recovery rates appear to be particularly low in Asia and the Pacific, where they average only 46 percent, compared to Africa (54 percent), Latin America and Caribbean (56 percent) and the United States (78 percent) (Dykstra, 1992, cited in Pulkki, 1997).2 Mill process yields are as low as 33 percent of delivered log volume. However, estimates on available volumes of wood residues are few and often out-dated, or do not distinguish between total biomass and raw material that can be economically extracted and used for further processing. In addition, there is no clear consensus on what constitutes “residues.” This report strives to fill the gap of understanding related to wood residues in Asia and the Pacific. It is primarily focused on the logging and mill residues of the region's tropical and subtropical countries. The report estimates the amount of wood residues available for further economical uses and discusses opportunities and potential for economic residue reduction and utilization.

1 The wood residue inventory is operational on the AFPA web site

2 A more recent study indicates that in the United States, between 1952 and 1991, logging residues as a percentage of timber removals from growing stock fell from 10 percent to 7.5 percent for softwoods and from 22 percent to 12 percent for hardwood (Haynes et al., 1995, cited by Wernick et al., 2000).


The overall objectives of the APFC study on logging and mill residues were to:


This overview report is based on country studies and a literature review. Country case studies were commissioned for China, Indonesia, Malaysia and Papua New Guinea, respectively. The country reports for China and Indonesia are included as appendices of this report (unfortunately the studies for Malaysia and Papua New Guinea were not completed). This report also draws heavily on the results of a two-year study on “Extraction and Processing of Forest Residues and Small Dimension Logs” in Malaysia (Tai and Jaeger, 1999). Additional literature was consulted to fill gaps.


“Wood residues” refer to wood left over from any conversion process, whether true refuse, wastewood or material destined for further conversion. Residues can refer to logging waste or mill waste.

“Logging residues” refer to any wood lying on the ground as a direct result of logging operations and trees severely damaged during logging operations. Approximately one-third of all logging residues originates from felled trees and the balance from residual trees destroyed or damaged during logging and extraction (Andersen, 1999a). The residues may range from portions of the trees - including high stumps - to entire trees broken during the logging process and left on the ground. They can be roughly divided into the following categories:

Logging residues can be found directly in the stump area, along skid trails and roadside landings.

In many publications, residues are only described as those trees that were felled or the parts of felled trees. This explains, in part, the tremendous differences reported among research results. Strictly speaking, damaged trees should also be counted as waste, as they will not contribute to the future crop and could have been harvested during regular felling operations.

The composition of the residues in a particular location not only affects technical options for their use but also determines costs and benefits of their extraction. Furthermore, as the Indonesian case study indicates, residues in the plantation estate sector also need to be considered, especially in the rubber and oil palm sectors.

“Wood-processing residues” or “mill residues” consist of any wood fiber not used during the conversion process at a mill - be it a sawmill, veneer mill, plywood mill, or pulp mill. It includes losses due to improper and lengthy storage. The following categories make up mill residues:3

Similar to logging residues, the composition of mill residues determines options for their use. In numerous cases, the residues - including scraps and sawdust - of one mill are the raw material for another, depending on downstream and market integration. In such cases, residues are viewed as by-products rather than waste.

3 For more detailed definitions and descriptions, see Wan Tarmeze Wan Ariffin et al. (1999)