More than ten years ago, Poore et al. (1989) noted that most of the world's tropical forests were unmanaged or managed in unsustainable ways. Since then, considerable progress has been made towards better forest management in the Asia-Pacific region, although most countries are still far from achieving sustainable forest management.
A major obstacle to applying best practices is the destructive form of logging carried out by many operators. “Forest mining” is still common in many countries (Putz et al., 2000a) and conventional crawler tractor/truck harvesting systems developed in the 1960s are still in regular use. Although more efficient and less damaging equipment exists today, it is often more expensive (or perceived to be more expensive) and/or more complicated than older equipment and therefore rarely used (Thurland, 1999).
Logging intensities in the tropical rainforests of Asia and the Pacific are substantially higher than in other regions (Putz et al., 2000b). Pinard and Putz (1996) recorded an average of 154 m3/ha in the Malaysian State of Sabah. Thurland (1999) estimated intensities between 80 and 125 m3/ha in Terengganu, Malaysia. In comparison, in the dense rainforests of West and Central Africa, logging intensity is only about 10 m3/ha (Van Leersum, 1996, cited in Wanders, 1999).
Re-logging (i.e. the premature re-entry into stands that were previously logged) within five to ten years after the first harvest is also common in Asia and the Pacific (Gillis, 1988, cited in Ascher, 1993; Smith and Applegate, 2001). Both frequency and intensity of logging operations are important determinants of logging damage and thus residue volumes.
A recent study in the Malaysian State of Terengganu concluded that largely unsupervised logging practices resulted in average logging damage percentages to residual stands of between 50 and 75 percent (Thurland, 1999). Similarly, Pulkki (1997, p. 4) concluded that “damage to the residual stand in conventional logging operations is excessive and the percent of residual trees damaged ranges from 33–70 percent in areas with higher (>30 m3/ha) logging intensity.”
Sweeping generalizations regarding logging damage are inappropriate, as substantial forest management differences can be observed among countries of the region. Technological sophistication ranges from manual logging (with or without draft animals) to helicopter logging. However, standard estimates of logging residues can appropriately be applied in countries where ground-based systems and the use of crawler tractors are still very common. This includes particularly Malaysia and Indonesia, and other countries where companies from Malaysia and Indonesia operate.
Many countries in Asia have institutionalized total or partial logging bans (Brown et al., 2001). Local wood production is therefore dramatically reduced and total residue volumes are subsequently less significant than in major wood-producing countries. Hence, refining estimates of recovery rates for countries with partial logging bans would have only a negligible effect on total volumes potentially available in the region.
However, adjustments to recovery rates were made for wood-deficit countries, where it can be assumed that higher wood prices are likely to stimulate more thorough collection and use of residues. In extreme cases, where the local population faces woodfuel shortages, virtually all residues are collected for firewood; therefore recovery rates can be considered to be close to 100 percent.
A traditional “rule-of-thumb” is that for every cubic meter of wood extracted from the forest another is left behind. This rough estimate appears to be generally validated by the Chinese and Indonesian case studies.
Log utilization rates in China range from 53.7 percent in Yunnan Province (in the south) to 70.8 percent in Jilin Province (in the northeast). Average recovery rates have been estimated at 56 percent (see Appendix 1). In Indonesia, recovery rates have been estimated at 47.6 percent for the case study prepared by Gintings and Roliadi (see Appendix 2). In other words, for each cubic meter extracted in the lowland forests of Sumatra, Kalimantan, Sulawesi or Maluku, more than one cubic meter is left behind in the forest. Up to 70 percent of wood being previously logged from natural forests in Sri Lanka was wasted because of poor harvesting methods, inefficient utilization, and the non availability of markets for some wood (Buenaflor and Karunatilleke, 1992, cited in Pulkki, 1997).4
A study in the Malaysian State of Sarawak (Noack, 1995) showed that, on average, about 54 percent of the total wood volume (diameter above 20 cm) was extracted in the form of logs. The log utilization rate in East Kalimantan is about 53 percent (McLeish and Susanty, 2000). A recovery rate of 56.4 percent is the average for “normal” concessionaires with little or no downstream woodworking capabilities in Terengganu (Andersen, 1999a). The highest utilization rate of 65.9 percent was found for a concessionaire with large downstream wood-processing facilities. This operator reduced especially the volume of wasted top logs and various off-cuts (Table 1), thus indicating that the potential for reducing waste in the forest is real and can be profitable. It also highlights that not all residues are usable or can be extracted and transported in a cost-effective manner.
Table 1. Composition of logging residues in comparison to log volume used in Malaysia (in percent)
|Study||Log used||Stump||Top logs||Branches||Various off-cuts|
|Scharai-Rad, 1995||56.8||9.7||17.1||16.4||incl. in top logs|
* includes data for Malaysia, Indonesia, Ghana and Cameroon
Source: Jaeger 1999a; only residues originating from individual trees.
The available figures indicate a fairly common recovery rate of about 55 percent, with higher rates in the temperate forests of China. Lower recovery rates can be expected during “hit-and-run” harvesting operations or large-scale illegal logging. Reliable statistics on the extent of illegal logging are scarce, but it is prevalent in most countries of the Asia-Pacific region with volumes of illegally cut trees ranging from a few hundred to millions of cubic meters per year. On the other hand, most research has been conducted in the tropical rainforests of Malaysia and Indonesia, where most of the commercial logging is taking place. In drier forest types and in wood-deficit situations, recovery rates are considerably higher, which needs to be considered in assessing the overall availability of raw material.
Moreover, very little is known about recovery rates for plantations in the Asian tropics. Much depends on the end use, distance to markets, standards of the industry, and whether one considers final harvests or thinning operations. Andersen (1999b) estimated that only about 30 percent of the felled trees in an Acacia mangium plantation was removed during thinning operations. The 60 m2/ha (above 5 cm) left behind in the plantation had no commercial value, since there were no wood-based panel producers of chip mills in the plantation's vicinity. In fact, Andersen's study revealed that the extraction of the thinning residues would result in a loss of 65 Malaysian ringgit (or about US$ 17) per m3. This highlights the importance of the location of plantations vis-à-vis processing facilities. In fact, as Ravn (1999a) has shown for Malaysia, available logging residues are now considered too expensive and wood-based panel and chip producers have begun to invest in their own plantations, since they believe that they can produce their own raw material close to the processing site cost-effectively for less money than the cost of residues.
4 Note that Sri Lanka banned logging in natural forests in 1990.
The recovery rates discussed above are based on studies of individual trees. Hence, they fail to account for what actually happens to a forest during logging operations, including failure to account for damaged or destroyed trees that were not intended for felling and extraction. Based on studies by Andersen (1999a), only one-third of the total volume of forest residues originates from the individual trees felled. The other two-thirds consist of trees damaged or destroyed during road construction, logging and extraction. Very different figures are quoted for Indonesia where damaged trees make up less than 5 percent of the total volume of residues (Table 2). The available information does not allow for a detailed analysis of the differences. It is probably safe to say, however, that during harvesting operations in tropical rainforests, for every cubic meter taken out of the forest two cubic meters are left behind, either as residues on the forest floor or as standing damaged or dead trees.
Much higher recovery rates are possible
At present, the problem with plantation residues [in Malaysia] is not solved. The recovery rate of small logs in the ongoing traditional thinning in the Merchang plantation is only about 30 % of the total thinned volume. The logs are used for pallet wood at a recovery rate of about 25 % (similar to rubberwood processing), which means that only 7–8 % of the total felled volume is currently used.
Recently, mechanized whole tree thinning has been tried by Merbok Hilir Resources Sdn. Bhd. in Merchang with promising results. The recovery rate is around 80 % of the thinned volume. The damage level is acceptable and the method effectively solves the problem of labor shortage. The whole trees are chipped [in the forest] for the manufacture of MDF …[medium density fiberboards] at Merbok Hilir Resources Sdn. Bhd. in Kedah.
Source: Ravn, 1999b
Table 2. Composition of logging residues in Indonesia
|Component||Amount (m3 per ha)||Amount (percent)|
|Upper portion of the tree trunk including branches, smaller branches and twigs||37.29||45.35|
|Damaged standing trees, due to felling and skidding,||3.96||4.82|
|Commercial wood logs of unacceptable qualities, due to knots, crooks, reaction woods and other defects||15.66||19.05|
|Unknown or non-commercial tree species||1.33||1.62|
* Based on observations/assessments in lowland production forests (Idris, 1995, cited by Gintings and Roliadi, see Appendix 2).
All logging operations generate waste. The question is not one of avoidance, but rather of minimization and utilization. The real question is then how much of the total volume can be used economically. Some analysts find it useful to distinguish between “usable” and “economically usable,” although clear definitions have not yet been developed (see China case study in Appendix 1). In China, for example, 8 to 15 percent of the logging residues are categorized as usable depending on forest types. Only 5.6 to 9 percent of residues are classified as economically usable.
Detailed measurements in Terengganu, Malaysia, indicated that about 20 percent of the total amount of forest residues is directly usable for primary processing (Table 3). These estimates must be viewed with caution, however, because the extraction of logging residues solely for chips and fiber use is presently not economically attractive relative to the use of mill residues or residues derived from estate crops such as rubber (Azizol Abdul Kadir et al., 1994; Andersen, 1999a).
Moreover, the directly usable volume may not correspond with the volume that loggers are interested in actually recovering, which can lead to a considerable reduction in the amount of residues that could be removed potentially. In the study in Terengganu, loggers extracted only 23 percent of the logs that had been tagged as “recoverable” (Table 4). While there are probably numerous explanations for this phenomenon, a major one is the apparent preference for particular, i.e. the most valuable, species (Table 5).
Table 3. Volume of recoverable and usable logging residues in Terengganu, Malaysia
|No. of pieces||Volume (m3)||Percent||Species|
|Top logs from originally tagged trees (first operation)||123*||67.96||3||All species|
|Top logs from originally tagged trees and severely damaged trees (second operation)||325**||371.39||17||All species|
|Total volume of recoverable residues||448||439.26||20||All species|
|Volume of main logs extracted||n/a||2 184.52||100||All species|
Source: amended Jaeger, 1999b
* Residues from the first operation were extracted simultaneously with the main logs
** 280 pieces or 86 percent originated from severely damaged trees
Table 4. Volume of actually recovered logging residues in Terengganu, Malaysia
|Total volume of main logs extracted||2 184.52|
|Volume of residues tagged for extraction in second operation||371.39||100|
|Volume of tagged residues extracted in second operations||88.02||23|
|Volume of residues extracted in first operation||67.96|
|Total volume of residues actually extracted||155.98|
Source: amended from Jaeger, 1999b
Table 5. Volume of recovered residues in Terengganu, Malaysia
|Volume (m3)||Percentage of total volume tagged for extraction||Species|
|Total volume of extracted residues||509||5||Chengal, Balau, Meranti and Kempas|
|Volume of main logs extracted during regular harvesting||10 662||100||All species|
Source: amended from Jaeger, 1999b
Results from studies in Brazil (Gerwing et al., 1996, p. 25) indicated that by “eliminating timber losses to trees that are felled but never found [by skidding operators] and losses caused by poor cutting and bucking practices, the amount of timber harvested from each hectare can be increased by an average of 8.3 m3.” This is more than 20 percent of the average volume (38 m3) currently recovered. However, analysts warn that “this presupposes the processing and utilization of species that are currently not marketed” (p. 25), which confirms the findings from Malaysia by Jaeger (1999b).
Experiences of concessionaires with downstream processing facilities indicate that utilization rates can easily be raised by close to 10 percent (Table 1) above traditional recovery. The potential utilization rate is probably higher, although it is doubtful whether it is twice as high. For calculating the availability of logging residues that can be economically used without any major changes, i.e. with low investments, a figure of 10 percent will be used for the following calculations. This is half the recoverable volume that is actually suitable for primary processing, but is still between 1.5 and 5 percent above the volume loggers currently show interest in recovering.
Another reason for low recovery rates
Another reason for the low recovery rate is the attitude of the logging crews. It is human to resist changes. After being told to only harvest large dimension logs, it is a great change to get used to extracting forest residues. The productivity will of course go down drastically and it is necessary for the logging contractors to develop a different salary structure when working with forest residues.
Source: Jaeger, 1999b
The availability of logging residues is determined in part by logging rates. There are no reliable data on annual logging areas and intensities for most countries of the Asia-Pacific region. A proxy indicator of logging area is roundwood production and, in particular, the production of industrial roundwood, although the indicators do not distinguish between source of material (i.e. from natural forests or plantations). The most comprehensive data on roundwood production (Table 6) are contained in the FAO Yearbook of Forest Products (FAO, 2000). Since they largely reflect official government figures, they do not always accurately portray the actual situation.
Table 6. Roundwood production and consumption in selected Asia-Pacific countries in 1998 (1,000 cum)
|Country||Roundwood (R)||Industrial roundwood (I)||Ratio I/R (percent)||Consumption (c)||Ratio R/C (percent||Cum/1 000 capita|
|Bangladesh||33 058||617||1.87||33 004||100.16||5|
|Bhutan||1 702||45||2.64||1 702||100.00||22|
|Cambodia||8 008||1 040||12.99||7 908||101.26||88|
|China||291 886||100 918||34.57||298 178||97.89||85|
|India||299 490||25 156||8.40||301 174||99.44||27|
|Indonesia||193 218||36 195||18.73||193 329||99.94||176|
|Malaysia||29 297||21 735||74.19||23 699||123.62||754|
|Myanmar||22 430||3 444||15.35||21 757||103.09||62|
|Nepal||21 474||620||2.89||21 474||100.00||27|
|Pakistan||33 044||2 270||6.87||33 177||99.60||17|
|Philippines||42 530||3 484||8.19||42 965||98.99||54|
|Sri Lanka||10 414||706||6.78||10 411||100.03||38|
|Thailand||36 302||2 872||7.91||36 580||99.24||52|
|Viet Nam||36 232||4 525||12.49||36 222||100.03||58|
|Total of selected countries||1 063 573||204 316||19.21||1 066 002||99.77||n/a|
|Asia||1 127 267||244 044||21.65||1 150 664||97.97||75|
|Papua New Guinea||8 772||3 239||44.90||5 761||152.27||352|
Note: Minor wood producers in the Pacific were not considered in this study.
Although it is not the objective of this study to assess the validity of the data presented above, it should be noted that drastically different data sets exist for some countries. For example, while FAO (2000) indicated that 1997 industrial roundwood production in Cambodia was 1.04 million m3, data from four different sources for the same year ranged from 212 000 to 4.32 million m3 (Castrén, 1999a). For Myanmar, FAO (2000) reported production of 3.44 million m3, while Castrén's (1999b) estimates were less than 2 million m3. Gintings and Roliadi (Appendix 2) estimated log production in Indonesia at about 28 million m3. Other official figures ranged from 29.15 to slightly above 40 million m3 (FLB, 2000). Barr (2000) calculated production at 55 million m3, and referred to a 1999 study by Scotland and others which estimated production at 82.3 million m3, or nearly three times higher than official figures. For China, Chen estimated log production in 1997 was around 64 million m3 (Appendix 1), while FAO (2000) reported a figure of 109 million m3 for the same year. Finally, Thailand's industrial roundwood production was approximately 2.9 million m3, as published by FAO (2000), compared with only 54 800 m3 (including confiscated timber but apparently excluding wood sourced from plantations), as published by the Royal Forest Department (RFD, 2000).
The observed discrepancies need to be kept in mind in reviewing the availability of logging residues. They indicate that the figures in the next section are rough approximations, which suggest orders of magnitude but not exact figures for economic analysis or similar appraisals.
The main wood and timber producers in the Asia-Pacific region are very diverse in terms of socio-economic variables. Forest cover and the importance of timber industries ranges from very low to extremely high. Hence the 18 Asia-Pacific countries assessed (Table 6) were further sub-divided into three groups according to industrial wood production and per capita consumption of roundwood.
The first group consists of those countries that produce only low volumes of industrial roundwood and/or are characterized by low levels of consumption per person. In fact, in all of these countries, with the exception of Bhutan, a significant percentage of roundwood is produced from trees outside forests (TOF). It can be safely assumed that recovery rates of wood from TOFs are close to 100 percent.
Sri Lanka (38)
In the calculations below, a residue factor of only 0.25 is applied for the six countries above. This means that for each cubic meter cut one-quarter of a cubic meter is left behind.
5 Figures in parentheses represent consumption levels of industrial roundwood in cubic meters per 1 000 capita (FAO, 2000)
The second group consists of countries whose production does not satisfy demand and whose industrial roundwood production is less then 10 percent of total production. Consumption levels are still below the Asian average of 75 m3/1 000 persons. Although China has higher consumption levels and produces a considerable amount of roundwood, it is included in this group for two reasons. First, like Thailand and Philippines, it has recently introduced harvesting restrictions. Second, large forest areas are located in the temperate zone, where harvesting damage can be assumed to be lower, especially for softwoods. Chen (Appendix 1) suggested a recovery rate of 56 percent in China, although this appears to exclude the volume that could be recovered from damaged trees. Fiji is also included in this group as it is not a major exporter of logs or wood products like the countries in group 3. For further calculations, a recovery factor of 1.0 (i.e. for each cubic meter cut one cubic meter is left behind) is assumed for the four countries in group 2:
The last group comprises the timber producing countries where industrial wood production is higher that 10 percent of total wood production, and countries with consumption levels above the Asian average (with the exception of Viet Nam and Myanmar). Hence, for the first six countries, a residue factor of 2.0 is applied, and for the last two a slightly reduced factor of 1.5:
Papua New Guinea (352)
Solomon Islands (321)
Viet Nam (58)
As discussed above, for the assessment of logging residue availability it is assumed that only 10 percent of the total volume of logging residues can be used economically or is of interest to loggers (Table 7). This ratio appears to be low and is based on the current situation, which to a large extent depends on raw material prices. With rising prices, it can be assumed that the economically usable volume increases, although transport costs may rise at the same time, which further discourages the extraction of logging residues.
Table 7. Availability of logging residues in selected Asia-Pacific countries in 1998 (1,000 cum)
|Country||Industrial roundwood (I)||Residue factor||Total volume of residues||Economically usable volume|
|China||100 918||1||100 918||10 092|
|India||25 156||0.25||6 289||629|
|Indonesia||36 195||2||72 390||7 239|
|Malaysia||21 735||2||43 470||4 347|
|Myanmar||3 444||1.5||5 166||517|
|Philippines||3 484||1||3 484||348|
|Thailand||2 872||1||2 872||287|
|Viet Nam||4 525||1.5||6 788||679|
|Total of selected countries||204 316||n/a||245 900||24 594|
|Papua New Guinea||3 239||2||6 478||648|
|Solomon Islands||734||2||1 468||147|
Based on the assumptions made earlier, the total amount of logging residues generated in the 15 selected Asian countries in 1998 was 245.9 million m3, which is almost identical to the total roundwood removals of 244 million m3 for Asia. In that sense, the rule of thumb that for each cubic meter cut another one is left behind applies, although it may apply evenly to all individual countries.
It cannot be assumed that currently the potentially recoverable residues are also of interest to loggers and the wood-processing industries. As various studies have shown, a maximum of 10 percent is potentially of interest to loggers and the wood-processing industries if logging and wood processing were better integrated. This adds up to 24.6 million m3 for the 15 Asian countries and 851 000 m3 for Fiji, Papua New Guinea and Solomon Islands. The reasons for this substantial difference between potentially usable and actually recovered residues are manifold and will be discussed below.
The bulk of economically usable logging residues, i.e. 88 percent, is produced in only three countries, i.e. China, Indonesia and Malaysia. While these three countries probably deserve most of the attention in terms of developing strategies for reducing and/or using logging residues, the figures for each country are only rough estimates. Chen (Appendix 1) estimated only 4.8 million m3 to be usable, which is slightly less than half the figure derived above (Table 7). Chen based his calculation on an assumed roundwood production of 47.95 million m3 while the FAO statistics indicated production of 101 million m3. Since China imposed harvesting restrictions recently, Chen's calculation appears to be more realistic.
Gintings and Roliadi (Appendix 2) distinguished between those residues generated during timber extraction in Indonesia (29.8 million m3) and those that were produced during the clearing of unproductive rubber and oil palm plantations (13.44 million m3). The figures in Table 7 suggest a total of 7.24 million m3 only for logging residues, which is almost 2.5 times higher than estimates by Gintings and Roliadi. There are two reasons for this discrepancy. First, the Indonesian authors based their calculations on a total log production of only 23.8 million m3, while FAO estimates production at 36.2 million m3 for 1998. Second, Gintings and Roliadi applied a residue factor of 1.25, as only 3.96 m3/ha of roundwood was estimated to be damaged during logging operations. As has been noted above, due to widespread illegal logging, actual log production is probably more than twice the level used by Gintings and Roliadi in making their estimates. Even the FAO statistics appear very conservative; thus it can be assumed that the volume of logging residues in the year 2000 is above 100 million m3. Hence, while it can be assumed that the total logging residue volume of the 15 selected Asian countries presented in Table 7 is a reasonable estimate, figures for individual countries may differ by as much as 50 to 100 percent.
A more important issue than precise estimation of residue volumes is what measures should be taken to reduce logging residues and make better use of those residues that cannot be avoided.
In terms of environmental and economic impacts, timber harvesting is usually the most significant aspect of forest operations and management. A considerable body of evidence indicates that forest harvesting operations can damage up to 50 percent of the residual stand (Sist et al., 1998), and even up to 60 percent as reported for Sabah, Malaysia (Tay et al., 2001). Damaged and destroyed trees contribute substantially to logging residues. As discussed above, in the Malaysian State of Terengganu two-thirds of logging residues consist of trees damaged or destroyed during road construction, logging and extraction (Andersen, 1999a). Lower logging intensities reduce damage and in the calculations of the previous section it was assumed that only half the logging residues are composed of damaged trees. It is obvious, however, that reducing the impact of forest harvesting could result in a significant reduction of logging residues. In comparison to conventional logging, applying reduced impact logging (RIL) techniques could probably reduce damage by about 50 percent (Pinard et al., 2000; Tay et al., 2001; Killmann et al., 2001), conserve soil and biodiversity, and help sustain the productive capacity of the residual forest after logging.
RIL can be defined as “intensively planned and carefully controlled implementation of harvesting operations to minimize the impact on forest stands and soils, usually in individual tree selection cutting” (Killmann et al., 2001). RIL emphasizes skills and commitment of forest workers to correctly apply a series of known technical guidelines. It is the application of the skills and efforts of well-trained forest planners, field rangers, supervisors, timber fellers, chokermen and tractor operators that determine the difference between conventional and best-management practices, i.e. differences in logging damage and residue volumes.
During most RIL operations, essentially the same volume of timber is extracted as during conventional cutting and yarding operations. In some cases, however, yields are reduced because less area is logged due to restrictions on tractor access to steep slopes (Tay et al., 2001).
RIL involves a number of distinct modifications to reduce logging damage. These include:
climber or liana cutting;
improved design of roads and skid trails;
tree identification and marking for directional felling;
pre-planning of skid trails;
improved road construction;
improved skidding and lower skid trail density;
removal of stream obstructions and drainage of skid trails;
rehabilitation of landings; and
maintenance of riparian buffer strips.
While RIL has largely been developed for existing ground-based tractor logging systems, it can be incorporated with cable and skyline systems or helicopter operations. This makes RIL practices some of the best options for sustainable forest management and reducing the current volumes of logging residues.
Although significant steps have been taken in the Asia-Pacific region to introduce RIL and other improved forest management practices,6 only a small forest area is currently benefiting from RIL. The main reason is that costs associated with RIL appear to outweigh benefits. While this is disputed by some studies (Holmes et al., 2001; Natadiwirya and Matikainen, 2001), the perception that RIL stands for “reduced income logging” persists. Furthermore, RIL requires significant efforts in training, capacity building and changes in die-hard habits.
6 In 1998, the APFC published the Code of Practice for Forest Harvesting in Asia-Pacific (FAO, 1998). In 2000, the APFC produced the Regional Strategy for Implementing the Code of Practice for Forest Harvesting in Asia-Pacific (APFC, 2000). Several countries and local administrations have developed forest harvesting codes or harvesting guidelines.
The adoption of RIL will reduce the volume of logging residues but will not eliminate them. Hence extraction and utilization of residues still have to be addressed. Loggers and the processing industry are only interested in a limited amount of recoverable residues. A number of basic questions have to be answered to assess what steps need to be taken to make better use of this underutilized raw material.
Which parts of the tree can be used?
When should they be extracted?
Who should extract residues?
What equipment is needed?
What are the costs (and benefits)?
What are current constraints?
Table 1 illustrates that on average (in Malaysia) about 58 percent of the tree is extracted; about 6.5 percent is left in the stump; about 14 percent is in top logs; various off-cuts make up 9 percent; and branches comprise about 14 percent. At present, potential users are interested mainly in the stump and the top logs. In addition, damaged trees of commercial species are also of interest.
The cutting of the excess stump would be the first step in minimizing logging residues, It should be part of the normal logging operations. Other activities could be performed during the original logging operations or at a later point in time.
The success of forest harvesting depends to a large degree on minimizing the damage to the residual stand that will make up the future crop. Even very careful logging has an impact on the residual stand, which cannot be avoided. Extracting logging residues would result in additional environmental impacts. However, this can be minimized by applying directional felling of damaged trees that may be without a crown (Thurland, 1999) and by conducting additional operations as soon as normal logging is completed. Minimizing environmental impacts is only one aspect of timing. Costs can also be reduced by re-entering the forest immediately after the normal logging, as existing roads and skid trails are still usable at that time.
Ideally, valuable residues are collected during the normal operations by the logging crews. This begs the question of why they are not already taking what others may consider valuable. There are a number of explanations for this. First, due to size limitations, many damaged and untagged trees have to remain in the forest; in some cases it could actually be illegal to remove them. Second, much of the material left behind is too small to be handled by the large, heavy equipment currently used by most operators. Such operators are not currently able to remove it cost-effectively. The alternative would be removal by a second crew with lighter and more flexible equipment.
Too big to be cost-effective
It is not economical using a big crawler tractor to extract 2 or 3 small pieces of residue logs using the 28 mm wire, as the efficiency is negatively affected.… The alternative is a second crew, specially trained, taking out residues as a special assignment, in a second operation immediately after extraction of the normal logs is completed.
Source: Andersen, 1999a
Extracting residues is costly, suggesting the need for lower royalty rates. This is another reason why alternative crews should be introduced. If original crews would be allowed to extract logging residues, they might be motivated to increase residue volumes with a concurrent decrease in normal logs extracted in order to qualify for reduced royalty rates. The result would be higher profits for them but would fail to meet the objective of improving forest management.
Andersen (1999a) concluded that logging residues could be handled by existing equipment but warned that efficiency was low and costs were too high, as current equipment used was dimensioned and fitted for felling and extracting large and heavy logs. He suggested smaller, faster, lighter and more flexible equipment including:
Lighter chainsaws (maximum 50 cm bar)
Smaller diameter cables (15–19 mm)
Smaller and faster-operating winches (60–90 m/min)
Smaller crawler tractors or rubber-tired skidders
Most logging contractors in the Asia-Pacific region rely on used equipment. Most of the logging equipment in Peninsular Malaysia is bought second-hand or made from used parts, except for chainsaws (Thurland, 1999). Some equipment is more than 40 years old. The situation in other countries is not much different. Even during favorable financial periods, investment in new logging equipment has been low. It reached a minimum during the recent financial crisis. Profit margins have been reduced and costs are scrutinized with even more care before investment decisions are made.
Very little research on the cost of increasing the utilization of logging residues has been conducted. Azizol et al. (1994, p. 7) observed that when their study was conducted, “the sale price could not even offset the extraction costs.” Havelund (1999) summarized his findings as follows (p. 297):
“The present variable cost of logging is estimated in the range of 38 – 49 RM/m3 (about US$ 10 to 13) ex logyard. Extraction of forest residues and small-dimension logs is expected to be more expensive. A conservative estimate gives variable logging costs in the range of 59 – 76 RM/m3 (about US$ 16 to 20) ex logyard as the costs of extracting the best 10 percent of the forest residues, which is equivalent of an additional 20 percent of the normal volume harvested.”
While alternative financial analyses may arrive at lower costs, in fact costs may even be higher if the expenses for retooling, purchasing new equipment and training are included in the calculations. In any case, the price of logging residues is very high relative to mill residues, which ranged from 12 to 20 RM/m3 (about US$ 3 to 5) in Malaysia during 1998 (Ravn, 1999b).
The transformation of the forest sector has taken place with unprecedented speed. Considerable investments have recently been made in the wood-processing sector, particularly in the wood-based manufacturing and pulp and paper facilities. Rubberwood has been transformed from waste material to a much sought after raw material (Balsiger et al., 2000). In some countries, mill residues are utilized to the extent that occasional shortages are reported. In response, wood processors have initiated their own plantation programs, with the pulp and paper sector taking the lead. Developments are so dynamic that it is also likely that interest in logging residues will increase in the future. However, there are numerous barriers that need to be lowered or eliminated to make logging residues more attractive. Innovative incentive schemes and royalty and fee schemes need to be developed, and premiums and other fixed costs kept at a minimum to reduce costs.
Habitual and attitudinal constraints should not be underestimated. RIL and extracting logging residues require a change of habits and perceptions. Good fellers and yarders are currently characterized by the size of their paychecks, which increase with the size of the trees they fell and yard (Havelund, 1999). The prevailing attitude is that anyone with a chainsaw can be a feller and anyone who can operate a bulldozer or crawler tractor can be a yarder. The results of such an attitude are low skill levels, not only confined to workers but include contractors and forest agency staff. In fact, the majority of people working in the forest lack basic understanding of sustainable forest management, a constraint that will continue as long as there is inadequate training for forest workers and contractors. Appropriate training courses need to be offered together with adequate income compensation systems so that trained participants do not experience a loss of income.
A lack of clear guidelines and poor supervision are additional constraints that need to be overcome. These are probably the easiest to tackle for forestry agencies. Legislative and administrative constraints need to be eliminated by introducing more flexible rules. It should be possible to extract accidentally cut and heavily damaged trees. However, this requires a relationship of trust between foresters and loggers. Foresters need to increase their presence in the forest during logging operations. They need to take their supervisory role more seriously and spend more time in the forests to deal with day-to-day problems. Increased interaction in the field will facilitate the extraction of logging residues (Havelund, 1999). Cutting limits need to be reviewed and current license agreements need to be amended.
There is still a considerable lack of solid research results to make a case for the increased utilization of logging residues. The limited research results that are available should stimulate forest agencies to review their guidelines, to assess the marketing situation for logging residues, and to initiate concerted training efforts.