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Lesser-known tropical wood species: How bright is their future?

Freezaillah B.C. Yeom

Freezaillah B.C. Yeom is Assistant Director-General of Forestry, Peninsular Malaysia.

One of the crucial questions in tropical-forest management today is the future of lesser-known species. Hundreds of potentially valuable trees are being left behind - often simply to be burnt in forest clearing operations like logging, agricultural conversions and dam building. Little is known at present about their possible end-uses or even their physical properties. There is thus considerable debate over what to do about them. Should research, planning and investment be undertaken to find uses for them, as Freezaillah B.C. Yeom argues in this article? Or, by contrast, should they be cleared away as quickly as possible and replaced by plantations, as James S. Bethel argues in the article that follows?

1. Resource utilization and wood marketing

As a renewable natural resource, tropical forests are unique in their structural complexity, which arises from the existence of a wealth of species with diverse silvicultural characteristics and wood properties. Implicit in this very fact, however, are problems in the utilization of such a varied and variable mixture of wood species. Naturally, over time, a scale of preference has developed. Some species are in high demand, while others are merely acceptable. At the other end, however, is a large number of species broadly and variously called "lesser-known species", "secondary species", "unpopular species", "non-obligatory species" and "weed species". In this article, such species are termed "lesser-known species", or "LKS".

It would be simple to define an LKS as a commercially less accepted species left in the forest after a logging operation. But, as stated by Hansom (1983), a better definition is that it is a species that is not being put to best advantage (although many commercial species are not being put to best advantage either). The list of usable species has lengthened to some extent because of advances in technology and promotion and because of a growing scarcity of the more desired species. While the domestic market - understandably - is less discriminating than the export market, only a small number of potentially usable species are nonetheless generally utilized.

There has been considerable discussion about the fuller utilization of tropical forests with particular reference to the LKS, but the problem has remained intractable and little can apparently be done. Eddowes (1980), in discussing the technical aspects of promoting the LKS in Papua New Guinea, identified the following problems:

· difficulty in the identification of timber species;
· inadequate data on physical and mechanical properties;
· incorrect marketing into wrong end-uses;
· irregular or inadequate supplies;
· poor grading.

These problems, however, apply to LKS not only in Papua New Guinea but in all closed tropical forests. Moreover, even if problems such as these are overcome, fundamental questions about the LKS must still be answered: (1) Will there be sufficient future demand for LKS - either domestically or on the export market - to justify the additional research and investment that their utilization will entail? and (2) To what degree can there be extensive increases in the harvesting of LKS before unacceptable levels of environmental damage occur?

Table 1. Total growing stock estimated an end of 1980 for both broad-leaved and coniferous wood (In millions of cubic metres)










America (23 countries)







Africa (37 countries)







Asia (16 countries)







Total (76 countries)







Source: FAO/UNEP, 1982.

Table 2. Gross volumes and commercial timber removal from undisturbed productive closed hardwood forests (In cubic metres per hectare)


Gross volume

Volume removed

Apparent content of LKS


















Source: FAO/UNEP, 1982.

Utilization potential

Lesser-known species and small-sized trees, which are included in the gross volumes shown in Table 1, are not currently of commercial importance. Table 2 indicates the gross volumes and commercial out-turn of timber from undisturbed productive hardwood forests only. It can be seen that from this class of forests, commercial out-turn is extremely low. An average of only about 5 percent of the total timber volume is removed in logging operations in American and African tropical forests. Asian forests, which are richer in commercial species because of the dominance of the family Dipterocarpaceae, give higher yields - about 14 percent.

In tropical countries, increased production will come from less accessible areas and from forests in difficult terrain. In addition, LKS and small-dimension trees will also be increasingly removed in logging operations, thereby contributing to production increases. If demand from developed countries were to be stronger than the FAO (1982) projections, then exports of saw and veneer logs, plywood and perhaps also sawnwood might be insufficient with existing production and trade flows. However, it is anticipated that tropical countries in America will be able to satisfy the internal demand and, in all probability, to increase production to meet the export demand as well (Marchand, 1983). Currently, annual exports of tropical timber amount to about 73 million m³ of logs and other products. Even allowing for increases in domestic consumption and export demand, the annual requirement can be considered relatively small in relation to existing tropical timber resources.

Asian forests The total growing stock from productive forests in Asia at the end of 1980 was estimated at more than 31000 million m³ of which more than 3000 million m³ were of commercial importance in accordance with existing standards of utilization. It may be concluded that in the short and medium term the region is not about to experience a timber crisis, even allowing for anticipated increases in domestic consumption and export demands. Added to this is the fact that the large resources in South America are as yet hardly touched. Importers, therefore, have little difficulty in obtaining logs or timber products of choice quality. If supplies prove scarce in one country because of resource depletion, a ban on log exports, or higher costs, there is always an alternative supply, at least in the short and medium term. When the Philippines, which was a major log exporter, faced dwindling log supplies coupled with a log ban, Malaysia and Indonesia came to the fore. With Indonesia now banning log exports and promoting primary processing, the pressure is on Sarawak and Papua New Guinea to meet the demand (Bell, 1982). If regional supplies cannot be obtained, there are other sources in South America and Africa that could be tapped.

THE VAST TROPICAL FOREST - research on hundreds of species is needed

Problems Most developing countries in the tropics have balance-of-payments problems. This fact, coupled with the need for foreign exchange to finance development projects, means that it is not too difficult for them to be persuaded to open more forest areas in order to export logs or processed products. Thus, the most likely scenario within the foreseeable future is that logs and other wood products of prime quality will continue to flow from the tropics to the consumers. It will take many years before hardwood-log supplies from the region are curtailed to a very significant degree (ESCAP, 1981). When one can pick and choose in this way, there is naturally little or no interest in the LKS as far as the consuming countries are concerned.

Also of importance is the fact that industries in developed countries are capital-intensive, automated and sufficiently large to enjoy economies of scale. Under such circumstances, raw materials that are as close to uniform in size and quality as possible are important. Processing of the LKS usually means utilization of a mixture of species, since most of these separate timbers are not available in large enough volumes to justify individual processing. Unit production costs will probably be affected by smaller production runs, higher inventory costs, additional sorting requirements, more complicated production controls, and minor processing problems requiring knowledge of timber properties and hence the modification of processing parameters (Groome and Associates, 1981). Problems encountered may result in frequent and expensive shut-downs for retooling and other adjustments. For adequate retooling, it may even be the case that heavy investments will be necessary. Thus the LKS, covering a varied and variable mixture of species, will impose severe constraints on the smooth functioning of processing schedules. Under the circumstances, it is difficult to see how consumers can be persuaded to use them, especially when supplies of normal raw materials are still generally adequate.

As timber resources become scarcer, however, and the real prices of prime species rise, the LKS and small-sized logs will gain wider acceptance and thus graduate into the marketable group. Leslie (1977) concluded that time, to some extent, tends to ease the problem of the LKS almost by itself. This is particularly well illustrated in the utilization pattern for domestic consumption. The tropical forests in north Queensland, Australia, for instance, are rich in tree species. At the end of the last century, during the time of settlement and large-scale agri-conversion of forest lands, only one species, red cedar (Toona australis), was processed for consumption. By 1900, some 10 species were in use. By 1930, when scarcity began to be felt, another 20 species were added. With the development of the sawmilling industry and the growth in demand during the 1941-1945 war years, there was a dramatic increase in the number of species used. At that time sawmills and plywood mills were processing over 100 species of tropical wood.

In Malaysia The importance of the home market in the utilization of the LKS in a situation of dwindling forest resources and a well-developed timber industry is further illustrated by the experience in Peninsular Malaysia. Here there are 38 plywood/veneer mills and 644 sawmills processing logs, both for export and for an expanding domestic market. Although there are local shortages of logs, supplies are generally adequate. However, it is projected that shortages will be experienced toward the end of this century. Thus, Peninsular Malaysia is now beginning to bypass the utilization problems of the LKS: choice species are exported while LKS are mainly sold in the home market. This development is well illustrated by examining the log intake of sawmills and plywood mills in Terengganu, one of the east-coast states.

Timber species here have been classified into three main hardwood groups: heavy, medium and light hardwood. Species in each group are enumerated. However, with forecasts of declining forest resources, an increasing volume of other light hardwoods is now being used, consisting of a mixed bag of LKS of unidentified species. As shown in Table 3, the utilization of this group more than doubled during the five-year period between 1977 and 1981. This increase is entirely the result of increased use of the LKS. In 1982, it is estimated, the LKS accounted for about 12.5 percent of the total log intake of sawmills in Peninsular Malaysia. The LKS intake of plywood/veneer mills was even higher: 27.5 percent (Ong and Chew, 1983). It has to be stressed that fuller utilization of the LKS is possible in the case of Peninsular Malaysia only because of the presence of a well-developed log-processing industry coupled with a relatively sizeable local market. The situation is quite different with Sabah and Sarawak, where domestic consumption is small and forest industries are not well developed.

Promotion of lesser-known species

Present market conditions are not conducive to the utilization of the LKS, especially in the following cases:

· agri-conversion and related development of forested land;

· inundation of forested land due to construction of dams;

· conversion of natural forests into forest plantations;

· low logging out-turn, particularly in many tropical American (8.4 m³ per ha) and African (13.5 m³ per ha) countries.

Undoubtedly, it is in the first three cases above that wastage is most serious. Where forests are being clear-felled for agricultural and forest-plantation development, the LKS and ail other vegetation are burnt for site preparation. Apart from pollution impacts, this also results in lost opportunities for socio-economic development. Because of population and other pressures in many tropical countries, forests are continually being converted to agriculture. It is estimated that during 1979-1980, nearly 1.4 million ha of productive natural forests were deforested and the land converted to some form of agricultural and other uses in Southeast Asia and the western Pacific region (FAO, 1983a). In Malaysia, some 81000 ha of forests were cleared annually for the cultivation of crops during the 1970s, and this trend is expected to continue for the next decade (Arshad, 1979). In Indonesia, the transmigration programme is targeted to resettle 5 million people, mainly in Irian Jaya, under the current five-year development plan (Hastings, 1983). Such a programme will involve the conversion of large tracts of forest land into agriculture and settlement.

It is evident that in cases such as these, fuller utilization of the LKS is highly desirable and the potential is enormous.

Wood chips Prospects are now increasingly favourable for the utilization of the LKS in their disintegrated form as chips and particles. The wood-chip trade is a large and growing market. Total world exports amounted to more than 18 million m³ in 1981, but most of these are from and to developed countries and involve only softwood chips (FAO, 1983b). Export of tropical wood chips in Malaysia began in the 1960s with chips from old rubber trees, dipterocarp mill residues and mangroves to meet the requirements of the pulp industry in Japan. The first shipment of mixed tropical hardwood or LKS was shipped from Papua New Guinea to Japan in 1974. Table 4 indicates the volumes exported for the five-year period 1977-1981. The export of wood chips from Papua New Guinea is truly an important milestone in the utilization of LKS. It is the result of a clear-felling operation. Prime species are sawn and all other logs, irrespective of species, size and form, are chipped and exported. About 70 percent of the volume is composed of 40-50 main genera and no one species exceeds 6 percent of the standing volume (Fenton, 1982). About 200 different tree species occur in the area.

The export of chips from Papua New Guinea is operated by JANT Pty. Ltd., which is almost wholly owned by Honshu Paper Co., Ltd., of Japan. The company has a concession area of 85400 ha near Madang. The original objective of this project was to generate sufficient cash flow through the sale of chips to replace the felled forest with fast-growing plantations which could increase production by from three to five times. The annual cut is about 4000 ha. However, the reforestation effort has not kept up with the rate of exploitation, apparently because of problems of land tenure. Plantations established with species such as Eucalyptus deglupta and Terminalia brassii are fast-growing and appear successful. In 1977, the Gogol Reforestation Co., a joint venture between the Government of Papua New Guinea and JANT Pty. Ltd., began strengthening reforestation operations. By the end of 1982, some 2711 ha were planted.

In the Madang project, most areas abandoned after clear-felling obtained complete cover within a year. In fact, the vegetation cover was 1-2 m high after only six months (Cavanaugh, 1975). Similar areas exploited several years earlier appear as thickets of Macaranga with some Anthocephalus chinensis bordering roadsides and open areas. Clear-felling also raised the water-table (Fenton, 1982). The productivity and value of the new growth within the foreseeable future are doubtful. If the original objective to replace exploited areas with high-yielding forest plantations is attained, the Madang chip project is highly commendable. However, this effort has not yet been entirely successful. It was for such reasons that Richardson (1977) argued very strongly against such wood-chip projects and cautioned: "Our excitement must be tempered by awareness of some possible deleterious (even disastrous) consequences of uninhibited forest clearance in some tropical areas."

Table 3. Log intake of sawmills and plywood mills in Terengganu, 1977-1981

Total log intake

Other light hardwoods

Other light hardwoods as percentage of total

(thousands of cubic metres)





















Table 4. Exports of wood chips (In thousands of cubic metres)













715 a

498 a

282 a

301 a

301 a

Other Far East countries (mainly Papua New Guinea)






Source: FAO, 1983b.
a. FAO estimate.

Fuller utilization of lesser-known species is possible in the case of Peninsular Malaysia only because of the presence of a well-developed log-processing industry and a relatively sizeable local market.

2. Forest ecology and development

The number of species in tropical forests is larger than in any other plant community, ranging from 2000 to 3000 among larger trees alone. The tropical forests in Southeast Asia are considered to be the most luxuriant in this respect, with an estimated 2500 species, of which 700 are known to reach timber size of at least 1.34-m girth (Whitmore, 1975). In South American tropical forests, at least 470 tree species are either of commercial importance or of potential commercial importance (FAO, 1976).

In spite of the wealth of tree species in tropical forests in Asia compared with those in South America, the forest resources in Asia are less heterogeneous, owing to the phenomenon of family dominance. Tree species belonging to the Dipterocarpaceae family are generally very dominant in tropical forests of Asia from Sri Lanka to the Philippines and the island of Borneo. This feature is less marked but nevertheless evident for the Meliaceae and Sterculiaceae in some African forests and the Leguminosae in South American forests. In Borneo, 270 species of dipterocarp are known, with perhaps more to be discovered (Symington, 1974; Whitmore, 1975). It is because of this phenomenon that the dipterocarp content of some Asian forests may exceed 80 percent of the timber yield and make them more productive commercially than forests in South America. The forests in tropical Africa occupy an intermediate position in this respect from the point of view of utilization.

Tropical forests are structured vertically and several strata are recognized. Typically, the mixed dipterocarp forests of Asia in Indonesia, the Philippines and Malaysia may be characterized by the following stratification of tree vegetation:

· emergent trees which can attain heights of 60 m with their isolated crowns protruding from the general canopy level - crowns of these emergent trees may exceed 18 m in diameter;

· a fairly continuous main canopy consisting of dominant and co-dominant trees that are generally about 45 m high;

· a layer of trees with canopies at about 25 m;

· other vegetation consisting of shrubs, stemless palms, etc.

Another important component of tropical forests is thick-stemmed woody creepers, climbers, lianas or vines. These climbers grow to the canopy top and often have crowns the size of tree crowns. Tree crowns are often physically interlinked with these massive crowns. In a study of Malaysian dipterocarp forest, Appanah and Putz (1983) reported the occurrence of 376 climbers per ha with stem diameters greater than 2 cm. Of this total, 113 had stems with diameters bigger than 5 cm. Some 25 species of climbers were identified in this study.

In timber liquidation projects, the overriding consideration is the maximum utilization of the available timber resources, including the LKS, to prevent wastage. However, in forests managed for timber production, forest management must ensure sustained yield and long-term timber productivity through controlled harvesting and forest-resource development operations. These are important aspects of natural-forest management for which the role of the LKS must be critically examined.

With low levels of management and inadequate supervision, tropical forests, in most cases, are exploited rather than harvested. There is little follow-up treatment in terms of forest development through the establishment of plantations or silvicultural operations. By and large, exploitation occurs through extensive management based on felling limits or selective felling. Timber is a high-bulk commodity necessitating road construction and the use of heavy machinery for transportation, and it is generally true that logging operations in tropical forests use powerful machines inefficiently without proper logging plans. When this is coupled with inadequate control and wet weather, serious damage can be done to soil and to the residual trees needed for the next timber crop.

CREEPERS, CLIMBERS AND LIANAS - problem causers in tropical logging (a)

The impact of logging

Assuming market acceptance of LKS, a fundamental question is whether their out-turn can be increased without impairing long-term productivity. Rao (1982) and others have warned that scientific information on this question is limited, but that available evidence indicates serious damage to the ecosystem under intensive logging. The nature and extent of the damage needs critical evaluation, so that indications of the increased damage resulting from the inclusion of the LKS in logging operations can be determined.

CREEPERS, CLIMBERS AND LIANAS - problem causers in tropical logging (b)

Compared with that in other countries, logging in Malaysia and the Philippines is extremely heavy, with production at about 45 m³ per ha in Peninsular Malaysia, 75 m³ per ha in Sarawak and 90 m³ per ha in both Sabah and the Philippines. Observations on the impact of logging in Malaysia and elsewhere indicate that damage is mainly caused by felling, extraction and road-building. Marn and Jonkers (1982) examined the impact of normal logging on the residual trees and soil conditions in mixed dipterocarp forests in Sarawak. Timber removal was 53 m³ per ha with the removal of about 13 trees per ha. Data on the damage to residual trees by diameter classes are presented in Table 5. Damage is extensive, with about 50 percent of residual crop trees uprooted, broken and injured. Burgess (1971) also reported felling damage of this order in Peninsular Malaysia. Studies in Sabah indicated even heavier damage, with only 34 percent of the residual crop undamaged or only slightly damaged; but here timber out-turn was much higher, at 89 m³ per ha (Fox, 1968a).

Table 5. Residual trees sustaining damage per hectare of Sarawak mixed dipterocarp forest

Diameter (cm)



Complete trees




























Source: Marn & Jonkers, 1982.

Table 6. Logging damage in lowland dipterocarp forests in East Kalimantan, Indonesia

Tree condition


Percentage of total




Crown damage



Branch damage






Source: Abdulhadi, Kartawinata & Sukardjo, 1981.

Table 7. Role of climbers in logging damage in one-hectare plots

Treated plot

Control plot

Neighbouring trees knocked down or pulled over by felled trees



Trees with crown damage



Trees with bark damage with bark removed at least 0.3 m long



Source: Appanah & Putz, 1983.

Table 8. Net growth rate of residual stand as a function of logging severity for eight plots in logged-over mixed dipterocarp forest in East Kalimantan, Indonesia

Logging severity (percentage)

Years after logging

Net growth

























Source: Miller, 1981.

Table 6 summarizes the findings of studies on the effects of mechanized logging in lowland dipterocarp forests in East Kalimantan, Indonesia (Abdulhadi, Kartawinata and Sukardjo, 1981). This study shows that with the extraction of 11 trees per ha, about 40 percent of the residual trees suffered branch and crown damage. Apparently, logging damage to residual trees is of the order of 40 to 66 percent.

Trees felled are usually either emergents or main canopy trees with large crowns about 18 m in diameter. In addition, their crowns are often physically interlinked with the crowns of climbers and other trees, which could be equally massive. When felled, such trees can smash up a considerable number of others in the lower canopies, giving rise to various categories of damage. Therefore, climber-cutting is recommended prior to logging (Fox, 1968b; 1972).

Removal of more trees in the emergent and main canopies may be assumed to increase damage to the residual stand because of the greater volume felled and the greater number of climbers affected. However, felling of smaller trees in the lower canopy may not be quite so damaging, because their crowns are much smaller and because of the lesser incidence of climbers on such trees. The role of climbers in felling damage to the residual stand is well demonstrated by recent studies in a mixed Shorea-Dipterocarpus forest in Peninsular Malaysia (Appanah and Putz, 1983). Damage is recorded for all trees larger than 10 cm in diameter (Table 7). It can be seen that climbers greatly increased damage by pulling and breaking down neighbouring trees. However, the number of other trees with damaged crowns and bark in the treated plots did not appear to be different from that in the control plots.

Soil damage

Soil damage through erosion and compaction is another serious logging impact that could impair forest productivity. It is caused by the construction of various categories of roads, including main roads, secondary roads and feeder roads, all of which involve scraping off the topsoil and soil compaction. After felling, trees are cross-cut, hitched to a bulldozer and dragged along the ground to collection points or landings for loading on lorries. This operation adds further to soil disturbance and compaction. Logging arches can reduce such damage, but they are, apparently, rarely used. Much of the tractor damage is caused by the use of the blade as a counterbalance to log weight. The average width of skid trails is about 5 m, and the network of such trails fanning out from landings results in still more damage. Landing areas with tractor yarding are generally of about 0.2 to 0.6 ha, and, according to observations in Sabah (Fox, 1968c), there may be one or more landings in each felling block. On such bare ground in Kalimantan, the soil has lost its structure and become extremely compacted, thereby adversely affecting water infiltration. It was shown that water infiltration in disturbed soil is about seven times slower than that in the undisturbed area. This is certain to increase surface run-off and erosion.

It is thus extremely difficult to generalize a threshold value for timber removal beyond which residual stand and soil damage will impair forest productivity. However, observations in Malaysia indicate that current levels of damage may well represent a general upper limit resulting from the removal of about 50-90 m³ per ha. Under such conditions, it may be generally concluded that the added harvesting of the LKS will cause this threshold to be exceeded, thereby impairing forest productivity and the sustainability of all forms of forest produce, both tangible and intangible.

Canopy openings Apart from damage to soil and residual stands, greater canopy openings resulting from the removal of the LKS can result in other management problems. In Malaysia, for example, where the stemless palm (Eugeissona triste) and bamboos are endemic, they can, with too much crown opening, spread extremely rapidly and affect regeneration. Their eradication is both difficult and costly. In preliminary trials, Chin (1979) showed the effect of various cutting regimes and reported that certain species of bamboos respond immediately to canopy opening by producing new culms. Certain creepers also invade areas with heavy crown removal and may prove injurious to recruitment, survival and natural regeneration. The appearance of dense populations of climbers and nomad trees in areas where the soil is exposed to the sun or where the topsoil is removed results in extreme competition, as reported in Sabah by Meijer (1970). Weed species also become dominant after logging in Kalimantan, and such climber species as Merremia peltata and Mikania scandens frequently overgrow and smother seedlings and saplings (Abdulhadi, Kartawinata and Sukardjo, 1981). After intensive logging in the Solomon Islands, the climber, Merremia sp., adversely affected the growth and development of tree regeneration.

In a recent paper, Smits (1983) reported that ectotrophic mycorrhiza is important in the growth and development of certain dipterocarp tree species. The death of dipterocarp seedlings after intensive logging may be related to the increase in soil temperatures after excessive opening of the canopy. These temperatures were found to approach lethal values of the fungi concerned.

The threshold for logging

It is obvious that logging affects tropical forests in many different ways and that most of these effects are still unknown to us. Reviewing the processes and cycles in tropical rain forests, Whitmore (1981) concluded that while there is general consensus on the characteristics of regrowth species after disturbance, there is none on the impacts of forest clearance on the hydrological and mineral cycles and on biomass recovery. No proper or systematic studies have yet been undertaken to relate logging intensity to the growth of residual stands. Estimates of average growth on logged-over plots are complicated by logging methods, forest and soil types, and a host of other factors, apart from logging intensity. However, there appear to be indications of an inverse relationship between logging severity and the resulting net growth of the residual stand in Kalimantan, as shown in Table 8. Logging severity is defined as the percentage of trees cut, damaged and destroyed during logging.

What is the threshold for logging? The review and discussions above suggest that it may be of the order of 50-90 m³ per ha, a figure that coincides with the current rate of logging in Malaysia and the Philippines. Removal of the LKS will increase out-turn substantially and exceed this vital threshold, resulting in unacceptable levels of logging damage. Viewed within this broad management perspective, the current non-utilization of the LKS is perhaps a blessing in disguise in many Asian countries. However, in other countries - particularly those in tropical America and Africa - where commercial out-turn is low, ecological problems arising from harvesting increased volumes of LKS are generally of less concern. Here a fuller utilization of the forest is warranted in order to improve socioeconomic benefits from the forest wealth and also for reinvestment into forest resource and infrastructure development.

Operational procedure for the complete use of the mixed tropical forest

3. Action programme

Much has been written and said about the utilization of the LKS, but progress has been both slow and insignificant. However, there are compelling reasons why this problem should be accorded the utmost priority. Each component of the problem has to be identified and systematically assessed to obtain an overall perspective for the formulation of strategies. Obviously, the resources and expertise needed are beyond the present capability of most developing countries. International cooperation and assistance is thus urgently required.

The figure outlines an operational procedure to approach the various stages involved in promoting the utilization of the LKS (Brazier, 1978). The first stage is to group the LKS into species of abundant and sparse occurrence. The non-utilization of the abundant species is normally indicative of either technical difficulties or the fact that the species are of poor stem form. Those with technical constraints need careful evaluation in order to select and promote for specific end-uses, while LKS with poor stem form could be evaluated and promoted as dimension stock, among other things. Sparse LKS have to be studied with a view to grouping and promoting them for specific end-uses. At the lower end of the utilization chain, LKS are used as raw material for pulp and board products based on wood chips and, lastly, as fuelwood.

Resource base Information on the resource base, inputs from research and development, systematic and aggressive marketing and, above all, cooperation between consumers and producers are vital and implicit in the steps to be taken. Certainly there is a need for adequate knowledge and information about the resource base in order to be able to classify the LKS into abundant and sparse species. The quantitative separation of these two groups is difficult to define, but availability- of about 1000 m³ per year has been, suggested as a possible dividing line (FAO, 1976). In addition, the inventory data should indicate total volumes to facilitate subsequent promotion and marketing - for which continuity of supplies at predictable rates must be assured. This has always been singled out as a major problem with the LKS.

Properties Data on the technical and other properties of wood are fundamental to the promotion of the LKS. Evaluation of wood properties may be undertaken in stages. The initial stage can be confined to determination of density, colour and any special features of a given wood species. During this stage, measurements may be undertaken on wood specimens from limited sampling. A wider range of properties is identified during the second stage, including additional characteristics such as strength and sawing, drying and peeling properties. Pulping trials may also be usefully included during the second stage. The final stage of full-scale testing is often undertaken on samples adequate to cover the complete range of the species' distribution.

The samples thus collected and authenticated are subjected to tests to determine their properties. Much of what is needed for local utilization on a mixed basis is covered by the first stage; for export or for specialized uses, the other two stages are needed. In the evaluation of use properties and commercial acceptance for the marketing of tropical wood, Erfurth and Rusche (FAO, 1976) examined various characteristics, including density, workability, shrinkage, finishing, strength, durability and log form.

End-use grouping As noted by various authors, the biggest potential for the LKS is in marketing by end-use grouping rather than by species. Such an approach provides a product rather than a species focus. Marketing of timber by groups rather than by species is by no means a new concept. Of a total of about 3000 tree species in Peninsular Malaysia, for example, 677 are exploitable for timber utilization. Of these, 408 have been introduced to the international markets through the Malaysian Grading Rules. These 408 timber species are divided into 53 timber groups and marketed on a "single-grouping" basis under such names as "dark-red Meranti". The remaining 269 species are at present marketed as "mixed light hardwood".

But marketing these 269 species is problematic, as they cover a wide and diverse range of properties (Tong, 1983). To overcome these problems, property requirements for end-uses are vital. An end-use classification defines significant properties in qualitative and quantitative terms for each type of timber product, so that timbers meeting such requirements can be expected to give a satisfactory performance (Brazier and Webster, 1977). Timbers with roughly equivalent properties can thus be grouped and marketed together for a particular end-use.

In the utilization of the LKS through grouping, the single most important end-use is structural application. Here grouping, or the establishment of strength classes, has the most potential for the utilization of the LKS because of overall simplification (Keating, 1981). This is because it is possible to develop methods for grouping by mechanical stress grading with no reference to the species. In Peninsular Malaysia, Tong (1983) identified the housing and construction industry as the one with the greatest potential for LKS because timber is utilized mainly for structural purposes. Here, strength properties are an overriding consideration, as against colour or grain. In fact, the housing sector is already utilizing quite large quantities of the LKS. In low-cost housing projects, where price is a major consideration, users will be more willing to try the less expensive LKS, provided that they are technically sound. Further research and development to develop and formulate mechanical grading techniques, grades, specifications and nomenclature in this sphere would appear to be one of the most promising approaches to promote the utilization of the LKS, especially for the home market.

Construction is the industry with the greatest potential for utilization of the lesser-known species.

It is extremely difficult to generalize a threshold value for timber removal beyond which residual stand and soil damage will impair forest productivity.

Papers/panels Another important area of development with enormous potential is the use of the LKS for paper and panel products, as emphasized by Youngs (1977). Wood chips of the LKS are now already being exported to Japan from Papua New Guinea. But prices are low. Mixed light hardwoods and laun (dipterocarp) chips obtained, respectively, 86 percent and 38 percent of the prices of Australian eucalypts (Fenton, 1982). With such a rich mixture of species, chips from LKS are not preferred and thus do not fetch good prices. To date, 72 species from 35 families of the LKS in Malaysia have been studied in pulping trials. An analysis of all the results indicates that all the low-density species (250-450 kg per m³) had good strength properties. Not a single species could be considered poor for pulping. In the medium-density group (451-650 kg per m³), about 50 percent of the species gave good or satisfactory results for pulping (Peh and Khoo, 1983). With improved techniques through greater research and development efforts, chips from LKS may yield quality pulp or panel products that would improve prices sufficiently to justify their utilization.

Marketing There is strong opinion that the major problem of the LKS is not technical, but lies in the marketing area. Dynamic, aggressive and resourceful attitudes will have to be built up to sell the LKS. The marketing of tropical timber involves a series of activities such as collecting, producing, grading, sorting, storing and transporting the product and contacting the client, all leading to the ultimate goal: effecting a sale. In an excellent study, Wassink and Wiselius (1979) stressed the more important issue of marketing tropical timber, including the problems of introducing new species. Hansom (1983) also discussed various aspects of industrial marketing of forest products and emphasized the need for LKS to have a price advantage over species with similar properties, particularly through marginal pricing. Utilization of the LKS will enhance yields per hectare and this can be expected to reduce logging costs to a certain extent. Since logs feature prominently in the export of forest products, it has been suggested that log-exporting policies be modified to promote the marketing of LKS logs (Groome and Associates, 1981). Where log-export restrictions are implemented or considered, a selective promotional approach may be adopted, as in Peninsular Malaysia in 1972.

To increase utilization of the LKS in the ASEAN region, Groome and Associates recommended that local processors be encouraged to produce and promote finished products and components made from LKS. In this way, possible problems in sawing, peeling, seasoning, machining, gluing and pre-finishing would become the responsibility of the manufacturer, whose continued well-being depends on finding solutions to such problems. The owners and processors in developing countries are always more interested in new sources and species of local raw materials than are industries in developed countries, which can easily tap other new sources for imported raw materials.

Obviously, there are no simple answers for improving the utilization of the LKS. Cooperation and understanding between consumers and producers are indeed vital. There is also a great need for inter-regional cooperation among consumers. The main problem to overcome is a psychological one: competitors, clients and the backstopping industry must not be regarded as adverse entities - as they are at present.

EROSION IN AMAZONIA - forest development must protect soil


The utilization of the LKS has now been identified as one of the major problems to which the international forestry community must address itself. In many ways, the elements of trade and development are essential to the whole question of LKS utilization and must be given equal priority and importance in the development of tropical forest resources. In this respect, the advanced negotiations concerning the establishment of the International Tropical Timber Organization, as part of UNCTAD's Integrated Programme for Commodities, offer much hope for the future of tropical forestry. These negotiations cover four elements: research and development; market intelligence; reforestation and forest management; and increased and further processing in producing countries. This package consists of both trade and development aspects, and substantial agreement has been reached between consumers and producers of tropical timber.

Since up to 93 percent of tropical forest volume consists of LKS, and since many LKS are at present being burnt or otherwise wasted after logging operations, agricultural conversion projects (including shifting cultivation), hydroelectric construction projects and conversions of the natural forest into plantations, the need to utilize them more advantageously is obvious. This is especially true in many countries in Latin America and Africa, where present logging volumes are low and where the harvesting of LKS can therefore aid social and economic development without causing environmental damage. In certain parts of Asia, however, where logging is already intensive, increased harvesting of LKS could cause environmental damage.

However, the demand outlook for LKS, at least in the short term, is not particularly bright: (1) importing countries are unlikely to buy LKS as long as supplies of currently preferred species remain stable; (2) local demand for LKS can exist only where a domestic market and a domestic processing capacity also exist; and (3) while LKS may be marketable as chips, the social and environmental costs of such operations may be unacceptable.

Therefore, where logging intensity is already high, encouraging the increased exploitation of LKS may be unwise, at least until better harvesting techniques and controls are employed and new markets are developed. Where logging intensity is still low, LKS are a good potential source of wood. In these areas, there is a need to develop an action strategy that includes both the acquisition of new information on species characteristics and the implementation of new marketing strategies. Within these limits, the immediate future of lesser-known species is comparatively bright, although not entirely sunny. There are definitely some clouds in the sky.

LOGGING OPERATION IN MALAYSIA - can lesser-known species be marketed?



Effects of mechanised logging in the lowland dipterocarp forest at Lempake, East Kalimantan. Malay. Forester, 44.

APPANAH, S. & PUTZ, F.E. 1983

Climber abundance in virgin dipterocarp forest and the effect of pre-felling climber cutting on logging damage. Malay. Forester (in press)

ARSHAD, A. 1979

National agricultural policy and its implications on forest development in the country. Malay. Forester, 42.

BELL, G.S. 1982

Forestry development corporations in Papua New Guinea. Commonw. For. Rev., 61.

BRAZIER, J.B. 1978

Complete integrated utilization of tropical forests. Paper presented at 8th World Forestry Congress, Jakarta.


Timber standards based on end use. Unasylva (FAO), 29 (117): 15-19

BURGESS, P.F. 1971

Effect of logging on hill dipterocarp forests. Malayan Nature Journal, 24.


The Gogol wood chip project. Paper presented at Symposium on Ecological Effects of Increasing Human Activities on Tropical and Sub tropical Forest Ecosystems, University of Papua New Guinea, 28 April-1 May 1975. Publication 3, Australian Committee for Man and Biosphere.

CHIN, T.Y. 1979

Effects of cutting regimes on bamboo infested forest areas. Forestry Department, Kuala Lumpur (unpublished report).

EDDOWES, P.J. 1980

Technical aspects of marketing unfamiliar species. Paper presented at 11th Commonw. For Conf., Trinidad and Tobago

ESCAP. 1981

Subregional/regional co-operative measures to improve marketing of tropical timber and timber products, by B.F. Sanvictores. Bangkok

FAO. 1976

The marketing of tropical wood: wood species from South American tropical moist forests by T. Erfurth & H. Rusche. Rome.

FAO. 1982

World forest products: demand and supply, 1990 and 2000. Rome. FAO Forestry Paper 29.

FAO. 1983a

Trends in wood and wood products. Production and trade. Southeast Asia and Western Pacific. FO: RAS/78/010. Kuala Lumpur. Asia and Pacific Forest Industries Development Group, Discussion paper 3.

FAO. 1983b

Yearbook of forest products 1970-1981. Rome. FAO Forestry Series 16 FAO Statistics Series 44.

FAO/UNEP. 1982

Tropical forest resources. Rome. FAO Forestry Paper 30.

FENTON, R. 1982

International wood-chip trade (and the South Pacific). Commonw. For. Rev., 61.

FOX, J.E.D. 1968a

Logging damage and the influence of climber cutting in the lowland dipterocarp forests in Sabah. Malay. Forester, 31.

FOX, J.E.D. 1968b

Defect damage and wastage. Malay. Forester, 31.

FOX, J.E.D. 1968c

The soil damage factor in present day logging in Sabah. In Proceedings, Third Soils Conference. Department of Agriculture Kuala Lumpur.

FOX, J.E.D. 1972

The natural vegetation of Sabah and natural regeneration of the dipterocarp forests. Ph.D. thesis University College of Wales, Bangor, UK.


End use survey of ASEAN wood products, 1981 report. Volume 1: summary. 2nd ed. J. G. Groome and Associates New Zealand, for Association of South east Asian Nations.

HANSOM, O.P. 1983

Promotion of commercially less accepted species. Paper presented at First UNIDO/FAO Consultation on the Wood and Wood Products Industry, Helsinki, 19-23 September 1983.


Go east young man. Far Eastern Economic Review, 6 October 1983.

KEATING, W.G. 1981

Utilization of mixed species through grouping and standards. Aust. For., 43.

LESLIE, A. 1977

Where contradictory theory-and practice co-exist. Unasylva (FAO), 29 (115): 2-17.


Balancing supply and demand world-wide by the year 2000 through resource management. Paper presented at First UNIDO/FAO Consultation on the Wood and Wood Products Industry, Helsinki' 1923 September 1983.

MARN, H.M. & JONKERS, W. 1982

Logging damage in tropical high forests. In Proceedings of international forestry seminar, 11-15 November 1980. Agriculture University, Serdang, Malaysia.

MEIJER, W. 1970

Regeneration of tropical lowland forests in Sabah, Malaysia, forty years after logging. Malay. Forester, 33.

MILLER, T.B. 1981

Growth and yield of logged-over mixed dipterocarp forest in East Kalimantan. Malay. Forester, 44.

ONG, M.S. & CHEW, L.T. 1983

Utilization of underutilized species. Paper presented at national workshop on utilization of lesser-known timbers, Kuala Lumpur, 1516 August 1983.

PEH, T.B. & KHOO, K.C. 1983

Under-utilized species - present status and research findings. Paper presented at national workshop on utilization of lesser-known timbers, Kuala Lumpur, 15-16 August 1983.

RAO, Y.S. 1982

Forest exploitation in Southeast Asia. In Proceedings of international forestry seminar, 11-75 November 1980. Agriculture University, Serdang, Malaysia


A Faustian dilemma. Unasylva (FAO), 29 (117): 312-14.

SMITS, W. 1983

Dipterocarp mycorrhiza. Paper presented at International Symposium on Future of Tropical Rainforest in Southeast Asia, Forestry Department, Kuala Lumpur, 1-2 September 1983.

TONG, K.H. 1983

A marketing strategy for underutilized timbers in Peninsular Malaysia. Paper presented at national seminar on utilization of lesser-known timbers, Kuala Lumpur, 15-16 August 1983.


Aspects of the marketing of tropical timber: a practical guide. Department of Agriculture Research. Koninklijik Instituut voor de Tropen, Amsterdam. Bulletin 305.

WHITMORE, T. C. 1975

Tropical rainforest of the Far East. Oxford, Clarendon Press.


On pattern and process in forests: the plant community as a working mechanism, ed. by E.I. Newman. Oxford, Blackwell Scientific Publications. Special Publications Services of the British Ecological Society, 1.

YOUNGS, R.L. 1977

Research in tropical wood utilization. Unasylva, (FAO), 29 (117): 9-11.

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