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IV. - Utilization

J.D. BOYD

USUALLY THE COSTS of establishing and tending manmade forests are high. Such forests may be created for purposes other than wood production, including the conservation of soil, water and wildlife, and the provision of recreational amenities. It was evident from the discussions on finance within the symposium, however, that in many cases the availability of necessary funds for the establishment of manmade forests and the viability of the afforestation investment depend almost entirely on the possibilities of selling the building and manufacturing materials and the fuelwood obtained from the forest.

Properly, the subjects of policy, finance, management and silviculture constituted the major portion of the symposium program. Nevertheless discussion in those sessions, as in other international forestry conferences, emphasized that very important utilization factors have often been insufficiently understood or entirely overlooked when man-made forests have been established. Economic utilization is dependent on growing the most suitable type of trees, in forest units of adequate size and in favorable locations. In the process of developing long-term plans for a new forest resource, careful consideration must therefore be given to all factors likely to influence the efficiency of utilization.

Technical and cost factors that are important in sound, long-term planning in forestry include those related to logging, transport (both of raw material and finished product), sawing, seasoning, preservation, manufacturing to product standards, and marketing. In the utilization discussions at the symposium it was obvious that end-product needs differ widely between countries. However, in all cases the economic interdependence of forestry and forest products industries was evident, as was the importance of an overall balance in the development of the two sectors.

It is considered very significant that the cost (per unit volume) of growing plantation wood is usually not more than half and, under certain circumstances, may be as little as a quarter of its total cost, including that of harvesting and transport, delivered to the mill. This, in turn, is usually less than half of the cost of the final product. The factors influencing the costs of harvesting, transport and processing are thus of major importance to the success of an integrated afforestation/ forest industries project, but have been insufficiently appreciated by foresters.

A preliminary draft was prepared for the symposium by E. P. STEPHENS (United States). The final revised chapter was written by J.D. BOYD.

To an increasing degree, economic pressures are making it necessary to obtain greater production from a given forest area. In response, foresters have been apt to plant the fastest growing trees that can be obtained. In many cases relatively little attention has been paid to problems that are likely to develop when the trees are ready for harvesting. Consequently, the costs that are involved for logging, transport, milling, seasoning and product manufacture are sometimes unduly high. In some such cases utilization may not be economic. Poor efficiency in utilization can far outweigh the theoretical benefits of impressive production figures for wood volume in the forest.

Another vital factor, sometimes overlooked, is the desirability of regulating the rate of planting and hence the rate at which the plantations reach maturity. The timing should be decided with a view to full utilization. Thus the volume of timber made available should, as far as possible, be always in accord with practical and economic industry and market development. This will facilitate integration of forest industries to ensure the most efficient and complete utilization of the forest crop.

PREDOMINANCE OF CONIFERS

The future pattern of wood consumption in the coming decades has already been discussed in the chapter on policy. The biggest demand is expected to be for pulp and for sawnwood. Consumption of wood-based panels will also increase very rapidly in proportion to present consumption, but in absolute terms will be less than that of pulp or sawnwood. The general utility of coniferous wood for the two main future usages, pulping and constructional or joinery work, and its characteristics of easy processing and treatment, flexibility and uniformity will continue to make softwood the most favored type of material for forest product industries in many parts of the world. From the conversion point of view, therefore, the conifers are likely to maintain their present predominant position in the world's man-made forests or to assume even greater importance. Of the hardwoods, easily worked timbers of good form, uniform texture and processing characteristics, and suitable for pulping as well as peeling, such as poplars in the temperate zones, are likely to play an increasingly important role. Species of similar properties but adapted to growth in the tropics would be of great value. Gmelina arborea is a promising candidate for this role.

FIGURE 59. - Chemical treatment by aircraft against an insect plague in areas of tourist interest in Palma de Mallorca. (SERVICIO DE PLAGAS FORESTALES, SPAIN)

Effect of site and growth conditions on wood properties and utilization

In his analysis of the influence of growth conditions, Boyd (1967) has referred to a large number of species, and shown that factors which significantly affect the growth of the trees correspondingly influence the quality of the logs, and the characteristics of the wood obtainable from them. Therefore the planning of silvicultural treatments should involve consideration not only of tree form and wood increment rates, but also of the effects the treatments are likely to have on the end use and value of the timber. Most fast-grown wood from man-made forests has characteristics which differ from those of wood of the same species grown in natural forests. Potential uses and value may be significantly affected by these differences.

In some cases, man-made forests have been planted in the hope and expectation that a comparatively high price will continue for timber having special properties, such as the durability and other desirable characteristics traditionally associated with teak, or attractive color and grain effects associated with some woods from natural forests that are used for furniture, veneer or paneling. Yet it is quite conceivable that these desired properties will not develop adequately in timber grown under new site and growth conditions, or in a reasonably economic rotation period for the plantation. As a consequence, the realizable value of the forest produce may not provide an adequate return on the cost of establishment and management.

On the basis of an extensive survey of world literature, Boyd (1967) has shown that the effects of growth conditions on wood qualities and uses of the timber are matters that should be of considerable importance to foresters. In particular, environment factors, including soil type, drainage, density of forest stand, light intensity and moisture availability, all significantly influence form, rate of growth and quality of trees, and also the nature and properties of their wood. Initial planting space, and silvicultural practices, including thinning regimes, pruning, and growth stimulation through fertilization, additionally affect tree form, vigor, log quality and wood properties, and also the development of defects such as spiral grain and compression wood. Critical deficiencies in mineral and humus content of the soil may also have important effects on growth and properties. Lack of growth -vigor can render trees highly susceptible to attack by destructive pathogens and insects; this may seriously reduce the quality and value of the wood.

For many species the age of the trees at the time of felling can have a considerable effect on wood properties. Hence consideration should be given, during planning and management of man-made forests, to the effect of rotation periods on conversion techniques, as these have an effect on economic recovery, and influence the quality of timber obtainable.

Elliot (1967) has pointed out that, to facilitate more extensive and efficient utilization of man-made forests of eucalypts, there is an outstanding need, in each country in which they are grown, for detailed knowledge of the properties of every species planted there. This applies particularly to information on the wood properties of young trees, which form the bulk of the world's man-made eucalypt forests. Some indication of the mechanical properties can be obtained by adjusting known values for the same species grown elsewhere, in accordance with the ratios of the densities of the timber from both areas (Boyd, 1967). The higher density eucalypts generally are not suitable for pulping.

The discussion emphasized that data on the properties of wood of all species grown in plantations, and also of the same species growing in natural forests, would be of great value if they were collated and distributed widely. Knowledge of wood properties facilitates the choice of the most efficient conversion techniques, while conversely developments in conversion techniques can modify the effects of intrinsic wood properties. In addition, assistance was sought to define simple techniques for assessing the important properties of plantation-grown timbers.

Hughes (1967) has discussed the utilization of the wood of low altitude tropical pines, in the zone from sea level at about 23° latitude north or south to between sea level and 1,200 to 1,500 meters (4,000 to 5,000 feet) at the Equator. Even with good management the commercial timber yield from most natural tropical forests is low. Difficulties arise in harvesting and converting a large range of sizes, and in marketing many species of varying utility and quality. These problems of natural forests will become more acute with the general trend toward the increasing use of wood products involving chipping and pulping. For these processes uniformity in size of tree and in quality of wood is desirable.

It is difficult to be precise in forecasting changes in demand for various timber products or the effects of rapid developments in the technology of conversion. For this reason Hughes advocates growing species that will produce a high yield of wood suitable for a range of important end uses. Softwoods are more likely to be suited to this basic aim than hardwoods, and are often more adaptable to poor and infertile soils.

Considerable success has been achieved in making large plantings of coniferous species at high altitudes in the tropics. In this zone, however, there is little chance of acquiring a significant amount of additional land suitable for growing conifers. There is thus an incentive to determine which conifers will grow satisfactorily at lower levels, where often large areas of land are more readily available. It is an added incentive that more favorable sites for forest industries may be found at the lower altitudes, especially when good water supplies and facilities for effluent disposal are necessary, as in a pulping operation.

There are few data on the wood properties of tropical pines. Work on Pinus caribaea has recently been summarized (Hughes, 1967; Chittenden et al., 1967). This species has the disadvantage of a very wide density range when grown on different sites, while a serious reduction in the grade of sawn timber is frequently caused by spiral grain, compression wood and high resin content. On the other hand, pulping tests of wood from young plantations in several countries have shown promise of satisfactory yield and strength properties; but it should be noted that testing was of small samples, was done on a laboratory scale, and gave very variable results. Little information is available on P. merkusii, P. oocarpa and the lesser known tropical pines.

FIGURE 60. - Release of insect parasite in biological control trials in Spain. (SERVICIO DE PLAGAS FORESTALES, SPAIN)

Araucarias may also be suited to these areas and should be tried, though there is a need for caution, as sometimes the cost of their establishment in subtropical and tropical areas is excessively high. Experience in Australia indicates that, although juvenile wood and compression wood may cause problems in the utilization of plantation-grown araucarias, these are being overcome.

Boyd (1967) refers to extensive experiments made by forest research workers in Australia, the United States and elsewhere on the practicability of improving the potential value of planting stock for man-made forests. The procedure involves selection of parent trees having desirable characteristics, followed by the application of various biological controls on the development of progeny, with a view to obtaining optimum tree and wood qualities. Careful assessments have shown that considerable benefits may be obtained. Tree improvement studies should be undertaken at the earliest possible date in all areas where new forests may be grown, so that the maximum advantage may be derived from man-made forests throughout the world. A useful guideline for the development of such a research program is contained in the description of the results of wood quality research carried out on Pinus patula and P. khasya from 1965 to 1967 by the Forest Genetics Research Laboratory of the Agricultural Research Council of Central Africa (Burley, 1967). It is likely that the wide variability and serious defects of the low altitude tropical pines can be substantially reduced by careful selection of seed source, use of tree improvement procedures, and silvicultural treatments (Hughes, 1967). The importance of the early and careful assessment of wood properties in addition to characteristics of growth and form during the conduct of species and provenance trials needs to be stressed. The efficient conduct of such trials will be enhanced if plans now being drawn up by the Commonwealth Forestry Institute, to codify and publish the procedures for testing species and provenances and for sampling trial plots to examine wood quality at an early age, come to fruition.

FIGURE 61. - Inside view of a district fire truck in South Australia showing the equipment layout (WOODS AND FORESTS DEPARTMENT, SOUTH AUSTRALIA)

Techniques in felling, logging and transport

Because a considerable proportion of the cost of timber received at the mill is incurred in logging and transport, minimization of the costs of these operations can be of real value to the ultimate consumer, and should assist in keeping wood products competitive in price. However, Hanson (1967) states that action to minimize these costs could conflict with a policy of producing the maximum volume of wood of usable quality from a given area. Further, the cheapest method of extraction from the forest may not necessarily be the best if it adds considerably to processing costs.

It is clear that techniques in felling, logging and transport that are appropriate to a developing country are not necessarily the same as those suited to countries where the forest industry is large and has been long established. As a general philosophy in respect to logging and timber transport methods in Australia, if alternative methods lead. to approximately the same present overall cost, the one with the least labor cost should be adopted. This will be advantageous over a period, because labor costs are increasing at a faster rate than machine costs. Also as a result of this choice, if logging production has to be increased for a short period, this can be achieved with least cost and least increase in working hours. Correspondingly, if production has to be decreased, there will be less social disorganization. Difficulties in attracting labor to forest work also favor this preference.

For a less developed country it is sometimes desirable to employ the largest practicable labor force. Labor costs tend to be low, machinery costs relatively high, and capital for substantial expenditure difficult to obtain. Frequently also, sufficient skilled labor and technical facilities are not available to operate complex machinery and maintain it efficiently. In some cases these disabilities may be partially overcome by pooling machinery and skilled personnel belonging to adjacent areas, and by operating these on a cooperative basis.

Logging in conjunction with clear-felling involves no restraints on the choice of the most suitable types of equipment, except those determined by terrain, size of logs, extent of annual logging task, and the size and ability of the available labor force. In fiat country the most common method is to fell with chain saws, and then delimb and cut into log lengths at the stump. Even for logs of substantial size, extraction and loading can be done by the truces used for transport, providing these are fitted with a power winch and hauling wire, and a crane. Such a system generally leads to minimum cost and flexible operation, and may be particularly suited to developing countries when the volume being handled is not very large. Where terrain and soil conditions do not permit ready access to the felling area by road vehicles, crawler or rubber-tired tractors or wire rope systems may be used to haul logs to the roadside. Generally crawler tractors are slower and more costly to operate than rubber-tired tractors capable of doing the same work. When ground skidders are used in small operations, it is usually better to combine the skidding and loading functions in one machine rather than combine the loading and carting functions as is more commonly practiced. The main reason for this is that the efficiency of the skidder is not materially decreased by the addition of loading equipment, but the efficiency of the truck is significantly reduced. Furthermore, except on short hauls the one skidder will normally service several trucks, so the capital invested in loading equipment is less if it is attached to the skidder. On large operations the functions of skidding and loading should be assigned to specialist machines.

In thinning operations access is limited, and damage to the remaining trees must be avoided. It is common to fell access rows and to thin stands between them. Chain saws and trimming axes are used. Where the terrain permits, logs in short lengths may be loaded by hand or by using a light crane on the truck. Where immediate access by road vehicle is not practicable, light tractors or horses may be used for log haulage. However, for substantial log volumes, operation with horses tends to become uneconomic. When the volume of each log exceeds 0.2 to 0.3 cubic meter (7 to 10 cubic feet) and a large total volume is being handled, special skidders may be most advantageous. On slopes steeper than about 20 degrees, if it is necessary to work uphill, normally some form of skyline wire rope system is necessary.

Generally it has been found most economic to site the forest and the mill or factory close enough to each other to make it practicable to use only road transport. Time saved due to close proximity of forest and industry also tends to minimize degrade of timber between felling and conversion. If substantial exporting is intended, it is essential to seek a location near or with good access to a port. When a favorable industry site necessarily involves very long hauls, rail transport may be most economical. If the wood is for pulping, it is not uncommon to convert and transport it as chips over long distances, even by ocean-going bulk carriers. For large volumes and semipermanent supplies, transport of chips by pipeline may develop. To achieve overall economic harvesting, transport and processing, the forest should be concentrated in large units, irrespective of the distance between forest and industry site, and the forest road system should be carefully planned before large-scale planting begins. There has been a worldwide trend toward hauling in longer lengths on conventional trucks and pole semitrailers.

Hanson (1967) concludes that, because of the relatively high cost of logging operations, substantial advantages can result from research directed to reducing contributory costs, and also accident hazards. He advocates the development of more efficient methods and machines, and specialized training for managers and workmen. Subjects suggested for investigation include new equipment and methods as referred to in the recommendations. More detailed work studies, of the kind described by Curro and Ghisi (19673 for poplars, are essential for the proper evaluation of the relative importance of felling, trimming, sorting, crosscutting, loading and related operations in overall logging costs. The Joint Committee on Forest Working Techniques and Training of Forest Workers is the most appropriate body to follow up the recommendations.

Mechanical harvesters, which combine several functions now handled by separate pieces of machinery, are being developed in North America and Scandinavia, but their reliability is not proved. Some use conventional mechanisms for cutting into tree lengths and others use hydraulically operated shears. Since considerable quantities of wood will continue to come from small farm woodlots, there is a need for a small mobile harvester.

FIGURE 62. - Loading methods and machinery. Douglas fir thinnings being loaded for transport to Waipa sawmill in Kaingaroa forest, New Zealand . (NEW ZEALAND FOREST SERVICE-JOHNS)

FIGURE 63. - Early returns from fast-growing plantations. Measuring logs for commercial thinning in teak aged 10 years at Mount Lawes, Papua. (DEPARTMENT OF INFORMATION, PAPUA AND NEW GUINEA)

FIGURE 64. - Sawn timber produced from the same thinnings as in Figure 63.

Processing techniques

Experience and research have led to the development of satisfactory techniques for the conversion (sawing and processing solid form) and effective utilization of eucalypt and other widely used species from native forests (Boyd, 1967). The growth rates usually have been relatively slow, and the harvesting age high, but the reactions of the timbers during conversion made it necessary to develop special techniques. However, there is ample evidence that, while existing knowledge is helpful, plantation timbers of the same species present new and sometimes very different problems which must be solved to achieve efficient conversion to good quality products.

There are several causes of the problems which arise during the conversion and utilization of fast-grown plantation softwoods and eucalypti. With some softwood species a large proportion of the cross-section of the tree contains juvenile wood, and in addition possibly significant quantities of compression wood and severe spiral grain. The juvenile wood is of relatively low strength, as also is sawn timber with severe spiral grain. Each of the three defects tends to cause troublesome distortion in a proportion of the sawn timber during seasoning. Further, they make it somewhat unstable with subsequent seasonal moisture changes in use. However, appropriate sawing and seasoning techniques can reduce the severity of the distortion effect. In fast-grown eucalypts growth stresses may cause splitting and distortion of logs and sawn timber, and give rise to serious difficulties in conversion and use (Boyd, 1967; Elliot, 1967). Again, the effects can be minimized by the application of appropriate techniques before and during sawing and seasoning. Excessive gum veins and grub holes occur in some areas in Australian plantations and may be associated with site (Elliot, 1967; Bootle, 1967).

Some generally applicable techniques of sawing, seasoning and grading of timber from man-made forests have now been well established. However, knowledge of these is not sufficiently widespread. Certainly the extent of the application to the full range of plantation growth conditions and manufacturing and use problems in new forests throughout the world is quite inadequate. During the discussion, the desirability of documenting and circulating information on techniques known to be suitable for sawing and seasoning of plantation-grown eucalypts and softwood was emphasized.

While the wider application of present knowledge can be very helpful, considerably more knowledge is desirable to facilitate efficient utilization. Countries growing man-made forests are likely to find it advantageous to undertake some research into methods of conversion) and product development, to ensure the most beneficial economic use of their forest crops. This need, and the practicability and cost of meeting it, should be considered before species are chosen and planting of new manmade forests initiated. Involved in this is an assessment of research facilities available in the area to solve the problems that will arise with maturity of the crop.

Plumptre (1967) reports on a general problem which is important, though it may appear on first thought to be only local and also simple in comparison with some of those mentioned above. Initially, the sawmilling trade in Uganda could not be interested in logging on the steep slopes involved, or in sawing small quantities of thinnings available from the relatively scattered and small plantations. To help overcome this difficulty in utilization, the forest service purchased a portable sawmill, and trained operators. As experience was gained, equipment and techniques were improved, and there was a corresponding increase in recovery of sawnwood. It was considered that the increased volume of timber that would become available with maturity of the forests would ultimately justify fixed mills. By that time the training and experience obtained in logging, and in sawing the thinnings with the portable equipment, should lead to efficient operations. On the other hand, a considerable handicap to economic conversion in Uganda has been caused by the small, widely dispersed forest units, as well as the relative inefficiencies in conversion.

Developments in utilization of wood from man-made forests

In the early stages, exploitation of a man-made forest may involve only the provision of firewood or charcoal. Later the trees are likely to be used to supply raw material for a range of products such as building timber, furniture, joinery, plywood, hardboard, particle board, and pulp and paper. The use of timber from extensive plantings of poplars in Italy, that were grown in the first instance to form windbreaks, is an example of the growth of utilization and diversification into a wide range of products. Giordano (1967) states that these trees now satisfy half of Italy's total industrial wood requirements. They support large industries which provide sawn timber, supply most requirements in plywood, all the demand for wooden matches, and the raw materials for substantial production in fibreboard, particle board, wood-wool slabs, secondary industries and crafts, and groundwood and semichemical pulp.

Huddleston and Bootle (1967) have traced the stages in the development of the market for plantation-grown Pinus radiata in New South Wales, starting with casewood and proceeding to a wider range of building and manufacturing products. Apparent defects during the early stages were largely overcome by the adoption of proper seasoning, impregnation and grading practices, and the avoidance for most purposes of juvenile wood and wood with sloping grain, both of which gave rise to excessive distortion. Machine stress grading has been introduced and its use is expected to increase.

Elliot (1967) has reviewed development in the utilization of eucalypts in Asia, Australasia, Africa, Latin America, the Mediterranean region and the Near East. The age at which these trees are harvested from manmade forests varies between countries from as low as about 6 years to as high as 30 years. Short rotation harvesting, which is generally associated with coppicing, has become a very significant factor in the economics of utilization of eucalypts from plantations. Much of this timber is being used in pulping for paper, hardboard, or rayon manufacture. Also, large volumes are being used for industrial charcoal in South America, or for mining timber in South Africa. A considerable amount in the young to medium age group is being used in round form for posts, poles and building timber. A smaller proportion, mainly from the longer rotation crops, is being used for sawn timber. Eucalyptus oil is also produced. Optimum age for harvesting depends on growth conditions, species and the end products desired.

In early attempts at utilization many countries have encountered difficulties due to unfamiliarity with the characteristics of eucalypt timbers and suitable conversion techniques. South Africa has overcome many of its problems through research, and extensive and varied utilization is now being achieved. In Argentina also, utilization now extends over a wide range of products: these include sawn timber used in construction, furniture, parquetry, fencing material and fruit cases, round timber for posts, poles (which are given preservative treatment) and pit props, and for the production of veneer, and also pulp and fibreboards. In Portugal the extensive eucalyptus plantations, which cover 180,000 hectares, provide a wide variety of products (Goes and Ferreirinha, 1967). For a long time the wood was used chiefly for firewood, but this form of utilization has declined greatly in recent years. Eucalypts are also used for sleepers, cooperage, furniture, peeling, constructional and flooring timber, as roundwood and for production of essential oils. Easily the most important product, however, is pulp, for which over 1 million cubic meters of eucalyptus are consumed each year, mainly from trees 8 to 12 years old. In most other countries fewer products are produced at the present time, however, partly because plantations are young, and partly because suitable technologies and markets have not been developed. Production of pulp for paper, rayon and board products appears to have considerable potential.

FIGURE 65.- Effect of site conditions and growth rate on wood properties. Cross section showing typical growth pattern of Pinus caribaea var. hondurensis from a natural stand in British Honduras where recurrent and severe water stress causes frequent alternation between formation of earlywood and latewood, with a high proportion of latewood. (HUGHES)

FIGURE 66. - Effect of site conditions and growth rate on wood properties. A typical growth pattern, of plantation-grown Pinus caribaea var. hondurensis, grown in Fiji, where there are soils allowing deep rooting and growth that is almost continuous all year round. This gives wide rings with a high proportion of earlywood. (HUGHES)

Development of integration in utilization

Integration implies the production of a number of different end products from a basic raw material. These end products may include saw timber, plywood, particle board, etc., as well as pulp and paper products. Integration should also co-ordinate the management of the forest with that of the harvesting, conversion and marketing services, in a common overall plan, to generate the greatest wealth for the industry and the country. Fuller information on the types of integration and factors which affect it may be found in the report of the symposium on integration in the forest industries (Timber Committee, Economic Commission for Europe, Geneva, February 1967).

The basic objective in integration is to secure better utilization of raw materials and residues, better results from capital investment and labor, savings in fuel and power, and diversification of production as an economic safeguard. This should lead to the most economic exploitation of the forests. It involves marketing a range of products yielding the highest investment returns. It is in line with current trends in other industries, where big industrial complexes are based upon closely integrated utilization of raw materials coupled with highly efficient systems of distribution and marketing.

The practicability of integrated use depends on availability of timber in a suitable range of wood types and qualities, each in sufficient volume and at convenient locations to allow establishment of efficient industries to produce each important product. In this concept, generally small,- widely dispersed forest units tend to impose severe handicaps on integration and overall economic utilization.

The location of a forest and the location of the industries based on it are interdependent. In the past, most attention has been paid to land availability and biological factors which affect the siting of the forest, while the technical, economic and social factors which affect the siting of the forest industry have all too often been overlooked.

Information of many kinds is needed: on forest resources, on land tenure, on wood cost, on other prerequisites such as power, water, fuel, chemicals, etc., on transportation, labor, markets, and on investment requirements, financing and other related factors. The factors which determine stability of the labor force, e.g. acceptable living and social conditions, should not be neglected. The forest should be located to suit the most site-sensitive of the industries chosen for integration; this is usually the pulp mill. Clearly, success in integration is more probable if foresters understand the influences of the foregoing factors, and make appropriate allowance for them in long-range planning, before planting the forests.

The most effective industry integration may involve production of sawn timber in various forms, also plywood, particle board, hardboard, pulp, paper and paperboard. In addition, it will include the use of round timbers such as posts, poles and piles. Because the capital requirement for this complete program is large usually it will be most practicable to develop new industry units successively, as financial resources in the complex are strengthened, and as the forests approach maturity. An early stage in integration may therefore take the form of producing a number of different sawn products, and utilizing round timbers as much as possible. Mackney (1967) illustrates another situation in New Zealand, where the initial conversion was in a very small sawmill, followed a little later by manufacture of fibreboard and later again by a major pulping industry. Meanwhile, some sawing of case timber was undertaken and also the manufacture of plywood.

When integration is achieved within one company, the greater diversification of production generally leads to increased stability of the complete industry group. The balance between the various sectors of the integrated complex is unlikely to remain constant, since market trends, technological developments and the level of competition from substitute materials will differ in each sector. A flexible raw material, which can be transferred from the less to the more profitable end product, adequate scale of working and integration in depth offer the best combination to overcome periodic fluctuations in demand (Mackney, 1967). The development of an integrated industry complex in the most economic way depends on the nature of decisions of long-term significance. These include decisions on locations of forests and industry units, the size of each and the timing of forest plantings and of the establishment of the various industry operations.

FIGURE 67. - Poplar logs ready to be used for making matches and packing cases, at Astalif, Afghanistan. (NEW ZEALAND FOREST SERVICE-WILSON)

Generally the marketing of roundwood is not of major importance in fully integrated utilization, but in the interim period before forest yields reach a sufficient volume to warrant major industry development it can provide a means of disposal of the wood harvested, particularly thinnings. The same may be said of the sale of chips. On the other hand, because sawn timber is normally a product of high value, its continued supply has a place in an integrated industry. To obtain the best timber for sawing, attention must be given to planting the correct types of trees, and to giving these appropriate silvicultural treatments. Plywood also is of high value, and its production can be particularly rewarding when it is practicable to use lathe cores and waste veneers to produce pulp.

Mackney refers to capital requirements, the significance of industries and the qualities of timber acceptable for the manufacture of various products. The production of particle board or fibreboard requires a much larger capital investment than the production of sawn timber. The minimum quality of wood required for fibreboard is somewhat less than is necessary for particle board. However, the manufacture of either product has the important attribute of facilitating economic use of relatively low-grade timber such as thinnings, and low value material such as sawmill offcuts, waste from veneer mills, and possibly some sawdust. To a limited extent, the manufacture of -pulp and paper provides an alternative outlet for the utilization of the low grade materials. The pulp and paper mill is likely to form the major economic unit in the fully integrated industry group. To provide a range of high-quality paper products, including strong packaging material and writing papers, it is necessary to have suitable supplies of both softwood and hardwood timbers.

FIGURE 68. - Access tracks and loading areas for large-scale mechanized thinning in Kaingaroa forest, New Zealand. (NEW ZEALAND FOREST SERVICE-WILSON)

The establishment of industry units based on natural forest frequently precedes the planting of man-made forests. They may be justified even in those types of natural forest, such as the tropical high forest, in which the variety of species and wood properties and the need for selective harvesting handicap economic exploitation. Financial strength built up through these units can then be used to replace the natural forest resource with a man-made one, which should have a higher realizable value. In planning and developing any new forest it should be ensured that the minimum economic supply of timber necessary to satisfy each new processing unit in the industry complex is available at the optimum time for establishment of that unit. To obtain the best return from the large investment involved in plantation forestry, it is necessary to start some industry at the earliest possible time, and this may involve the rapid establishment of large areas of plantations in the early years, and the acceptance of an abnormal age class distribution during the first rotation.

Where the large capital required for its establishment is not a major problem, a pulp mill presents the first major opportunity in economic utilization of the wood from a manmade forest. This is because young trees are acceptable for pulping before they are suitable for sawing. Normally, however, an economic pulp mill cannot rely entirely on thinnings for its wood supply. For most of its needs clear-felling is necessary. Correspondingly and to facilitate later integration of industry, the forest should be established fast enough to enable the major demand of the pulp mill to be met while felling only part of each forest age group, and a percentage of the trees should be left to a more advanced age to enable production of good-quality veneer and sawlogs.

Because product costs must be kept low to be competitive and the total cost of harvesting, transport and manufacture is very much higher than that of growing the timber, forests should be planned to suit industrial requirements. The alternative of planning to exploit forests that have been established without full consideration of these needs, though it has been normal; practice in the past and has produced, fortuitously, such outstanding successes as the Pinus radiata forests of New Zealand and the poplar row plantations of Italy, is not likely to lead to optimum development of the product market, or to ensure maximum utilization of the forest produce. In this case, the return on the forest investment would not be as high as it could be, and it may not be adequate.

Mackney (1967) feels that forests should be managed in such a way as to develop as many good qualities in the timber as is possible without incurring heavy additional cost. Beyond this, he suggests that it may be better to adapt technology in the mill to upgrade the products to the required quality, rather than endeavor to build quality factors into the raw material. In discussion, however, it was emphasized that as expenditure incurred in growing the trees is a small proportion of total cost, in some circumstances substantial additional effort to improve the quality of the forest may cost considerably less than the alternative of trying to improve the raw material after harvesting the tree. Any such modifications during manufacture may be costly, and may be required for an indefinite period and possibly for a range of products. Also, there may be practical as well as economic limits to what can be done to the material after harvesting, in attempting to lift product quality to the level necessary to gain market acceptance.

Extensive softwood plantations in New Zealand, Australia and South Africa have led to the establishment of advanced forest industry integration in these countries. It does not appear that the equivalent has yet been achieved in the utilization of hardwood plantations, with the exception of poplar in northern Italy and of eucalyptus in South Africa.

FIGURE 69. - Waipa sawmill, New Zealand. (NEW ZEALAND FOREST SERVICE-WILSON)

In developing countries careful consideration should be given to the selective establishment of manufacturing units in accordance with capital availability. This industry growth need not follow the same sequence, or even be of quite the same nature, as in a more advanced country. Relatively small capital is needed for the building of sawmills, joinery and furniture shops, prefabrication of building components for housing, briquettes from charcoal, or chipping plants to supply pulp mills. In some cases, the building of particle board factories may be practicable providing there is an adequate market. Governments in the developing countries can materially help the wood industry by specifying the use of timber in their housing projects, schools and public buildings. Similarly, :round timbers treated with preservatives can be specified for posts, poles, piles and bridge building.

Where, for market or other reasons, manufacture in individual countries cannot in itself be an economic proposition, production on a regional basis clearly offers attractive opportunities. This allows the benefit of some measure of supply sufficiency without imposing severe economic penalties. Simultaneously it may lead to more efficient utilization of the forest resource.

Another significant proposal during the discussion was that the integration of timber and food production should be attempted. Current and anticipated major food shortages throughout the world pro-vice an incentive for the study of the relevant economics. Examples of possibilities were given; it was stated that the U.S.S.R. annually produces 500,000 tons of fodder yeasts from timber, while in Spain much pig farming is based on the use of acorns from the species Quercus ilex.

Other possible combinations of timber growing and food production include walnuts, cashew nuts, chestnuts, hazelnuts, carobs and figs.

Conclusions

The cost per unit volume of growing timber to the age of harvesting is usually not more than half and, under certain circumstances, may be as little as a quarter of the total cost delivered to the mill. Further, the cost of the timber at the mill is usually less than half of the total cost of the final product. Therefore, the allocation of a substantial proportion of forestry expenditure to research, to produce the most suitable type of timber in the forest, may be more than justified, if it leads to reduced costs in harvesting and processing the material, and to more competitive marketing of the products. Another very important factor which affects the economics of utilization is the correct siting of the forest and the correct phasing of planting operations, so as to promote the optimum development of the forest industry sector.

The relatively high cost of harvesting indicates that research on felling, logging and some preliminary processing of the timber on the forest site may lead to significant savings. In the more developed countries, an increasing difficulty in recruiting labor for forest operations emphasizes the need for additional and improved mechanization. On the other hand, in developing countries labor is more freely available, and resources for the purchase and maintenance of mechanical equipment are limited. This suggests that attention should be given to the production of new, simple, yet efficient tools and equipment, and the determination of techniques suited to the exploitation of the forest resources in those countries.

Studies have shown that, in the growth of forests, environment and silvicultural practices have a substantial effect on wood properties and timber qualities. The considerable effect of these on the ultimate utility and value of the timber should be appreciated by forestry planners, before they establish new man-made forests. Other analyses have demonstrated that tree improvement research can. increase both the volume and quality of wood produced from a given site; such research should be given high priority, because of increasing demands on land for food production and other purposes. While qualities of wood from short-rotation plantation species have sometimes caused difficulties in conversion,- success achieved in some countries indicates that practicable solutions can usually be found.

The planting of forests and the development of forest industries have too often been planned in mutual isolation. Only the most careful integration of the two sectors can ensure that man-made forests will make their full potential contribution to national and international progress.

References

*BOOTLE, K.R. 1967 Some problems in the utilisation of plantation eucalypts in New South Wales. Canberra.

*BOYD, J.D. 1967 Effect of plantation conditions on wood properties and utilisation. Canberra.

*BURLEY, J. 1967 Pine wood studies in central Africa: I. Introduction. Objectives and materials. Canberra.

CHITTENDEN, A.E., JARMAN, G.C., PALMER, E.R. & HUGHES, 1967 J.F. The pulping properties of Pinus caribaea. Commonw. For. Rev., 46(1): 22-35.

*CURRO, P. & GHISI, G. 1967 Chain-saw utilisation times of a poplar plantation. Canberra.

*ELLIOT C.S. 1967 Utilisation of eucalyptus wood. Canberra.

*GOES, F. & FERREIRINHA., N.P. 1967 La culture et l'utilisation des eucalyptus au Portugal. Canberra.

*GIORDANO, G. 1967 Aspects de l'intégration des plantations de peupliers avec les industries utilisatrices de bois en Italie. Canberra.

*HANSON, A.G. 1967 Logging and transport methods in man-made forests. Canberra.

*HUDDLESTON, E.B. & BOOTLE, K.R. 1967 Exotic pine utilisation in New South Wales. Canberra.

*HUGHES, J.F. 1967 Utilisation of the wood of low altitude tropical pines. Canberra.

*MACKNEY, A.W. 1967 Possibilities of man-made forests for the integration of forest industries. Canberra.

*PLUMPTRE, R.A. 1967 The utilisation of conifer thinnings from small plantations in Uganda. Canberra.

NOTE: *Paper submitted to World Symposium on Man-made Forests and Their Industrial Importance, Canberra, April 1967.


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