A World Bank Policy Paper
The Forest Sector

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Appendix B.
Technical Notes

Examples of Sustained Management of Tropical Timber

Management of forests and forestland is both an art and a science. Although most parts of the world have long traditions of forestry— many of them derived from American and European professional and scientific experience—there remain significant areas of uncertainty and research needs. This appendix briefly summarizes the state of knowl-edge on a number of key technical issues in forest management.

Tropical forests are highly complex systems that have not proved easily amenable to management. A few countries have embarked on promising approaches to timber management. Foremost among them is Malaysia, which in 1910 started a series of silvicultural treatments known as departmental improvement fellings. This was later modified into a system of regeneration improvement fellings. Then, on the basis of observations of the heavy fellings during World War II, the Malaysian forestry department developed the Malaysian Uniform System (MUS), which was used until the late 1960s. Since 1970 peninsular Malaysia's forests have been managed on the Selective Management System (SMS). Although the SMS has not yet been in operation for three harvests (because felling takes place only every twenty-five to thirty years), measurements of upper-canopy trees suggest that sustainable manage-ment has good prospects for success.

The Myanmar teak forests have been managed under a sustainable system since the 1 840s. The accumulated annual increment was removed on thirty-year felling cycles using nondamaging extraction methods (elephants and water transport). The abundance of teak in these forests made them easier to manage sustainably than the more heterogeneous tropical rain forests. It is not clear to what extent sustainable manage-ment is being practiced today.

A number of management systems have been tried in different coun-tries. These include the monocyclic, shelterwood. and polycyclic sys-tems. Monocyclic systems such as the MUS provide for the removal of all merchantable trees down to a specific diameter at breast height in a single operation, followed by a poison-girdling of the remaining large noncommercial stems. Silvicultural treatments are continued at inter-vals to promote the growth of desirable species, and a second crop reaches maturity after seventy years. This had some promise in Malaysia's lowland dipterocarp forests, but because most of these forests were converted to oil palm and rubber plantations, the system was discontinued in the 1960s. The MUS was unsuitable for mountain dipterocarp forests and was replaced by the Selective Management System. The SMS is generally used in Africa, more intensively (up to two trees per hectare every twenty years) in accessible areas such as West Africa and less intensively (one tree per 2 hectares every forty years) in remote areas such as the Zaire basin.

Tropical shelterwood systems (TSSs), in which the canopy is opened several years before harvest to provide adequate regeneration, were tried in Nigeria and Ghana in the 1940s and 1950s. These systems were unsuccessful because of low regeneration rates for the prime economic species, vine infestation, and the high labor costs associated with the numerous intensive interventions. A recent development of this system is being practiced with rather more success in Peruvian Amazonia (Palacazu Valley), where it is known as the "strip shelterbelt system."

Polycyclic systems, such as the modified selection system of West Africa and the SMS of Malaysia, are designed to ensure the regeneration of commercial species that will become the final timber crop after twenty to thirty years. These systems are showing more promise. They rely on efficient monitoring of stand development, with thinning, where neces-sary, to favor the growth of promising individual timber trees. Although these systems are considered moderately successful in Malaysia, the available evidence does not suggest that current systems are working satisfactorily elsewhere—apparently because of the way in which they are being implemented rather than because of the systems themselves.

Management based on polycyclic systems is being carried out on an operational scale in Australia (Queensland), Ghana, India (including the Andaman Islands), Indonesia, Malaysia, Myanmar, Nigeria, the Philip-pines, Trinidad, and Uganda. In other countries there are examples of management on a pilot demonstration or research scale. The better known examples are in Brazil (Ibama, Cpatu, and Tapajos), western Cameroon, Central African Republic, Colombia (Cali), Cote d'Ivoire, French Guiana, Mexico (Quintana Roo), Papua New Guinea, Peru (Pal-acazu and A. von Humboldt), Venezuela (Ticoporo and Barinas), and Zaire, Possibly one of the best examples of a potentially successful polycyclic system of sustained yield management is in Trinidad; the system was introduced in 1927, and according to recent observations the forests look better today than they did thirty years ago.

There are four main reasons why most management systems have failed. First, inability to limit damage to the ecosystem leads to inade-quate regeneration. This occurs because of the desire to maximize initial offtake to offset the very large capital investments often required and because forestry department operating rules are often ignored. Second, the international market has generally dictated concentration on only a few species whose regeneration may be difficult or expensive (and that are less economic to market than a variety of species). Third, controls over productive forest have rarely been rigorous. Logging lease agree-ments have discouraged investment in future stands, and harvested areas are too often encroached on by rural populations or used as a source of poles or fuelwood or for illegal timber felling. Only where controls are rigorously enforced can a harvesting system hope to be sustainable. Finally, incentive policies favor exploitation of forests for short-term benefits and profit maximization.

Since the 1960s the approach adopted by most donor agencies con-cerned with forestry has been (a) to establish monocultures of industrial plantations, usually of exotic tree species, to meet industrial wood needs and (b) to support social forestry, farm forestry, and agroforestry initia-tives. Little effort has been directed toward the natural forests of the tropics because their ecological complexity makes them difficult to manage. Thus, for some thirty years scant emphasis has been placed on further development of management systems.

Plantation Establishment

Plantations make up about 100 million hectares of temperate plantations and about 35 million hectares of tropical and subtropical plantations. As measured by wood increment per unit area, well-managed plantations are many times more productive than most natural forest systems, and the plantation forests of many countries (for example, Australia, Chile, Kenya, New Zealand, and South Africa) are now an important component of their productive forest resources. Managed natural forests in the tropics can be expected to yield between 2 cubic meters and 8 cubic meters per hectare annually, whereas man-made plantations in the tropics can yield between 10 cubic meters and 60 cubic meters per hectare annually depending on site, species, and intensity of management. The financial returns from plantation forests can compare favorably with those from alternative land uses.

Compensatory and tropical hardwood plantations

Expectations that the expansion of softwood or eucalyptus plantations would substantially reduce the pressure on tropical moist forests have generally not been fulfilled. These plantations usually produce quite different products (industrial sawnwood and pulpwood), and thus the opportunities for substituting plantation-grown material for high-qual-ity hardwood from natural forests are few. In semiarid and arid regions, providing plantations for fuelwood and building poles can reduce pres-sure on natural woodland, but it is in these regions that the greatest number of failures has occurred, primarily for social reasons and be-cause of lack of technical expertise. Temperate forests, which formerly yielded sawlogs for the local market, have been replaced by plantations in some countries (for example, in Chile, New Zealand, and South Africa and in the highlands of Kenya).

Tropical hardwood plantations can reduce pressure on tropical moist forests. Unfortunately, with a few notable exceptions (such as teak), valuable tropical hardwood species are difficult to grow in plantations. The reasons lie in the ecology of the trees: most species have evolved in highly competitive, polyspecific environments, and many are elements of late successional stages. Such species are usually ecologically unsuited to being grown in pure stands or, when young, in open environments. Attempts to do so usually result in chlorosis and decline or in fatal insect attacks. This supports the notion that production from natural forests should concentrate on valuable decorative, joinery, and veneer species rather than on species for industrial cellulose, poles, and the like, which can probably be grown more effectively in plantations. There is, how-ever, merit in undertaking more research on a limited number of valu-able tropical hardwood species that appear to have some prospect of success under plantation conditions, such as Cordia alliodora, Shorea spp. and Eucalyptus spp. (for example, E. pilularis). Very large areas of well-managed hardwood plantations are common in temperate countries of Western Europe and the northeastern United States. Some European countries have made deliberate policy decisions in recent years to con-centrate on the production of high-quality, decorative native hardwoods on suitable sites, in anticipation of a continual decline in and eventual cessation of supplies from the tropics.

Current research suggests that plantation forest systems can be man-aged to meet criteria of sustainability, and experience with particular species and ecosystems suggests that objectives other than production, notably conservation, can be satisfied if improved land use planning precedes plantation design and management.

Plantation forestry has become synonymous with large-scale, monocultural intensive tree growing for the production of industrial wood (poles, fuelwood, pulpwood, sawnwood, and so on) This model is typified by the coniferous plantations in both the Southern and Northern hemispheres and by temperate and tropical eucalyptus plantations. Optimal management strategies for such plantations are, in general, well developed and sophisticated. Historically, most development agencies have promoted this form of plantation forestry. With hindsight, it is apparent that the traditional model of plantation forestry is most appro-priate in industrial countries where land resources are not scarce. An alternative approach is required for many developing countries. Given the circumstances of rural societies and the land scarcity prevalent in much of the non-industrial world, the integration of other crops with plantation forestry is likely to be the best means of successful plantation production in the future.

The primary distinguishing feature of trees as wood production crops is their relatively long production period, which is seldom less than four years, commonly ten or more years, traditionally at least twenty-five years in the tropics, and usually at least twice that in temperate regions. The return on investment for well-managed, fast-growing tree crops is usually of the order of 10 to 15 percent and probably about 5 percent for slower-growing temperate or tropical species. In many countries the successful involvement of the private sector in plantation forestry sug-gests that factors other than the economic characteristics of trees them-selves are the primary determinants of the level and source of investment.

Plantation forestry is characterized by high levels of initial investment in relation to those necessary for natural forest management. For exam-ple, in Cote d'Ivoire plantation-grown timber reportedly costs $7.40 a cubic meter, as against $5.60 a cubic meter for timber derived from managed natural forest. These analyses typically ignore or underesti-mate the nonmarket benefits associated with natural forest manage-ment. A valid comparison of plantation and natural forest options demands more sophisticated and comprehensive economic analyses than have been applied in the past. The balance between reliance on and investment in plantations and natural forests will depend on particular circumstances; the level and nature of demands on the forest resource—and the capacity of plantations and natural forests to meet those de-mands—will determine the appropriate balance. In general, it is likely that both forms of forest will have an important role.

Plantation technology

There is a pressing need to develop and disseminate sound plantation technology and tree improvement practices to increase adaptability and productivity. The selection of appropriate species and strains is critical for successful plantation forestry. The largest, cheapest, and fastest gains in most forest tree improvement programs can be made by using the proper species and seed sources within species.

The principal technical requirements for successful plantation forestry are (a) the availability of genetic resources of potentially useful species; (b) the selection of the best-adapted species and strains, their continuing genetic improvement, and the raising of planting stock under favorable nursery conditions; (c) informed scientific observation by competent staff; and (d) adequately paid, well-motivated, qualified staff, available on a long-term basis to manage plantations. The staff should receive support, when necessary, from specialists in relevant disciplines such as anthropology, entomology, genetics, land use planning, and soil science. Concerning the third point, scientific observation, the least that should be done is to monitor growth, nutrition, and health. When necessary this should lead to timely silvicultural interventions so that plantations can achieve their potential. Since these activities involve expense, adequate finance should be available on a continuing basis.

Agroforestry Interventions

Agroforestry holds considerable promise as a sustainable approach to agriculture and land management. But successful agroforestry systems are extremely site specific, and at present it is difficult to prescribe general solutions. There are, however, a number of important ap-proaches that will need to be taken to support further agroforestry interventions in natural resource development projects. These include:

• Greater efforts to incorporate agroforestry components into farm-ing systems-oriented agricultural projects as well as into forestry projects. This has special relevance for those areas between settled agricultural zones and the intact forest—that is, for degraded or converted forests in danger of not being able to support sustainable agriculture or ranching.
• Acceptance that farmers generally prefer multipurpose species to single-purpose species, mixed-cropping systems to single-com-modity systems (for example, woodlots), and passive (labor-sav-ing) agroforestry techniques to active (labor-consuming) techniques
• Greater use of "nonconventional" agroforestry in the reclamation of degraded land: seriously eroded areas (using grasses, shrubs, and trees); saline areas (using salt-tolerant multipurpose wood-lots); impart grass-infested areas; and acidic grasslands and degraded African savannas (using silvipastoral systems)
• Acceptance that the success of agroforestry components will de-pend greatly on a full appreciation of local social and cultural values, customs, and traditions. These include rights to tree and forest products; gender-based distinctions in the allocation of land, labor, and capital; and the complex issues of land and tree tenure. All need to be considered in project planning and design.
• Greater efforts to quantify the short- and long-term benefits of agroforestry under field conditions rather than at research stations
• Greater efforts to support agroforestry research at the field level through national agricultural research programs
• Recognition that NGOs and community groups have an important role in the design and implementation of agroforestry projects, particularly where small-scale, innovative, people-oriented pro-jects are concerned.

A New Approach to Management of Preservation Forests

The old approach to management of preserves tended to treat intact forests as monuments that would persist indefinitely with external care—cleaning up the grounds, neatening the landscape—as though trees were not living things. This approach failed in the past and will fail in the future. For example, in the United States small stands of original forests set aside in preserves are beginning to decline. Visitors trample the soil and reduce regeneration. No area is managed for the next generation of mature forests.

The new approach to management of preserves recognizes that forest ecosystems are dynamic and will change naturally over time. Not only must the intact mature forest be maintained, but the preserve must be large enough so that forest succession takes place within it, with the main representative stages present to provide the habitats associated with these stages.

Professional ecosystem managers, trained in the conservation of biodiversity, must be on staff. Other experts from several disciplines, including hydrology, soils, erosion, geology, and restoration, must be available.

Baseline measurements and continuous ecological monitoring are essential and must be integrated into the management plan. Usually, a small set of factors must be measured and monitored to determine the status of the forest ecosystem. The challenge is to devise a program of measurement that can be sustained over a long period. Although this may be best done through national government agencies (with the exact administrative nature depending on the country), national measure-ment programs could benefit from an international program in ecolog-ical monitoring.

Research to improve understanding of ecosystem dynamics and in-teractions among species is essential and must be integrated into the management plan. The preserve must be planned and managed from a landscape perspective so that various parts of the preserve are put to their best uses. As an example, in Taiwan (China) the La La Shan Nature Preserve, covering approximately 8,000 hectares, was set up for three uses: conservation of habitats for specific endangered species; research and monitoring of natural, intact ecosystems; and creation of large-area ecosystem conservation areas with no habitat modification either for conservation of endangered species or for research. This approach could serve as a model for other preserves. When possible, indigenous people should be involved in the conservation, management, and protection of these areas so that their needs are incorporated and they benefit from the preserve.

APPENDIX C.
Tables

Appendix D.
The OED Report on Forestry: Lessons Learned

The OED's assessment of Bank lending and policy in the forestry sector from 1949 to 1990, "Forestry Development: A Review of Bank Experience," reviewed forestry projects and their components, analyzed development implementation issues, and evaluated sector work. The report sought to put into perspective the economic and social significance of forest development, to provide feedback to guide future policy, procedures, and practice, and to complement recent analyses of Bank involvement in pertinent sectors such as agriculture and rural development, energy, and land management. The report made recommendations for eventual changes in forest sector policies and new proposals for Bank forestry lending. Several of these recommendations are discussed below.

General Issues

Some of the broader issues covered included acknowledging the careful planning, preparation, and processing that forestry projects require, as well as the longer time frames some projects entail. If cooperation and coordination among many line agencies in the planning and implemen-tation of a project are needed, an effective mechanism for coordination is crucial. Monitoring and evaluation are often weak and do not facilitate supervision and final evaluation. Land tenure and potential land use conflicts should be thoroughly investigated during project formulation. In addition, market analysis and market programs should be an integral part of project preparation.

Issues at the national level involve the inadequacy of individual projects for addressing broad sectoral concerns or structural imbalances in the economy. The high ratio of recurrent cost to capital cost is a major problem in sustaining forestry projects at the country level, particularly in view of the pressures to reduce public expenditures. Governments alone do not have the capacity to tackle single-handedly problems of wood deficits and forest depletion. In addition, the report noted that countries should develop buffer zones around remaining forest areas and that pricing policies should adequately reflect the environmental benefits obtained from forests.

Some of these lessons have important implications for policy formu-lation. Many supervision reports have emphasized that most forestry projects face serious financial problems. Although it is recognized that project performance depends on how macroeconomic policies affect both land use and management of existing forests, no comprehensive study of intersectoral linkages has been made. Moreover, there is no evidence that forest sector concerns are systematically incorporated into macroeconomic policy formulation and reform.

The OED report highlighted the importance of:

• Strengthening the role of institutions, with particular emphasis on property rights

• Developing organizational arrangements

• Improving complementary services (for example, research and extension and marketing)

• Recognizing intersectoral and macroeconomic linkages that affect the sector

• Centering operations around land use

• Increasing the capability inside and outside the Bank for assessing natural resources

• Finding new lending instruments, with special emphasis on financing.

Experience suggests that operations in the l990s should place higher priority on the program than on the discrete project type. The success of sector loans will depend on a sector policy, a comprehensive forest management component, favorable macroeconomic policies, a major infusion of resources for human capital development, and a clear recog-nition of the interplay among the forest, people, and culture.

The OED study also recommended that (a) every project in the sector be conditioned to conform to a country forest sector policy; (b) a forest sector assessment unit be established to improve Bank knowledge about natural systems affected by other sectoral interventions; and (c) new lending instruments be created for projects that are not immediately or directly productive, such as forest management operations.

Lessons Learned from Specific Project Components

The OED report selected five components of free-standing forestry pro-jects for special analysis: plantations, nurseries, farm and community forestry, natural forest management, and watershed rehabilitation or protection. The following sections summarize the OED’s findings regard-ing each component.

Plantations

Before large-scale planting begins, the technological soundness of the chosen species mix should be ensured. Often this means allowing the trial to run long enough to determine changes in growth rates as the stand ages and to monitor possible disease or pest infestation problems that may not emerge until later in the growth cycle. The trees chosen should represent a multicriteria mix that takes into account, for example, speed of growth, fire or pest resistance, quality of wood for industrial uses, fodder potential, income generation, and contribution to the pres-ervation of genetic diversity. Indigenous tree varieties should be given high priority. Marketing analyses, soil surveys, species research, and plantation trials should be conducted during project formulation so that an appropriate species mix is chosen for large-scale planting. Trial plantations should be small and preferably near existing plantation programs to maximize access to expertise and minimize infrastructure costs. Investigating land use and land tenure as part of project prepara-tion is particularly important in plantation projects.

Sufficient attention should be given to maintaining plantations, par-ticularly during the first few years, even if planting targets suffer. The increased growth rate that results from weeding apparently compen-sates for the additional costs. A fire prevention or fire-fighting capability that includes providing equipment and designing a fire protection and control program needs to be established early. (Adequate weeding is also important for fire prevention.) Close monitoring of these programs should be a priority in fire-prone areas to ensure that forestry protection measures are enforced correctly and promptly.

Lower-cost alternatives to clear-felling secondary forests to establish plantations should be explored (examples are reseeding logged-out forests, managing natural forests to allow regeneration of more valuable timber, and providing private sector incentives for reforestation). There is a need for greater attention to and research on thinning, processing, and marketing secondary tree species and on secondary products (such as fuelwood and charcoal) that could increase benefits. A careful analysis of the marketing and trade possibilities of potential products should be part of project formulation.

Finally, solutions to shortages of energy (fuelwood) and wood prod-ucts and to environmental degradation often lie beyond the sector and may require a multisectoral approach that includes modifying basic policies and increasing private sector participation.

Nurseries

A large-scale, nationwide nursery program should not be carried out until a pilot program has been instituted to resolve design flaws, partic-ularly where retail nurseries are a new concept and the forestry depart-ment has no prior experience with them. The location of nurseries should be based on a thorough supply-and-demand analysis that identifies wood-deficit areas and accessibility of sites, among other factors.

A good approach is to establish nurseries on a temporary basis until farmer response is sufficient to justify upgrading to permanent status. To reduce the transport costs of rural consumers, it is preferable to have numerous small nurseries rather than a few large ones. Diversified nursery production with more species and types of trees will increase demand. Production costs will be decreased by shifting from purely potted stock to more than half bareroot stock. Sound communication with rural communities through good information and extension (which is also facilitated by having a large number of smaller nurseries) is an effective marketing strategy and allows nurseries to respond rapidly to changes in species preference.

Seedlings should be sold rather than given away. Although farmers are quite willing to pay for seedlings, they are more selective than had been anticipated. A rural nursery program is an appropriate way of making rural populations self-sufficient in fuelwood by offering seed-lings at affordable prices. High costs of production may be addressed through greater use of labor and increases in production volume. Nurs-eries should not be set up without establishing extension to advise farmers on planting and tending techniques, planting distance, planting seasons, protective activities, and so on. Also, nurseries require a sup-portive policy environment; they cannot be economically viable unless incentives are provided for planting trees. Attention should be given to control and protection of natural forests, to adequate producer prices for wood products, and to a strong revenue collection system.

Farm and community forestry

Studies indicate that rural forestry development should be based on the complete participation of the rural population (family tree plantations) rather than on community plantations and that the "top down" ap-proach should be avoided. An approach that encourages smallholders to grow trees by providing them with seedlings, extension services, market guarantees for their product, and credit remains viable and is worthy of public sector support. A rigorous approach should be used, however, in evaluating the long-term viability and commitment of private companies that might provide markets for smallholder produce.

Project activities should achieve socioeconomic as well as physical objectives. Special financing arrangements for smallholder or subsis-tence farmers might be needed. Even for family farms, labor and trans-port costs should be studied and, if appropriate, provision for these expenses should be made in the subloans. The technical packages pro-moted in farm forestry should be thoroughly researched. There is a crucial need for more attractive and adaptable technical packages and a more participatory and multisectoral approach to rural forestry. The technical packages should be appropriate to the relevant conditions (such as soil and management).

Extension is an important part of farm forestry. Where private exten-sion is weak, alternative government extension services should be ar-ranged. Farm forestry programs should not be attempted without a supportive policy environment. Supplying farmers with subsidized seedlings is not sufficient. As with nurseries, the control and protection of natural forests, adequate producer prices for wood products, and a strong revenue collection system must be examined. More effort needs to be put into project design and supervision to monitor the survival and use of distributed seedlings. Techniques for using trees in cultivated areas should be considered as tools for intensifying production systems. This intensification can be achieved only in conjunction with a manage-ment plan for village lands, conceived and carried out with the partici-pation of the local population. Such land use plans should be comprehensive, with particular emphasis on all the social and legal problems posed by the utilization of trees in production systems. More-over, future rural forestry investments should include a comprehensive approach to integrate forestry, agriculture, and pastoralism.

Management of natural forests

Experience has not been sufficiently satisfactory to warrant the indiscriminate replication of this type of component. In view of the urgent need to manage existing forest resources, it will be essential to obtain a clear commitment from the government to ensure proper implementation. Experience shows that in carrying out management-related tasks, in defin-ing and implementing the necessary instruments (including institutional reforms), and in assessing the optimal pace during implementation, the government has the absolute and relative comparative advantage.

More training may be needed at the national and local levels. Good management work plans require comprehensive resource assessment studies, including ground survey work. Efforts must continue on im-proved management of fire and on techniques for the recovery, care, and exploitation of natural forests. Concerns should go beyond the produc-tion of wood to encompass pasture management and conservation of flora and fauna.

There is a need for greater understanding of natural forests to make possible sound forest management. This may not significantly increase production, given the magnitude of the need, but it will significantly affect environmental protection.

Watershed rehabilitation or protection

If a watershed area is being put to multiple uses that may affect revege-tation, components for controlling or managing these uses should be implemented prior to revegetation attempts. It should be assumed, unless there is significant contradictory evidence, that the most ecolog-ically appropriate, technically sound, and economically viable approach to flood attenuation is through watershed rehabilitation rather than through dam storage of water. According to a project completion report, watershed stabilization through rehabilitation that reduces the siltation rates of reservoirs to economically acceptable levels moderates the tor-rential, sediment-bearing nature of floods so substantially that little room is left for justifying additional flood attenuation through dam construction. In watershed areas with existing land use, substantial emphasis should be placed on extension, information, and public rela-tions efforts toward local farmers to elicit their cooperation. Mainte-nance activities should be adequately planned and should be implemented in several watershed projects; costs, in both money and time, should be realistically estimated.

Glossary

Afforestation. The planting of trees in unforested areas.

Agroforestry. Land use system in which woody perennials are used on the same land as agricultural crops or livestock in some form of spatial arrangement or temporal sequence.

Carbon fixation;carbon sequestration. The conversion byplants, through photosyn-thesis, of atmospheric carbon dioxide into organic compounds.

Closed forest. Forest in which the stand density is greater than 20 percent of the area and tree crowns approach general contact with one another.

Commercial logging Extraction of timber in large quantities for industrial or export markets.

Common property. Tenure system whereby resources are collectively owned and managed and non-owners are excluded from access to the resources.

Conifers; coniferous species. Softwood species, as distinguished from broad-leaved (hardwood) species; mostly evergreens.

Conservation. Rational and prudent management of natural resources to achieve the greatest benefit while maintaining the Potential of the resource to meet future needs.

Conversion forest. Forest assigned for conversion to agriculture or other nonforest use.

Deforestation The clearing of forests and the conversion of land to nonforest uses.

Degradation Biological, chemical, and physical processes that result in loss of the productive potential of natural resources in areas that remain classified as forests. Degradation may be permanent, although some forests may recover naturally or with human assistance.

Depletion Reduction in forest area or volume as a result of deforestation.

Desertification Degradation of the land that ultimately leads to desert-like condi-tions.

Designated forest. Forest legally set aside for preservation or production.

Ecotourism Nature tourism.

Environmental services. Beneficial functions performed bynatural forest ecosystems, including the maintenance of biodiversity, protection of soil and water resources moderation of climate, influence on rainfall, sequestering of carbon dioxide, provision of habitat for wildlife, and maintenance of the earth's natural balance.

Exotic species. Species introduced from another ecological zone; usually opposite of indigenous.

Externality. A cost (or a benefit) of an economic activity by one party that is unintentionally imposed on (or received by) another party without compensation (or payment) and that leads to inefficiencies in competitive markets.

Farm forestry. People-oriented forestry that is carried out on private farmlands. Related but not synonymous terms are agroforestry, community forestry, and social forestry.

Forest fallow; bush fallow. Area dominated by woody vegetation after having been cleared and used for shifting cultivation.

Hardwood. Wood of broadleaved trees, as distinct from softwood (produced by conifers).

Industrlal plantation. Stands of trees raised for the production of industrial forest products (for example, sawlogs, veneer logs, pulpwood, poles and pitprops, and wattle bark).

Industrial forestry. Industrial plantations and forest industry.

Lopping. Pruning or pollarding as a means of harvesting small-diameter branches, typically for firewood or leaf fodder.

Market failure. A deviation from the conditions required for the efficient allocation of resources by a purely competitive market.

Nonwood products. Tangible minor forest products, such as fruit, nuts, and bushmeat

Open access. The absence of ownership claims over resources, permitting and leading to uncontrolled and excessive attempts at appropriation and use.

Open forest. Forest in which the tree canopy layer is discontinuous but covers at least 10 percent of the area and in which the grass layer is continuous.

Other wooded area; woodland. Area that has some forest characteristics but does not meet the definition of forest given above. Includes areas occupied by windbreaks groups of trees, fallow land, and shrubland.

Poles. Small-diameter wood used in unprocessed form for construction, fenceposts, and other purposes.

Pollarding. Cutting the branches of a tree to promote the growth of a dense head of foliage.

Preservation forest. Forest designated for total protection of representative forest ecosystems in which all forms of extraction are prohibited.

Primary forest. Relatively intact forest that has been essentially unmodified by human activity for the past sixty to eighty years.

Production forest. Forest designated for sustainable production of forest products.

Protection forest. Forest designated for stabilization of mountain slopes, upland watersheds, fragile lands, reservoirs, and catchment areas. Controlled sustainable extraction of nonwood products could be allowed.

Reforestation. The replacement of trees in cut-over forest areas.

Secondary forest. Forest that is subject to a light cycle of shifting cultivation or to various intensities of logging but that still contains indigenous trees and shrubs.

Selective felling; selective cutting. Harvesting of only a small proportion of the standing crop; the opposite of clearfelling.

Shelterwood system. A silvicultural system in which an existing stand of trees is removed in two or more fellings to encourage regeneration in the shelter of the remaining trees.

Shifting cultivation. Farming system in which land is periodically cleared, farmed, and then returned to fallow; synonymous with slash-and-burn or swidden agricul-ture.

Shrubland; brushland; scrubland. An area more than 20 percent of which is covered by shrubs or stunted trees and that is not primarily used for agricultural or other nonforest purposes, such as grazing of domestic animals.

Social forestry. Farm forestry and community forestry.

Softwood. Wood from conifers, as distinguished from hardwood (from broadleaved trees).

Stumpage; royalty. Fee or price of standing trees before logging.

Sustainable development. Development that meets present needs without compro-mising the ability of future generations to meet their own needs.

Sustainable management. Utilization of forests without undermining their use by present and future generations. Different systems of management are required for each category of forest, depending on the intended output.

Sustained yield. Production of forest products with an approximate annual balance between net growth and harvest.

Tropical dry forest. Open forest with continuous grass cover; distinguished from other tropical forests by distinct seasonality and low rainfall. Includes woody savan-nas and shrubland.

Tropical moist forest. Forest situated in areas receiving not less than 100 millimeters of rain in any month for two out of three years, with a mean annual temperature of 24°C or higher; mostly low-lying, generally closed. Subdivided into tropical rain forest and tropical moist deciduous forest.

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