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Taungya systems from biologiocal and production viewpoints
Taungya systems: Socio-economic prospects and
limitations
Establishment of forest villages in Gabon
Taungya
in Sierra Leone
Taungya
practices in Togo
Development trends in taungya systems in the
moist lowland forest of Nigeria between 1975 and 1980
Food crop yield under gmelina plantations in
southern Nigeria
Summary of discussion: Taungya systems from
biological and production viewpoints
Taungya systems: Socio-economic prospects and limitations
E.E. Enabor, J.A. Okojie, and I. Verinumbe
Department of Forest Resources Management, University of Ibadan,
and International Institute of Tropical Agriculture, Ibadan,
Nigeria
Abstract
Taungya systems embrace multiple land-use practices involving joint production of forestry and agricultural crops In the tropics, land is a most important factor of production and there is overwhelming dependence of the population on land for livelihood. The introduction of taungya has alleviated the problems created by the wasteful use of land under the traditional agricultural production systems, increased food supplies, and significantly con" tributed to the socio-economic well-being of the rural population. It is indicated in this paper that socio-economic factors favour continued development of taungya in the tropics, particularly if the limitations of labour and capital can be removed through adequate government support of the programmes.
Introduction
Land is a basic, if not the most important, factor of production in the tropics. The primary occupation of the people is agriculture, which employs more than 60 per cent of the active labour force. Agriculture constitutes the dominant sector of tropical economies, not only as the principal source of food for the majority of the population but also in terms of the sector's share of total national production, which frequently exceeds 50 per cent. For many tropical countries, development prospects depend on the prices of agricultural and forestry products in international markets.
The past concentration on, and bias towards, export cash" crop production in the tropics was a major factor in the incidence of food shortages and malnutrition, the true dimensions of which are only now being appreciated (Okurume 1970). Data available from FAO (1976) indicate that the annual growth rate of food production per person in developing countries fell from 0.6 per cent in 1961-1970 to 0.2 per cent in 1971-1975. In Africa, the annual growth rate in 1971-1975 was-2.1 per cent compared with 0.4 per cent in 1961-1970.
Unless these trends are reversed, the developing countries of the tropics will be confronted by the spectre of chronic food shortages, widespread malnutrition, and mass starvation by the end of the twentieth century.
Tropical agriculture is particularly extensive, relying on a system of shifting cultivation or rotational agriculture whereby the farmers cultivate a piece of land for a few years, abandon it to fallow to regain fertility, and move on to cultivate another piece of land. They may cultivate several pieces of land successively before returning to recultivate the first piece of land at the end of the cultivation cycle. Ordinarily, shifting cultivation requires a large amount of land per farming family,! and its successful practice depends on virtually unlimited land availability or a relatively small farming population (Kio 1972).
The population of the tropics has grown very rapidly in the last two decades, averaging 2.5 per cent a year compared with 1 per cent in the developed countries of the temperate region (UN 1979). Given their small industrial sectors and their limited capacity to absorb excess labour in agriculture, developing countries have faced continuing fragmentation of farm units to accommodate requirements of new families. The institutional framework of land use in most tropical countries directly promotes such fragmentation of holdings.
The fragmentation of holdings and the prevailing institutional framework that does not fully view land as a factor of production have contributed to declining agricultural productivity and food shortages in the tropics. Equally important are the failure to introduce appropriate technologies (superior farming implements, seed varieties, and production techniques) and the inefficient organization of agricultural production. The causes of declining agricultural productivity with particular reference to Nigeria have been well documented by Olayide (1973). To overcome the constraints would require a revolution in agricultural production in the tropics, an event likely to occur only in the distant future.
Solutions to the defects of shifting cultivation as a form of extensive agriculture have been provided by the system known as taungya-combined production of forestry and agricultural crops on forest lands. King (1968) found that the system has been practiced for a long time and existed at some time in all the five continents. He also indicated that, despite the differences in terms or labels used, the taungya system always exhibited certain basic attributes and required some preconditions for its adoption. The preconditions, such as land hunger and low standard of living of the population, are clearly socio-economic in nature. The fact that the system is virtually extinct in the economically advanced countries supports this assertion.
The socio-economic environment is central to the prospects and limitations of taungya systems. Indeed, King (1968) concluded that the system was self-terminating once a country achieved a certain level of economic development.
Socio-economics in the Development of Taungya
The introduction of the taungya system into the humid tropics was a response to various socio-economic factors. For example, in Nigeria a major objective was to solve the problem of high cost of forest regeneration (Enabor 1979). In Ghana, the objective was to solve the existing land hunger problem in the rural areas (Amissah 1978). Whatever the reasons for introducing taungya, King (1968) insisted that the successful establishment and development of taungya depended on the pre-existence of land hunger, underemployment, and low standards of living among the rural communities. Apart from these three prerequisites, other socio-economic factors contributing to the development of taungya include population growth, land availability, farm labour supply, food supply, income-generating potential, availability of infrastructural facilities and organizational institutions.
In Burma, where taungya originated, it was used mainly as a means of regenerating both the soil and the forest by employing and improving upon shifting cultivation. It was essentially a method of shifting cultivation because forest land was cleared, farmed for a few years, and allowed to revert to forest so that fertility was restored naturally. It was an improved system because selected tree species such as Casuarina equisetifolia and Leucaena glauca were sometimes planted to assist in re-establishing the forest fallow (Nao 1978). The indication is that a low population density and a long fallow period were required for the system to be successfully practiced. Under the present high population densities it is doubtful that the system in its original form would succeed in many tropical countries.
The modern taungya system seems to differ significantly from the original concept. The practice has been reserved to forest estates, and rapidly growing rural populations have often put pressure on foresters and forced them to adopt taungya within the estates. Kio (1972) concluded that until the industrialization of tropical countries becomes large enough to absorb the increasing rural population, pressure on forest estates by farmers would continue. The greater the pressure on forest lands, the more taungya would be sustained.
At the time when the present forest estates of many tropical countries were constituted, land was abundant, forests dominated the landscape, and shifting cultivation was successfully practiced. Agricultural expansion, introduction of permanent cash crops, and over-cultivation of available arable land have resulted in rapid soil deterioration and lower crop productivity in the unreserved land areas. The reserved forest lands have remained fertile, thus constituting highly productive farmland potential. Such imbalance in soil fertility between reserved and unreserved areas may facilitate successful development of taungya. King (1968) reported that, despite the existence of unoccupied and uncultivated land outside reserves in Uganda, farmers still participated in taungya because of higher fertility of the reserved land. Similarly, Lowe (1974) stressed that one of the major reasons that farmers participated in taungya in Nigeria was the opportunity to use the residual fertility of newly cleared land.
With population growth, an increasing number of farmers have found it difficult to acquire more land for farming. Immigrant labour required for the various forest operations may not get land outside the reserve to grow food to meet their own consumption requirements and that of their families. The introduction of taungya would be a big relief to such farmers. Thus, in some parts of south-west Nigeria, Ijalana (1979) found immigrant fishermen (llajes) constituting about 90 per cent of taungya farmers because they could not get land outside the reserves. Nigerians working their way to or from Mecca have similarly been mentioned by King (1968).
In general, where arable land is too scarce to permit agriculture or forestry as single land uses, taungya will develop. Over the past 54 Years in Nigeria, the adoption of taungya has constituted an effective means of providing more farmland to the farmer and, at the same time, transforming the natural forest into more productive forest plantations at relatively low direct cost to government.
Labour and Other Inputs
The growing of both agricultural and forestry crops is involved in the taungya system. The activity is labour-intensive, especially as modern farming techniques are at present nonexistent in taungya operations. For a successful implementation of taungya, the supply of labour must be ensured, In this way the absence of alternative non-farm occupations also favours taungya. Some farmers in southwest Nigeria were apparently unwilling to practice taungya because they were not unemployed (King 1968).
Several authors, including Mergen (1978) and Nao (1978), have contended that the taungya farmer is exploited by participating in the establishment of plantations without being adequately rewarded. King (1968) went further, to suggest a sharing of the savings in the cost of establishing the forest plantation between the farmer and the forester. The thinking is that if there are other job opportunities in the rural areas, the farmer may prefer them. However, 99 per cent of farmers in south-west Nigeria reported that they gained from participating in taungya (Kio and Bada 1981). The indication is that even if farmers are being exploited they are not aware of it and they are quite willing to participate.
Taungya, whether traditional or departmental, 4 is an arduous task. The labour has to be drawn from the existing pool of farm workers because out-migration to the urban areas has depleted other sources. As long as out-migration continues taungya will suffer a drain in the most productive labour force, the young men and women. In order to sustain the system rural life must be made attractive and comparable to urban conditions so that rural labour is retained. The introduction and success of the departmental taungya system in southeast Nigeria seems to be a manifestation of the importance of this factor in the development of taungya (Enabor and Adeyoju 1975). What still remains largely unsolved is the introduction of improved farming techniques so that the work becomes less arduous and the system more productive.
Food Supply and Income Generation
Nao (1978) estimated that taungya systems in Nigeria have directly provided enough food for about 700,000 people, constituting about 1 per cent of the country's food needs. In Thailand the indication is that taungya farmers produce enough food to feed themselves and sell the surplus to the market, and in China, taungya farmers contirbute about 56 per cent of the country's food requirements
It is not clear from these figures whether the taungya farmers enjoy a higher standard of living than their nonparticipating counterparts. It is sometimes argued that farmers would be more willing to participate in taungya only if their standard of living, measured by level of income,were improved. However, King (1968) maintained that the taungya farmers' income is improved only if they are provided with wageearning employment in the forest plantation. In this respect departmental taungya would satisfy the income requirement for the successful development of taungya, because it ensures regular income comparable with that obtainable in other sectors of the economy.
Under the traditional taungya system, income generation is left entirely in the hands of the farmer, who may find it difficult to get a ready market for the produce. However, Kio and Bada (1981) found that although most of the taungya farmers sold less than half of the total crop volume harvested, they obtained between N500 and N2,000 per year. Also, Lowe (1974) maintained that most of the food produced by taungya farmers is consumed locally, yet farmers may earn between N600 and N800 a year if they concentrate on yam production. If maize and cassava are produced, the estimated income would be N100-N200. Another estimate by Enabor (1979) was that per capita income of taungya farmers in Nigeria is about N72, which is below the N90 estimated for urban centres but well above the N30 estimated for rural areas.
Despite such improved income estimates for the taungya farmer, Olawoye (1975) contended that the living conditions of the traditional taungya farmers have not improved as compared with those of other rural villagers. In contrast, the departmental taungya farmer has enjoyed substantial benefits in terms of provision of infrastructure and other amenities. The indication is that, although a low standard of living is required as a prerequisite for the introduction of taungya, its continued successful development depends on the extent to which it improves the standard of living of the farmer. As long as improvement does not occur, the capable farmer will look to the urban centres in search of a better living standard, the practice of taungya being left to less efficient hands.
Infrastructural Facilities and Social Amenities
Some of the major infrastructural facilities that may affect the development of taungya systems include transport, marketing, and storage facilities. To the farmers who do not have means of transportation and have to walk to the farm, the distance from home to the farm is a major determinant of their level of participation in taungya. In well-organized taungya systems accommodation at very convenient locations may be provided for the farmers.
Where transport facilities are readily available or where land shortage is acute, farm distance is less important in determining the farmer's participation. For example, King (1968) showed that farmers in Trinidad travelled up to 16 km to participate in taungya because transportation was relatively cheap and easy. In Kerala (India), there was no distance limit because of the acute land shortage problem and low standard of living of the farmers. In Nigeria, Ijalana (1979) found that taungya farmers travelled between 3 and 6 km by motor vehicle or bicyle to the farms.
Distance may not constitute a limitation to participation but it surely has an effect on productivity. Farmers who travel long distances may reach the farm already exhausted. They may arrive late and have little time to participate before closing time. Thus Mergen (1978) estimated that 3-5 km should be the maximum walking distance.
The improved crop yield obtained from taungya farms is not meaningful if there is no means of storing the excess food produced or transporting it to the market for sale. Farmers can only be encouraged to produce more if they get reasonable returns.
The availability of schools, sanitary and health facilities may encourage farmers, particularly young ones, to stay in the rural areas and participate in taungya rather than migrate to the cities. Moreover, such facilities would improve the farmers' capabilities and make them more contented and productive workers.
Easy access to credit facilities for taungya farmers would enable them to improve their methods of cultivation and to store, process, and sell their produce at the right time to obtain maximum profit. Credit facilities are also necessary to enable farmers to acquire improved farm inputs, such as fertilizers, herbicides, and farm machinery.
Prospects and Limitations
Numerous studies confirm the positive role of the taungya system in augmenting food supplies and fostering the socioeconomic improvement of rural communities in tropical countries. The system has also been instrumental in preserving forests. The prospects for the taungya system hinge on the continued interest of the farmers and the foresters in its maintenance, aided by the government.
The socio-economic prospects of taungya systems in the tropics depend on such factors as development trends of the economy in general (and of agriculture in particular), population growth, unemployment, income-generating potential, effectiveness of forest management, and the role of government in providing necessary incentives.
The disappointing development performance (UN 1978) of tropical countries has prompted a rethinking of growth strategies to solve the mounting problems of poverty, ignorance, disease, and malnutrition. In the 1980s emphasis has shifted to self-reliance and self-sustaining economic growth in which high priority is given to food and agriculture, raw materials, and natural resource development (ECA 1980).
The economic growth strategy demands action by government to improve agricultural productivity and rural income, provide infrastructure and social amenities, and promote diversification of employment opportunities that will stabilize rural communities. In the short term, measures to stimulate rural development must focus on the smallholder farmers rather than on large-scale capital-intensive agricultural projects. The taungya system should constitute an ideal development tool. Its adoption on a large scale should greatly expand food and wood supplies, increase rural employment opportunities, and raise living standards. Many of the inputs to a successful rural development programme, such as improved seed varieties, fertilizer, infrastructure, and social amenities, are complementary to the operation of the taungya system.
At the level of the smallholder, income considerations are the dominant concern. The income prospects depend in turn on such factors as soil fertility, crop combinations, production costs, and prices, as well as on the efficiency of harvesting, transporting, and marketing. While the taungya farmer initially has access to highly fertile soil in newly cleared areas (Lowe 1974), the soil fertility may be depleted after two or three years, depending on the particular crop combinations used and cultural practices. Fertilizers or other inputs must be used to maintain soil fertility and high yields. The effects of combining crops on each other as well as on soil fertility in forest lands need to be investigated. There are signs, however, that more flexibility is being introduced into the system, as farmers in some countries are given permission to grow fodder crops and cash crops such as cocoa and coffee, and raise livestock.
Production costs also affect income prospects. Under the traditional taungya system, the bulk of the production costs to the farmer is implicit and consists of the labour provided by himself and members of his family.
The farmer's needs for cash will probably increase under a well-developed taungya system for the purchase of superior seed varieties, farm equipment and tools, and services of hired labour during intensive operations such as land preparation and harvesting.
With population growth and improved living standards, the prices of food and livestock feeds are bound to rise. Taungya farmers are thus assured of good prices for their output, especially where they are able to transport and market their own products. In Nigeria, where good road systems have been extended to many rural communities, farmers can now convey their surplus produce to markets about 100 km away, obtain good prices, and return home the same day. They can now dispense with the services of intermediaries, who, in the past, absorbed the bulk of the profits from production efforts.
Several estimates of income earned by the farmer under taungya have been made. In Nigeria, the estimates of annual income range from N50 (Ball 1977) to N600 (Okojie 1975). In Zambia, the profit (net present value) from maize intercropped with pines in an industrial plantation increased 7 per cent in one year compared with the pure pine plantation (Kufakwandi 1980). Although the figures vary widely, they provide evidence that the farmers inside taungya earn higher incomes than those outside. A majority (55 per cent) of farmers interviewed in Oyo State, Nigeria, reported definite improvements in income (Kio and Bada 1981). Taungya is especially profitable for farmers who obtain supplementary employment in forestry or have privileged access to forests to hunt, collect wood for sale, gather fruits and nuts, or harvest other forest produce freely. If income-generating potential alone were considered, the taungya system's prospects would be bright.
For taungya systems to be successful, however, it is necessary to have a regular supply of labour. The estimated agricultural labour force of developing countries rose from 648.1 million in 1965 to 709.2 million in 1975 (FAO 1980), representing 31 per cent and 34 per cent, respectively, of the total rural population. At present a high proportion of the labour force in tropical agriculture is unemployed or under-employed. The taungya system provides a unique and attractive opportunity for absorption of unemployed rural labour. In particular, it represents the only alternative available to landless rural farmers.
Ironically, however, many unemployed farmers are reluctant to participate in taungya. First, the majority of young potential farmers in rural areas find rural life dull and uninteresting. They are migrating to urban centres, where life is less arduous and monotonous, in search of jobs. Rural-urban migration on a large scale has been encouraged by the worsening rural-urban terms of trade (FAO 1980). Thus, the majority of farmers participating in taungya in the tropics are people aged 40 years and over (Kio and Bada 1981). A high proportion of such farmers tend to be under-nourished and in a poor state of health, so their productivity is low (Enabor 1978). Some unemployed farmers are willing but unable to participate in taungya because they lack the necessary inputs to cultivate the land allocated to them in forest reserves. The youth must be retained in the rural areas by the creation of more attractive living conditions. To some extent, the establishment of departmental taungya schemes based on integrated forest villages provided with all the basic social amenities has enhanced participation of younger farmers in taungya systems (Enabor and Adeyoju 1975),
The effectiveness of forest management also affects the prospects for taungya in the tropics. The objective of forestland management under taungya is to obtain the maximum rent from the soil under use. This requires viewing the system as an integrated joint enterprise. Profit is to be maximized for the whole enterprise rather than for the component parts (Enabor 1978). Currently, forest management in the tropics is still very weak or ineffective and lacks necessary information, trained personnel, and adequate financial inputs. It is, therefore, not surprising that most foresters distrust farmers who, in turn, are discouraged by the host of restrictive regulations in taungya schemes. A possible solution to the problem is to strengthen forest management with adequate legislation and supply of productive inputs. Alternatives are: (1) departmental taungya, in which the forestry department owns both the agricultural and forest crops, or (2) agro-forestry, where total ownership rests with the farmer.
King (1968) postulated that the taungya system would die a natural death once farmers' incomes reached a sufficiently high level. However, a survey in Ando State indicated that highincome farmers were more interested in agro-forestry than were low-income farmers (Ijalana 1979). Taungya in the modern sense is a multi-product enterprise rather than a system that provides supplementary income through a forestland tenancy. There is evidence that the concept of agro-forestry as a rational and profitable multiple land use is gaining increased attention in some economically advanced countries (anon. 1978).
The most important limitation of the taungya system is the lack of adequate inputs of land, labour, and capital. An adequate supply of land is particularly critical to traditional taungya confined to forest reserves, because in most tropical countries the chances of further expansion of the land area under reserves are slim indeed. In practice, only parts of the forest estate will be effectively available for taungya. With time the problem of land hunger is bound to surface as the population of taungya-dependent communities expands. Where the physical availability of land for taungya is not limiting, the difficulty of transportation would still proscribe the area that farmers can effectively cultivate.
The problem of shortage of labour for taungya systems in the tropics was mentioned above. The available evidence indicates that more and more farmers are relying on hired wage labour to perform essential farm tasks. On the other hand, many more farmers are unable to afford high cash wages, and therefore spend longer hours in cultivating their food crops. Less time is thus available for planting and tending forest tree crops from which they receive no direct income. Increased capital resources of farmers would enable them to recruit the hired wage labour needed to effectively cultivate an optimum farm size under the taungya system. Loans for this purpose should be granted to the farmers by the forestry departments, which are in a position to ensure repayment at the time of harvesting and sale of the farmers' crop.
Another limitation of the taungya system is management. There is an acute shortage of the funds and trained personnel needed to institute effective management. Necessary information on performance of alternative crop combinations and their impact on the soil is lacking. So foresters may prefer reversion to monoculture, with which they are more familiar, or to natural regeneration. Some recent studies (Kio 1978) have concluded that natural regeneration systems are at least as productive as artificial plantations, and they do not incur the loss of vital ecological benefits.
The limitations of taungya systems in the tropics are more those of operational constraints than those of concept and meaning. With real economic progress, the constraints should gradually disappear so that the practice can be rationalized into a permanent and profitable system of land use.
The socio-economic factors favour the survival and expansion of taungya systems in the tropics, at least up to the end of the present century, provided the practice is backed by adequate government support. As Adeyoju (1980) has stressed: The future of agro-forestry depends not merely on the quantity and value of joint products arising from the enterprise, but largely on the package of sociopolitical strategies built into the programmes.
Establishment of forest villages in Gabon
J. Leroy Deval and Faustin Legault
Directors of Reforestation, Libreville, Gabon
Abstract
Gabon is a country whose dense forests constitute the main natural resource. The forests are stocked mainly with okoume (Aucoumea klainiana) and, because they have been exploited by industry, the government has established a reforestation programme of natural stands. This paper describes the means used to attain this objective and the results of initial endeavours. The conclusions include recommendations for improving the programme.
Gabon-A Country of Forests
Seventy-five per cent of the area of Gabon is covered by dense, humid, evergreen forest of low and medium altitude, while 15 per cent of the country is savanna. Gabon produces a great deal of wood (particularly okoume, Aucoumea klainiana) and its forests have been subjected to intense exploitation for more than half a century. For many years the government has been working on a reforestation programme in over-exploited forests and an improvement programme for dense natural okoume stands.
The vacant, unclaimed forests of Gabon and the reforestation areas belong to the government and constitute part of its private domain. This is the basic legal status governing the forests but rural communities, which account for 86 per cent of the population, exercise their customary right to use the government-owned forest, a right strictly limited to meeting the personal and community needs of users (collecting firewood and building materials, picking medicinal and edible plants, and so on).
In this way, the forest is a reservoir from which rural people can obtain basic essentials. Various food-producing crops are also raised in these forests. This situation dates back to precolonial times and, unfortunately, has not developed since then. This explains why rural communities have failed to evolve. For obvious financial reasons, the forests are systematically exposed to a well-established exploitation operation, with solid financial backing. The forestry activities of big businesses do not meet the fundamental rural development criteria, namely that the basic structure for any development effort must be the village.
Forestry regulations in effect in Gabon have provided for a forestry permit which allows rural people to acquire a certain amount of forest land, if they meet fairly simple requirements. These provisions have actually favoured the development of some geographically superior areas. The permits apply to what are known as family-cutting areas, which are most sought after in zones rich in okoume located close to transportation routes. This made exploitation inexpensive and required only rural manpower. Over the years, however, these activities, along with demographic pressure and intensified exploitation, have led to forest shrinkage. Favourable zones are now in distant locations and are becoming rare. Nowadays, this type of permit has lost its original character. It has been diverted from the traditional practice and has been used to benefit tenant-farming contracts which, as they become more common, make the lot-owner a "shareholder" in the forest. This runs counter to efforts in Gabon to develop a class of native contractors in rural areas.
Reforestation Centres
The most important activity of reforestation centres is the creation of artificial stocks of okoume. Studies and research on forest ecology and on the biology of this species have made it possible to develop a sophisticated silviculture technique. The artificial regeneration of the stocks of this species no longer poses major problems. Twenty-six thousand hectares of okoume have been planted so far.
The establishment of a reforestation centre always begins with plans for a road network and home construction. Under normal circumstances, each of these centres consists of a staff of between 100 and 400 people. Including families, approximately 1,000 people live in a centre. The staff should be broken down as follows: 70 per cent unskilled workers; 25 per cent technicians (experts); and 5 per cent training personnel.
In an effort to alleviate insufficient food crop yields among elderly villagers and the families of staff (who are mainly seeking self-sufficiency), the reforestation authorities decided to introduce intercropping in the reforestation plots. they had both social and economic objectives in establishing an agro-forestry system. The social objective was to encourage the population to participate in the artificial regeneration of the forest, and thereby to solve the conflicts of interest that often divide forestry specialists and farmers when the latter feel they are being deprived of arable land and are not benefiting from reforestation activities. The economic objective was to increase the quality and value of the plantations.
An agro-forestry solution was thus chosen, aimed at increasing the value of plantations by the incorporation of food crops. There was a choice between two types of crops: the traditional food crops such as cassava, cocoyam, and corn; and the profitable cash crops such as coffee, cocoa, oil palm, and bananas.
For the traditional food crops, experiments were conducted on the Nkoulounga reserve located north-east of Libreville; cocoyam and cassava were planted between rows of okoume, either the same Year as the okoume was planted or the following year. The okoumes were planted 3 x 3 m, 5 x 5 m, and 6 x 6 m apart. An attempt was also made to introduce okoume in a one-year-old cassava plantation where the okoumes were planted 12 x 12 m apart. It soon became apparent that the requirements of the okoumes and the food crops were incompatible. To grow well, okoume needs a lateral screen of young forest undergrowth to protect its bole. Food crops, on the other hand, need rich soil, must be well maintained, and should be kept free of competing vegetation. The work required to maintain the food crops in densely planted areas favoured the development of crowns on the okoume, which finally overshadowed the food crops. In lowdensity plantations (where trees were at a distance of 5 x 5 m or 6 x 6 m apart), the boles of planted trees became exposed over the years-a situation that leads to the growth of suckers and poor form due to the lack of natural pruning.
A good silviculture method for okoume, then, does not permit intercropping. Instead, spaces were set aside in the reforestation zones for food crop production, and cash crops were sought for long-term cultivation. In future, however, an agro-forestry method for okoume may be designed, using traditional food crops, so that people living in reforestation centres and neighbouring villages can grow their own food. Land left fallow will be used by the villagers after the growing cycle. This land will be interplanted with okoume, or prepared for natural regeneration if the presence of seed-bearing trees permits this.
Agro-forestry experiments aimed at cash crops have identified four crops whose essential requirements are known: cocoa, coffee, oil palm, and banana.
The search for practices that would reconcile the silvicultural management of okoume (which is characterized by difficulties in terms of pruning and the shape of the bole, sensitivity to changes in light, and requiring forest undergrowth between the rows of plants) with those of selected cash crops (which require as much light as possible and demand the supression of forest undergrowth during the first growth stage and the elimination of all competing growth during the second stage) is stymied by two technical problems: the distance between the okoume plants and the other crops; and the mode of transplantation for the okoume, given the differences in the natures of the species in question. Experiments were therefore conducted using different planting techniques: arrangement of seed spots, open planting, strip planting, and so on.
The most interesting results were obtained with the GrosMichel variety of banana. The production experiments yielded an average harvest of 10 t/ha during the first cycle, 25 to 30 months after planting. This is not high for a cash crop, but it is enough, given the extensive interplanting with okoume, since the object is to involve the population in agro-forestry activities.
Conclusion
In future, consideration must be given to transforming reforestation centres into rural development centres. Combining agro-forestry activities and wood-processing cottage industries, such centres would make more productive and rational use of the forest, as well as involving the local population economically. They would then be ready to be integrated into the life of the centres. It is also imperative that more thorough professional training be provided on the site for specialists (machine operators, assistant diesel mechanics, drivers, nursery personnel, and so on), for junior staff (supervisors, foremen), and for intermediate-level staff from technical schools who would spend periods on the site to augment their theoretical training.
This is the beginning of a process that will lead to the creation of private forests using plantations created by the villagers through agro-forestry methods. Experience to date shows that the forest cannot play an effective role unless the management objectives envisage real profits for the rural inhabitants. For this reason, development plans should be simple and well adapted to the environment. they should be designed in such a way as to allow the rural people to participate in their implementation and to derive maximum benefit from them.
Small processing industries in the villages will afford villagers access to semi-finished construction materials to improve their homes. A source of employment and income, they could become real centres of activity around which a multitude of related activities could arise.