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We have already suggested the paradox to be seen in the concurrent existence, on the one hand, of a rich indigenous agroforestry resource containing both a great variety of component trees and an extensive and sophisticated body of knowledge and, on the other hand, institutional proposals for the introduction and development of agroforestry. This incongruous situation is partly the result of the tendency of development specialists to promote the currently popular "solution', before the problem has been carefully investigated. It is also, as we have argued earlier, simply a lack of knowledge in institutional circles with regard to indigenous agroforestry. Even at the recent technical meeting on Pacific Island agroforestry held in Western
Samoa (Clements 1988), few of the speakers (mostly Pacific Islanders) appeared to recognize that in areas of shifting (swidden) cultivation the forest had any function other than fallow. The intricate, usually intentionally created, multi-purpose character of secondary forests described in this book received little attention - except for the discussion of Pohnpei's "agroforests" and an occasional mention of fruit or nut trees elsewhere.
As the combined pressures of population growth and cash cropping bring shortened fallows, declining soil fertility, and increasing cultivation on marginal lands to many of the Pacific's high islands, institutionally promoted systems such as contour hedging with Leucaena, Gliricidia, or Calliandra can help maintain soil fertility and lessen erosion, as has been clearly demonstrated elsewhere in the world. It should be recognized, however, that the process of replacing the indigenous agroforest with a few, usually exotic, species, useful though they are, is part of the pattern of simplification of subsistence systems in the Pacific (Ward 1986, 218) and loss of general biodiversity that is often seen as one of the great ecological threats of the present world. While the forces driving toward simplification and loss of natural forest and indigenous agroforest cannot be easily slowed, some interventions may help.
Appreciation of indigenous agroforestry
If indigenous agroforestry is to be encouraged, the character and value of the many existing agroforestry systems need to be more widely and deeply appreciated. As it is to that purpose that the material in this book is largely dedicated, we will only recapitulate a few of the worthwhile and significant technologies and characteristics that need to be kept in mind with regard to Pacific Island agroforestry.
The composite extended nature of
In the land-use strategy of Pacific Islanders almost all types of agricultural or wild lands are viewed as integral components of a larger agroforestry system. This view should be taken into consideration during development planning. Types of agricultural and wild lands found within the matrix of agroforestry systems include: native or secondary forest stands; sacred groves; monocultural woodlots, orchards, or coconut, cocoa, or oil-palm plantations; mixed tree- and ground-crop shifting agricultural plots; home gardens; and even small patches of grassland or adjacent mangrove or coastal forest.
Just as an entrepreneur wisely diversifies his assets, the Pacific agroforester diversifies his or her land use, both within individual plots or areas, or within the whole set of landholdings to which the agroforester or his or her extended family have usufruct, individualized, or even freehold (fee-simple) rights. Thus, any suggested changes or innovations to a given part of the system will affect the system's aggregate utility, stability, and sustainability.
Home gardens in agroforestry systems
Throughout the Pacific, home gardens are integral components of agroforestry strategies. They may exist as adjuncts to wider rural or village agroforestry systems, or stand on their own as urban home gardens. They are also among the most diversified and most dynamic agroforestry systems, often serving as both refugia for endangered or culturally-important traditional species, as well as avenues for the introduction and testing of new exotics. As suggested by Thaman (1988g), the promotion of urban and home gardening may be among the most cost-effective and culturally and ecologically appropriate means of satisfying many of the commonly stated objectives of national development plans.
High interspecies diversity
All traditional agroforestry systems, from the highlands of Papua New Guinea to the smallest atoll countries, are truly polycultural, exhibiting a high degree of interspecies diversity incorporating a wide range of cultivated, protected, and wild indigenous and exotic species. The numbers of species range from some 75 commonly encountered on atolls, which have among the poorest floras on earth, to over 300 widespread species found in the agroforestry systems of the larger islands of Fiji, Vanuatu, the Solomon Islands, and Papua New Guinea.
High intraspecies diversity
There is, additionally, a high degree of intraspecies diversity for most traditional tree and non-tree cultigens and for many recently-introduced cultigens. A wide range of named, locally-differentiable cultivars, varieties, or "land races" (Harlan 1975) exists for a given species. Within a given species, these cultivars have variable yield characteristics and seasonality, thus spreading yield distribution and seasonal surpluses more evenly. Different cultivars also have differential resistance to pests and diseases, tropical cyclone damage, salt water incursion and salt spray, and drought; differential ecological tolerance ranges in terms of adaptability to different soil types, shade, and hydrological regimes; and differential utility (for example, some coconut cultivars are used purely as drinking nuts, some for the flesh, and some for the large shells or the coir, which can be used for vessels or for cordage, respectively). As indicated in the case-studies, there is a particularly great range of cultivars of the traditional staple tree crops of coconut, breadfruit, pandanus, and banana and plantains; traditional perennial supplementary crops like sugar cane, sugar cane inflorescence (Saccharum edule), and hibiscus, or bush, spinach (Hibiscus manihot); traditional non-food plants, such as kava (Piper methysticum) and betel-nut (Areca catechu); recent introductions such as papaya, avocado, and a range of Citrus species; and many indigenous or, in some cases, possible aboriginally-introduced food and non-food species, such as Pandanus tectorius, Pometia pinnata, Hibiscus tiliaceus, Erythrina variegate, and a number of species of Ficus, which seem to have undergone systematic selection by the indigenous inhabitants of various islands and are now represented by a range of recognized cultivars or semi-domesticated genotypes.
Importance of wild food resources
Wild food resources are among the most important products of agroforestry systems, particularly in Melanesia, where extensive stands of primary and secondary forest remain. Most notable among these are a great diversity of wild yams, ferns, fungi, fruits, nuts and leaves and birds, frogs, snakes, grubs, insects, fin fish, eels, freshwater prawns, and other foods that are found within agroforestry zones. Even in grassland areas and on atolls, wild yams, ferns, wallabies, kangaroos, birds, edible plants, and crabs constitute important wild or emergency food resources. Apart from being nutritionally important, these wild products also constitute important low-capital-input, lowrisk seasonally abundant cash crops. When forests and trees are removed, however, in the process of agricultural intensification or replanted with exotic silvicultures, species diversity of wild plant and animal foods decreases significantly (Clarke 1965; Watling 1988), thus constituting a loss of food resources and cash and non-cash income.
Live fencing, hedges, animal pens, and
Of almost universal importance is the use of live fencing, hedges, and boundary markers, which serve as productive and ecologically valuable components of agroforestry systems. The use of trees or shrubs for such purposes includes: living fence posts for modern barbed-wire fencing on livestock development schemes or around crops susceptible to damage by livestock; boundary markers demarcating boundaries of land parcels belonging to different landholding groups, between the active gardens of individual gardeners, or between individual plots within a given gardener's active garden area; wind-breaks or barriers to protect coastal gardens from salt-laden air and resultant physiological drought and excessive salinity; and living animal pens, either with or without wire.
Integration of livestock and agroforestry
A common characteristic of most traditional agroforestry systems is an integration with, rather than a segregation or dissociation of, agroforestry from livestock husbandry. Domesticated pigs foraged in secondary forests and woodlands during the day and were also fed forest products to supplement their root-crop diet. Moreover, traditional systems often provided a means of storing surplus crop production for times of scarcity or feasting, such as in highland Papua New Guinea, where pig production served this purpose (Bayliss-Smith 1982). The increasing institutional emphasis on smallholder cattle projects, modern piggeries, and battery-raised poultry seems to be riddled with failure, compared to traditional foraging, waste-disposal, or tethering systems. Notable exceptions include cattle under coconuts, which seem to be far less productive than crops under coconuts (Schirmer 1983, 104), and cattle under timber trees. Evidence from throughout the Pacific shows that the modern intensive systems are extremely difficult to maintain, and in the case of smallholder commercial grazing systems, have caused widespread destruction of food crops and agrodeforestation (Grossman 1981).
Value of trees as staple crops
Throughout the Pacific, trees or tree-like crops constitute major or supplementary staples. The coconut, for example, is the major source of dietary energy on atolls, and in some coastal areas. Bananas and plantains, as a group, are perhaps the most important staples, after taro, cassava, and sweet potato, in terms of total calories provided to Pacific societies, with breadfruit being a particularly important seasonal staple in most areas. Other, lesswidespread or major seasonal staples include edible pandanus (Pandanus spp.), Tahitian chestnut (Inocarpus fagifer), and Barringtonia and Canarium spp. Such renewable (without replanting) energy resources are of particular impor tance, given that in parts of Melanesia, energy deficiency and not protein deficiency is the most serious nutritional problem and that increasing food dependency on imported white flour and rice, in both urban and rural areas, is a serious economic and nutritional problem (Coyne 1984; Hayward and Nakikus 1982; Jeffries 1979).
Trees as major sources of micronutrients
Along similar lines, fruit-trees, nut trees, leaf-providing trees such as Hibiscus manihot, Ficus spp., Gnetum gnemon, and Moringa oleifera, and sugar cane are some of the best sources known of vitamins, minerals, fibre, and other micronutrients, so vital to optimum health, but often lacking in modern urban diets. The increased consumption of such foods could significantly address increasingly widespread incidences of micronutrient deficiencies, such as anaemia and vitamin-A and vitamin B-complex deficiencies.
Medicinal importance of trees
The strategic importance of agroforestry systems as sources of the medicines used by many rural and urban people, most of whom have no access to or could not afford imported medicines, cannot be stressed too strongly. The importance of medicinal plants in agroforestry systems is underlined by the very high numbers of medicinal plants found in home gardens, in garden areas, and in protected forests or tree groves. Some two-thirds of medicinal plants are trees or shrubs (Thaman 1988g; 1989c).
Tree products of subsistence and commercial
In addition to foods and medicines, trees are the sources of a very wide range of construction and handicraft materials, cordage, dyes, poisons, scents, oils, decorations, and body ornamentation, and an almost endless range of utilitarian products of considerable subsistence and commercial value. Such products account for a significant proportion of real rural and poor-family urban incomes, incomes that are little affected by inflation or the vagaries of an unstable world economy.
Magico-religious and spiritual importance
The magico-religious or spiritual importance of trees, both in terms of sacred groves or individual living trees and the use of plant parts in magic or ceremonies, particularly in Melanesia, is an important aspect of Pacific Island agroforestry, and a reason for preserving trees. Ceremonial uses of plants include ceremonies or rituals associated with death, war and peace, human sacrifice and cannibalism, circumcision or coming of age, canoe making and launching, fishing, planting cycles, prayer sessions, as well as species serving as symbols or totems or planted in sacred groves or burial grounds and mediums for communicating with spirits or gods. Others are associated with times of revelry or are used in the production of baskets, mats, and other articles reserved for ceremonial exchange or dress. Many plants also feature prominently in Pacific Island mythology, legends, songs, riddles, proverbs, and cosmogony. As recorded in Ethnobotany of the Samoans (Setchell 1924), plant names were given to gods or vice versa, and songs and legends have developed around them and the "heroes, families, or villages, etc. they represent." One particular Samoan text of the "battle of trees and stones" enumerates between 70 and 80 tree names. Also very closely related to ceremony and ritual are magic and sorcery, which are still very strong in the Pacific, especially in Melanesia and parts of Micronesia. Plants are integral to such practices, which include magic related to love, exorcism of evil spirits, gardening, and death (Thaman 1989c).
Protection, pruning, and pollarding of
trees during garden preparation
Protection (not killing) of trees, although often with severe pruning or pollarding, in the preparation of new gardens, or when replanting old gardens, is a widespread practice that ensures the stability of agroforested landscapes. The ringbarking or removal of trees, often to allow for total tillage or ploughing, so commonly promoted to maximize the production of a single target crop, is a major factor in agrodeforestation. Not only does severe pruning or pollarding of valuable species such as Bischofia javanica, Hibiscus tiliaceus, and Macaranga spp., and fruit-trees such as mango, citrus, and Pometia pinnata, open up prospective garden areas to sunlight and provide additional organic material, and ash if gardens are burned, it also ensures renewed vigour of the regrowth and provides firewood and trellising for crops. Even ringbarking, if done in a particular way, will stimulate shooting from the base, thus not permanently eliminating a given tree from the garden area.
The practice of minimum or restricted tillage and the use of appropriate hand tools, which minimize soil degradation and favour the survival of trees, are universal and beneficial features of shifting agro forestry systems. It is especially important in the humid tropics and in steep terrain where heavy rainfall and high temperatures promote rapid leaching and oxidation and/or accelerated erosion of loosened soils. The practice of minimum tillage, where holes or mounds are prepared or the soil loosened only where plants are to be planted, is, thus, a positive, but labour-intensive, alternative to complete tillage or ploughing. Although appropriate in laboursurplus areas throughout the Pacific, the practice is being abandoned in areas such as Tonga and the Cook Islands, where ploughing and disc harrowing is encouraged in commercial monocultural production of root crops, vegetables, and fruits such as water melon and pineapple.
Mulching, composting, and fertilization
The use of leaves and other plant parts for mulching, composting, and fertilization in the cultivation of major staples and tree crops, particularly on atolls, is a well-developed practice that depends on the maintenance of a range of often minor non-food plant species found in agroforestry systems. In Melanesia, intensive mulching systems using the leaves of Pometia pinnata are employed in the East Sepik area of Papua New Guinea (Allen 1985), and a wide range of leaves are placed in planting holes of yams and taro or dug into the mud in irrigated taro gardens in Vanuatu, often to aid in insect or pest control, to enhance taste, or as part of diverse, but possibly functional, magicoreligious rites. Throughout the Pacific, various societies, such as the Koita in the arid savanna areas near Port Moresby, Papua New Guinea, deliberately mulch yam, cassava, taro, and sweet potato gardens with dried grass and other plant remains to reduce moisture loss and erosion and to improve soil fertility and yields. It is in Micronesia, in the harsh, almost soil-less atoll environment, that mulching systems are the most intensive. The most sophisticated systems are those used in the production of the ceremonially important giant swamp taro (Cyrtosperma chamissonis), with a wide range of leaves, some specially processed and dried, being mixed with scarce topsoil from under deliberately protected plants, and applied in woven pandanus or coconut frond baskets. Pulverized, rooted coconut logs, seaweed, pumice, and tin cans or rusting iron are also occasionally added to provide additional benefits, trace elements, or to alter the soil pH to free trace elements. The use of kitchen waste, animal manure, and ash is increasingly widespread in urban and home gardens, with mill-mud (waste from the sugar refining process) being used in some areas of Fiji (both on sugar-cane farms and in home gardens). Commercial inorganic fertilizers are only rarely, if ever, used in most existing agroforestry systems.
The practice of selective weeding to encourage culturally useful and important pioneer fallow species, particularly in the later stages of fallow, is a widespread characteristic of most agroforestry systems. Through such practices, fallow species and non-planted volunteer seedlings of other useful plants, such as mangos, papaya, citrus, and nut trees, can be selectively encouraged during the latter stages of the gardening cycle, thus hastening and controlling or managing the formation of productive tumbledown fallows and fallow forests or orchards, often including still productive stands of cassava, yams, taros, and bananas and plantains.
Permanent polycultural orchards
The establishment of permanent polycultural orchards, which often become mixed fallow forests, is a widespread practice. Such orchards, which may be almost entirely planted or may be mostly mature fallow forests in old gardening areas where useful trees had been planted, are protected as permanent productive features in the agroforestry landscape. The orchards can take the form of communal groves adjacent to villages or they can be individually-controlled groves in distant garden areas. The species composition varies from area to area, with a wide range of fruit, nut, and other useful trees represented, e.g. the Pandanus-breadfruit-Gnetum-Ficus wassa orchards described for the highland fringe of Papua New Guinea.
Planting, transplanting, or protection of
It is a widespread practice to plant, transplant, or protect indigenous species in agricultural areas and in urban and home gardens. Coastal strand species such as Barringtonia asiatica, Calophyllum inophyllum, Casuarina equisetifolia, and several others are often thus cared for, as are important food trees such as Canarium spp., Ficus spp., lnocarpus fagifer, and Pometia pinnata.
Domestication or semi-domestication of
Related to the deliberate planting of indigenous species was the domestication or semi-domestication of many of these same indigenous species. This was particularly the case in non-Austronesian areas of Melanesia (Kirch and Yen 1982; Yen 1976a; 1974). Included in this Pacific Island domestication were Burkella spp., Calophyllum inophyllum, Casuarina equisetifolia, Hibiscus tiliaceus, Nersosperma oppositifolium, Pipturus argenteus, and Pometia pinnata, which came to contain a range of cultivars or genotypes and were deliberately planted in gardens and for coastal stabilization.
Improved fallow systems based on deliberate planting of soil enhancing species was practiced in some areas, particularly in places in Papua New Guinea where agricultural intensification was far advanced. There, indigenous Casuarina spp. are deliberately planted as improved fallows and to provide fuel wood and fencing when cleared for the next garden. Albizia falcataria and Dodonaea viscosa are also planted to improve fallow in highland New Guinea. Guettarda speciosa and Tournefortia argentea are occasionally planted or encouraged to improve soils on atolls. A similar strategy has been adopted institutionally on Rarotonga in the Cook Islands, where Leucaena leucocephala, Albizia falcataria, Casuarina equisetifolia, and Eucalyptus spp. have been planted to rehabilitate degraded upland areas.
The productivity, sustainability, and adoptability of indigenous systems
The summary descriptions above of some technologies and characteristics of indigenous agroforestry systems serve to illustrate again the depth of knowledge and sophistication associated with the use of trees in the Pacific. The experts who understand, developed, and manage the systems - i.e. the local people - are already in place, "incountry," in the jargon of expatriate consultants. Formal experimentation and training might well improve the systems, but clearly, as noted in chapter 1, they possess already the criterion of adoptability, which, along with productivity and sustainability, is listed by Raintree (1990, 58) as one of the basic criteria possessed by any well designed agroforestry system. Similarly, that the systems are already local means that they meet the normative condition established by Bene et al. (1977); namely, that an agroforestry system be "compatible with the cultural patterns of the local population." As Raintree (1990, 92) says with regard to the introduction of agroforestry technologies, "there is little value in originality for its own sake" - espe cially when the local knowledge base is as immense as it is in the Pacific Islands. All of this suggests that encouraging local agroforestry systems would directly satisfy one of the currently most popular imperatives of development: community participation and concern with location-specific needs and opportunities (e . g., Chambers 1983).
Turning to Raintree's (1990) other two criteria, clearly the local systems possess adequate productivity or they would not have been maintained for so long. Indeed, archaeological and other evidence now supports the view that arboriculture has been practiced in the western Pacific for millennia (Yen 1990). Similarly, the systems possess sustainability and stability - even though they are dynamic - both in the sense that production has been maintained and that the environment has been protected if not enhanced. But being successful in the test of time does not mean that agroforestry systems achieve a high level of economic efficiency by modern measurements. The truth is of course that no matter how valuable the systems are believed to be, indisputable measurements are difficult to obtain. If we examine the anti-arboreal view of Künzel's composite Tongan farmer discussed at the beginning of this chapter, we can only agree that on a single field, planting or maintaining trees may lessen monocultural crop production. Yet the Tongan situation is unusual in the Pacific in that farmers hold individual tenure to single clearly demarcated fields, situated, on the main island of Tongatapu, in a favourable agricultural environment of mostly flat land with good volcanic soils. In more vulnerable areas of sloping land or poor soil, the protective and enhancing qualities of trees become more significant. Also, Pacific Island agroforestry systems have developed in a milieu where the unit of management was not a single field but a block of communal land wherein individuals held temporary tenure to various bits of garden land and enjoyed usufruct rights of varying sorts to trees, groves, and forest. This evershifting pattern of use amid a great diversity of arboreal and annual plants is antithetical to agronomic assessments of yield and economic efficiency. As Budowski (1982, 14) noted, comparisons of monocultures with agroforestry systems "may by no means be easy," especially as such evaluation is complicated by various short- and long-term economic projections concerning, for instance, the value of wood or the present and future estimations of environmental damage (for instance, erosion, use of pesticides in monocultures) and, even more so, by the appraisal of social and cultural factors, themselves complicated by a dynamic evolution in time that is difficult to foresee.
Because institutional agroforesters, agronomists, and development agents are generally preoccupied with commodity production and maximization of yields, they seem at times almost to suffer from a sort of paralysis in the face of the difficulties or impossibility of producing quantitative assessments of agroforestry systems, especially ones as complex and unbounded as those developed indigenously in the Pacific Islands. What is called for as interest shifts to "sustainable development" is new ways of evaluation that integrate protective and productive functions, and new land-use institutions that focus on optimization of the whole landscape rather than component maximization aims. Lundgren (1987) has put forth a similar line of argument, but, no more than he could, can we suggest an "ideal" structure and set of objectives for tomorrow's land-use-related institutions. We will, however, end with a few recommendations on how further to encourage agroforestry in the Pacific Islands.
Existing systems as prototypes for
Pre-packaged agroforestry technologies are by their nature alien, and their introduction is usually part of a short-term project, often set off from the general pattern of life and economy. When the project staff depart, the project often falls apart. Yet within the population already practicing indigenous agroforestry, experimentalists are legion. Pacific Islanders, like people all over the world, are fascinated by plants, like to experiment with them, and will happily carry a young individual plant from island to island or from valley bottom to mountain ridge or vice versa to establish it in a new home. If it works there, it will be reproduced and further disseminated. It makes sense, therefore, that at least some of the attempts at agroforestry intervention concentrate simply on supplying trees as raw materials for distribution. Some of these trees may be traditional, some newly introduced. The experimental work, the hybridization of new species into older systems, will be carried on in the place where it counts for most - among the local population. This does not of course mean that more formal agronomic experimentation is not equally or more valuable in terms of accurate information, but simply that experimenta tion carried on locally in the forests, woodland fallows, gardens, and grasslands is likely to be much more effective in achieving the goal of encouraging agroforestry.
Nurseries already successfully distribute seedlings and cuttings of fruit-trees, timber species, and legume trees in some Pacific Island countries (e.g., in Tonga, as described by Künzel 1989, 47-48), but they could be more comprehensively stocked and could incorporate extension work on agroforestry more strongly. Such nurseries would provide a central, permanent focus for agroforestry development.
Few Pacific Island countries would be able to establish an "agroforestry unit" on a permanent basis. If they were, the unit might better be placed in the Department of Agriculture rather than the Department of Forestry. In place of such an intersectoral unit, extension workers could at least be better educated in agroforestry and in ideas about the broad integration of protection and production. They could, for instance, stress the values of durable living fences or hedges; promote traditional techniques of mulching, composting, or improved fallow; and encourage agroforested home gardens and polycultural orchards.
As with extension education, so too could agroforestry be promoted and publicized by other forms of education. Multimedia public programmes could be developed, in the vernacular, to stress the long-term value of existing agroforestry systems and the dangers of deforestation and agrodeforestation. Radio programmes along these lines already exist, as in Vanuatu, where the Environment Section has a weekly broadcast. Agroforestry can be better introduced, with appropriate field activities, into school curricula in both urban and rural areas. The nutritional value of tree foods can be incorporated into formal education or, for instance, into child-care information, as has been done by Fiji's National Food and Nutrition Committee.
Environmental impact assessment
When forests and woodlands are to be cleared, EIA generally includes a consideration of consequences with regard to erosion or hydrology, but the lost value of food and other products from trees also needs to be part of the formal assessment procedure. That this value often exceeds the value of the timber has been clearly demonstrated elsewhere in the world.
Although long-term intensification can be seen as destructive of forests, intensification of annual production, often through the use of agroforestry techniques (Raintree and Warner 1986), lessens the extension of agriculture in the short term. Experience has shown, in Java, for instance, that severe agricultural intensification leads to a highly intensive, though spatially restricted, agroforestry. Inducing farmers to intensify is another matter, for it generally requires greater inputs, in some form such as capital, labour, fertilizers, management skills, and so forth. Appropriate consideration of the effects on the whole landscape of the intensification of certain kinds of production from land again requires that sectoral compartmentalization be lessened.
Further research and documentation of
Individual countries need to establish intersectoral committees or working groups to compile and publish lists and descriptions of useful tree species that should be protected or promoted locally. Further research is required into the existing systems, their component trees, the associated technologies, the methods of establishment, and the quantity and value of the products.
This book's descriptions of indigenous Pacific Island agroforestry systems may at times have seemed excessively detailed, but the book's coverage of the topic remains far from complete. What has been described, however, is sufficient to establish that traditional and existing agroforestry systems and their component trees have played and could continue to play a significant role in the provision of useful materials, in the enhancement of productivity and diversity, and in the stability of agro-ecosystems in the Pacific Islands. Recognition of agroforestry's multiple values and further documentation of indigenous systems can contribute to the effort to stem agrodeforestation and to stimulate the future flowering of Pacific Island agroforestry on the basis of the rich indigenous resource that has already for so long successfully blended production with protection.
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