Editorial The
evolution of agroforestry systems In many parts of the world, traditional landuse systems came under pressure as the local population grew rapidly. On the fragile soils of the tropics, it became impossible to practice traditional shifting cultivation because the pressures for land were too great and the tree fallows, which allowed the soil to recover their fertility, had to be shortened. This was the start of a downward spiral of land degradation, which eventually gave birth to modern agroforestry around the middle of the twentieth century. In many areas of the tropics, professional foresters – like my father – together with agriculturalists, started to recommend in the 1940s that trees should be planted along the contour to reduce erosion and to conserve the soil. The agroforestry bandwagon started to roll. It was quickly recognized that there were numerous niches within the farm where trees could be planted both to provide products like fuelwood and fodder, which were becoming scarce, and to return organic matter and nutrients to the soil. From these developments, agroforestry was defined as “a collective name for land-use systems and practices in which woody perennials are deliberately integrated with crops and/or animals on the same land management unit, in a spatial mixture or temporal sequence” (ICRAF 1993). Today we have agroforesters in almost every country doing research, publishing scientific papers in specialist journals, writing textbooks, lecturing to students, and helping farmers to implement numerous agroforestry systems. Agroforestry has become a multidisciplinary science. Before any of these developments, farmers in some remote corners of Asia, notably Sumatra, and to a lesser extent parts of Africa and Latin America, were experimenting with ways of making fallows commercially viable by enriching them with trees that produce marketable products. In doing this they created agroforests which are biologically diverse and economically profitable: a marriage between production and conservation that we have only recently begun to appreciate as being a potential model for wider application. These agroforests are grounded in ethnobotanical knowledge, as well as in an indigenous appreciation of ecology. In a departure from the rather agronomic approach to agroforestry that developed in the 1960s to 1980s, I published in 1996 a new vision that is based on the realization, in part stimulated by seeing the Sumatran agroforests, that agroforestry is in effect applied ecology (Leakey 1996). This ecological vision sees that the different stand-alone agroforestry systems can be integrated within a given area as components and stages of an agroecological succession, akin to those of natural ecosystems, ending up as productive climax agroforests. Furthermore, this view of agroforestry also allows the appreciation that, on a landscape scale, an agroecosystem is made up of a mosaic of areas at different stages in the succession and does not exclude the possibility that some of these may be patches of monoculture. A new definition of agroforestry, accepted by ICRAF (International Centre for Research in Agroforestry), is therefore: “a dynamic, ecologically-based natural resource management system that, through the integration of trees in farms and in the landscape, diversifies and sustains smallholder production for increased social, economic and environmental benefits for land users at all levels” (ICRAF 1997). Another recent departure from the old agronomic vision of agroforestry is the initiative to domesticate what I have called the “Cinderella” species, which have been overlooked by the Green Revolution and to a large extent by science in general. There is a host of plant species that indigenous peoples have collected and used from natural forests and woodlands that are never planted and are increasingly threatened by habitat destruction. These species are ideal for agroforestry as they are adapted to the region, well known by local people and often present in local and regional markets. With the help of local farmers, a program coordinated by ICRAF has identified the priority species for domestication in both the humid and semi-arid lowlands of West Africa, the Miombo woodlands of the southern Africa plateau, and western Amazonia. Germplasm collection and conservation has been done for dika nut, marula, masuku, African mesquite, baobab, shea tree, mulateiro, bolaina blanca, peach palm and sesban. Other collections already exist for African plum and the peach palm. The next stage of involving farmers in the identification of superior individual trees for multiplication as cultivars is beginning for African plum, dika nut and peach palm. Village nurseries will be established so that the farmers in participating villages are the custodians of the cultivars developed from their farms. In this way it is hoped that they can then benefit from their multiplication and dissemination.
In the Viewpoints and Issues section, we
highlight the success story of “more people, less
erosion” from Machakos in Kenya, which shows that
rapid population growth can give rise to environmental
recovery, rather than an inevitable increase in poverty
and natural resource degradation. Machakos is an area on
the edge of the semi-arid zone, which in the 1930s had a
severe environmental problem, and today has a greatly
increased human population, with increased farm outputs,
a diversified economy and a rise in the numbers of trees
in the landscape. Similar examples are found elsewhere in
Kenya and in Tanzania.
Readers of the Handbook may not know the promising economic plants that Roger Leakey refers to as “Cinderella species”. Here is a glossary of some of the species mentioned in his editorial, with notes from publications cited in the Economic Botany Bibliographic Database (EBBD). The EBBD – compiled by the Centre for Economic Botany at Kew – is a database of key-worded literature references relating to useful plants (excluding major crop species) from around the world. /GJM African mesquite (Prosopis
africana (Guill. & Perr.) Taub., Fabaceae). Prosopis
is a genus of spiny trees and shrubs that are common in
some agroforestry systems of dry zones. Although most
species are found in the New World, P. africana
is widely distributed in the Sahel region of Africa,
where various parts of the plant are used as condiment,
fish poison, food, forage, fuel and medicine. Mulateiro (Calycophyllum
spruceanum (Benth.) Hook f. ex Schumann, Rubiaceae).
A native of the Amazon, this tree – which is easily
propagated and grows to a height of 30 meters – is
also known as capirona or pau mulato in Brazil. It is
best known as a valuable, dense and beautiful tropical
timber. A popular medicinal plant, its bark is used to
treat fungal skin infections and intestinal parasites.
Cultivating Trees The People and Plants Handbook is a source of information on applying ethnobotany to conservation and community development. It is designed for people who work in the field, including park managers, foresters, students, researchers, cultural promoters, and members of non-governmental, governmental and indigenous organizations. The first four issues in English are now out of print, but are available on People and Plants Online, http://www.kew.org.uk/peopleplants Spanish editions of the first three issues, under the name of Cuadernos de Pueblos y Plantas, are available in hard copy, and will be put online in 1999. Please send us suggestions of new subjects that could appear in future issues. We would appreciate receiving any pamphlets, posters, popular articles, drawings or other materials that illustrate the objectives and results of programs and projects in which readers of the Handbook are involved. If you wish to reference this issue of the Handbook, we suggest the following citation: Martin, G.J., A.L. Agama and R.R.B. Leakey, editors. 1999. Issue 5. Cultivating Trees: The Evolution of Agroforestry Systems. In G.J. Martin, general editor, People and Plants Handbook: Sources for Applying Ethnobotany to Conservation and Community Development. Paris, UNESCO. When writing to individuals cited in this issue, please tell them you ‘saw it in the People and Plants Handbook’. Letting them know where you found information about their organization, publication or project will help us strengthen our networking efforts.
Leaves of paper: letters to the editors 25 March 1999 My experience in a lowland rainforest area in northwest Papua New Guinea suggests that fallows are the primary areas of human use and that gardens have an auxiliary function in local subsistence. In the community of Krisa, a mixture of subsistence practices is employed, including hunting and gathering, swidden gardening and the nurture and cultivation of trees. The latter appears to be the most characteristic feature of the subsistence system and yields foods as well as medicines and working materials. In contrast, gardening proceeds on a small scale, and it yields supplementary foods rather than staples. Individuals or families may well do without the preparation of any swidden plots for years. The main function of gardening appears to be the propagation of useful trees, rather than the immediate and direct provision of crops. Consequently, a host of useful trees are found in fallows (excluding the sago palm that is confined to swampy areas). The situation in Krisa possibly constitutes an extreme example of tree cultivation and fallow use, yet it might draw attention to similar instances.
18 April 1999 My concern about agroforestry is that, despite all the academic interest that has been shown in recent decades, it remains one the world’s best – and best kept – secrets. Take the example of the West African Sahel, where rural people are among the poorest in the world. Here, a traditional agroforestry system known as the ‘parklands’, in which valuable trees are left scattered in cropland, has been functioning beautifully for centuries. It is now breaking down under the combined pressures of population, need for land, over-grazing and desertification. There is also constant pressure applied to farmers – usually from outside – to produce cash crops in monocultural systems following the doctrine of the so-called Green Revolution that runs counter to environmental good sense. In the Sahel, one has the impression that only the farmers themselves – and a handful of agroforestry researchers – even recognize the value of the indigenous trees or the agroforestry approach to land use. ICRAF researchers and their national partners in Mali recently showed that products from a single tree species, Parkia biglobosa, can double a family’s annual income. And yet politicians ignore this knowledge. It doesn’t take a Nobel scientist to figure out that there is something amiss, that a huge information and cultural divide still separate researchers from land users. This must be bridged, and quickly. Agroforestry research results have been hidden away far too long in annual reports and scientific journals that never see the light of a farmer’s day. These results have be let out, passed on in a useful and informative way to those who need them most – policy-makers, development and extension agents, and farmers themselves. I sincerely hope that your publication is just the first of many such efforts to break the silence, bridge that information gap and let the world in on the as yet unrealized potential of Cinderella trees, their value in agroforestry systems and their value to the world’s consumers.
28 April 1999 After working predominantly in Latin America, I do not have the perception that modern agroforestry began with the problems of shifting cultivation. There is a general tendency amongst many agroforesters to ignore what I would claim is the most successful agroforestry system in the world and what it can teach us for the development of new systems. I refer to the combination of shade trees with perennial crops, such as coffee, cocoa and other plantation crops. These agroforestry systems have been used by large and small landowners, and rich and poor farmers for over 100 years in many parts of the humid tropics. They are critically important for protecting soils and biodiversity, and they contribute to ecological and economic sustainability for the practicing farmers. They vary from simple combinations of one shade tree intensively managed for one crop variety to highly complex mixtures of over 100 shade trees over a mixture of different varieties of coffee, cocoa and other crops. These systems do not necessarily develop into a climax agroforest, akin to a climax natural succession. The management of a particular coffee or cocoa plantation can vary from effective abandonment, which increases diversity, to intensive management when coffee or cocoa prices are high, which may include a reduction in the degree of shading, and then reversion to abandonment when prices drop.
19 May 1999 We believe the best method for the development of improved agroforestry systems in the tropics is through a participative approach to research, in which local communities and research institutions work together from the start. ICRAF works with national partners and local communities to determine which tree species are priorities to farmers for research and development. They focus on species that can be planted to increase economic and nutritional security, as well as contribute to improved natural resource management.
It also indicated a trend toward the collection of germplasm from cultivated forest areas, rather than natural stands. This raises the possibility of potential genetic bottlenecks during the regeneration of germplasm, if material in cultivated forest areas originally came from only a few trees. Based on this information, collections of germplasm from key species in the region have begun, in particular of Guazuma crinata and Calycophyllum spruceanum, fast-growing timber tree species; Inga edulis, an important fruit tree that is also used to improve soil fertility; and Bactris gasipaes, an important source of fruit, wood and heart of palm. During collection, indigenous knowledge of farmers is employed to select superior trees. Farmers participate fully in the collection process, while trials to identify superior germplasm are established on-farm and are evaluated jointly by farmers and scientists. Farmers participating in trials benefit directly through the production of saleable products such as timber and fruit, while the wider community benefits on a long-term time scale through the identification of superior trees that can be disseminated to them for cultivation. We believe that a similar participative model of research can be applied by others to obtain beneficial results, in the minimum possible time frame, for poor farming communities in the tropics.
5 May 1999 We have a coffee farm of 50 hectares, more or less,
located in the 61,500-hectare Moleta-Manupali Critical
Watershed in Lantapan, Bukidnon, a province in the island
of Mindanao, in the southern part of the Philippines. A
couple of years back my family made the decision to
convert this and another farm back into a tropical rain
forest, starting with the collection and planting of
seedlings of rare and endangered indigenous Philippine
hardwood trees. At present we are conducting a resource inventory of the different tree species found in a 10-hectare forest on our property in coordination with the College of Forestry of the Central Mindanao University. As soon this is completed, we intend to conduct another resource inventory, this time with the help of Mr. Saway’s people, to determine which of the species have uses other than for timber. We recently entered into an agreement with the Ecosystems Research and Development Bureau (ERDB) of the Department of the Environment and Natural Resources to provide assistance in collecting seeds and seedlings of the species that interest us and training of our farm personnel in clonal propagation of dipterocarps and other trees. With the assistance of agroforestry experts, we would like to use what information we can gather to develop a working Philippine model for agroforestry and probably ecotourism, consistent with sustainable development and biodiversity conservation, which we hope will also be economically viable.
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