Tropical forests are best known for the wide variety of plants that grow in them. Small tracts of forest may contain hundreds of plant species; neighboring tracts may exhibit similar levels of floristic diversity, but the species are different. Given such a large assortment, it is not surprising that many of these plants have properties that have proven useful to human beings. Certain trees are good for boards or making canoes or framing houses. Some trees produce delicious fruit, aromatic spices, caffeine-rich leaves, or a valuable latex or resin.1 The leaves of many palm species are used for thatch, while other species produce edible fruits or floral nectars that can be distilled into wine. The stem fibers from one group, the rattans, form the basis of a multibillion-dollar furniture industry.2 Tropical forests contain plants that are used for medicine, plants that are used as contraceptives, and plants that are used as intoxicants. All these botanical resources have been used by indigenous communities for thousands of years. The main reason we know as much as we do about the uses of tropical plants is that forest dwellers have explained them to us.
Interactions between communities and tropical forests are not always positive, however. Resources can be overexploited or destructively harvested; small tracts of forest can be cut and burned for agriculture. These occurrences become more prevalent as population density and market involvement increase. More families need more land to grow food, and growing markets demand more timber, more fruit, or more rattan, regardless, it seems, of ecological impact. The general perception by many in the international conservation community holds that the best way to ensure the preservation of tropical forests is to get the people out of them. Stop the harvest of forest products, gazette more protected areas, hire more forest guards. The growing appreciation of the importance of tropical forests in ameliorating impending climate change seems to have strengthened the global mandate to separate the people from the forest.
While an extensive network of protected areas clearly has value for the conservation of biodiversity in the tropics, it is not the only way to approach the problem.3 It is important to remember that the constant manipulation of tropical forests by human beings over time has created and shaped the plant communities that are currently being designated as parks and reserves. In many cases, human activity has actually increased the diversity in tropical forests by creating new habitats, selective weeding, and the introduction of new species. Once these human activities are constrained or eliminated, the floristic composition of the forest will surely change—and we might not like the result.
In addition, the exploitation of plant resources in tropical forests need not inevitably lead to resource depletion and forest degradation. Resource depletion happens only when the amount of plant material harvested exceeds the amount that the forest can reliably produce each year. This is the basic premise of sustainable resource management. If we know the existing stock of the resource and can obtain estimates—even crude estimates—of its yield each year (how much timber or resin or palm thatch is produced), we can estimate a sustainable level of harvest for the species. If, and this is a big if, harvest levels are respected and the community consistently collects less than the annual growth of the resource each year, that resource can be exploited year after year with minimal impact on the plant population that produces it.
The difficulty comes in trying to conduct the inventories to quantify the stocks of different species and in setting up the yield studies to estimate how much of a given resource the forest produces each year. This work has to be done in close collaboration with local communities so that they will learn how to collect the necessary data themselves, can appreciate how the data fit together to define a sustainable level of exploitation, and, most important, will develop the motivation to control how much they harvest each year. The temptation to depart from the onerous prescriptions of a forest management plan is ever present, especially in times of financial hardship or when market prices soar.
For the past thirty years, I have been involved in a variety of projects focused on the conservation and sustainable use of tropical forests by local communities. Some of the projects were successful; most provided valuable data and training in resource management; and a few turned out to be no more than temporary distractions from more critical issues a community was facing. The results from each of these investigations, however, can teach us something important about the current realities of resource use in the tropics.
Several factors motivated me to write a book about these field experiences. First, I have learned intimate details about the ecology, use, and management of a number of little-known yet potentially valuable tropical forest resources and am convinced that these data could be put to good use by resource managers. In addition, the participatory protocols that were developed for managing wild populations of tropical plants offer valuable alternatives to deforestation. It is possible, and not overly difficult, to use tropical forests in a way that both conserves the forest and provides local communities with an incentive for forest stewardship. There is an attractive logic associated with helping communities develop sustainable management systems for their forests, rather than excluding them from decisions that directly affect them or paying them to leave the forest alone.
Location of projects I have been involved with that focus on the sustainable use of tropical forest resources by local communities. The numbers refer to the relevant chapter in this book; the dates of fieldwork are included on the first page of each chapter, and geographic coordinates of specific localities are also provided where applicable.
I have had the good fortune to work with forest-dwelling communities in Asia, Central and South America, and Africa, attempting to do, more or less, the same type of project with various resources, ethnic groups, and forest types. Such a replication of field methods across so many different contexts is rare, and I thought it worthwhile to bring all the projects together—the successful ones, as well as the less successful—for comparison. Many of the experiences I have collected during my fieldwork are at odds with some of the things people usually hear about tropical forests. For instance, none of the forests that I worked in, even in the most remote locations in Amazonia, Borneo, and Papua New Guinea, were “pristine” or untouched. Local communities had been living in these forests, farming, planting trees, and managing the vegetation, for centuries. But to learn what indigenous peoples have done, we have to ask them because the imprints of their management activities are, in many cases, essentially invisible—something that for me constitutes one of the hallmarks of successful silvicultural treatment.
I have published many scientific papers about this work, but the present offering is not a scientific monograph. Each chapter, or case study, offers a narrative that illustrates different aspects of a particular forest resource, community group, and interaction between people and plants. The stories illustrate the ecological conditions or social contexts I encountered when I started my work, describe the intervention or data collection process I facilitated, and help me summarize the results.
The level of detail provided, much like my field notes and recollections, varies from chapter to chapter depending on the place, my skill with the local language, and (though I hate to admit it) how long ago I did the work. (The chapters are ordered chronologically.) Some of these stories offer snapshots of ecological understanding, careful resource use, and indigenous silviculture; a few describe difficult situations in which neither the people nor the plants seem to be thriving. It is my hope that these stories will help future researchers find more effective and equitable strategies for the long-term conservation of tropical forests. All the projects, in hindsight, have involved delightful people, lots of laughter, long conversations about plants, and mostly fruitful if largely unexpected outcomes. And this, perhaps, is what I would most like to share with the reader—the reward of thirty years of concerted trial and error.