Wholesale go-between traders c
Wholesale urban trader
-H Rural gatherers 4
Fig. 9.2. Trade in medicinal plants (adapted from Falconer et al., 1992: 140-1).
With the extensive and wide ranging use of medicinal plants and developed trading links both regionally and to urban markets, does this use lead to overexploitation? There appears to be mixed evidence as to whether medicinal plants are becoming more scarce in Ghana. The case studies reviewed give conflicting impressions. For example, Falconer et al. (1992) report that the majority of people interviewed in rural areas do not believe that the supply of plant medicines is dwindling. Many traditional healers believe that medicinal plants are god-given, and that thus their supply is eternal; however, some are less optimistic and feel the forest reserves should be well maintained to safeguard forest medicines. The most widely used plants were found in fallow bush areas. Many people did suggest that herb gardens be established near villages for easier access. Wondergem et al. (1989) report that although plant medicines were generally available, there was a marked decline in habitat and also decreasing numbers of herbalists. IUCN (1988) remark that Garcinia kola, the false kola, is becoming rare as a result of overexploitation for use as chewsticks. It seems likely that as areas of unmanaged forest are diminishing, and farm fallows decreasing in length, then certain plants will become more scarce.
The evidence from other countries (for example, Cunningham (1991) in South Africa, and Joshi and Edington (1990) in Nepal) would indicate that increased marketing and commercialisation, especially in response to demand from urban areas, is likely to lead to overexploitation of certain species. In Nigeria, Osemeobo (1992) blames overexploitation on urban markets for medicinal plants, and distinguishes plant utilisation according to the location of traditional medical practitioners. Osemeobo argues that the way in which plants are exploited and their sources varies between practitioners who are based in villages and small rural settlements, in semi-urban areas, or in urban areas. In villages, medicinal practitioners harvest plant materials from the local environment in ways that ensure a sustainable supply. In semi-urban situations medical practitioners utilise some plants collected locally, purchase some from markets, and may also cultivate others. In these circumstances, a few species are endangered, but artificial regeneration guarantees their maintenance. In the urban areas the major source of plant materials is from markets, and few practitioners cultivate herbs either for commercial or domestic use. Under these circumstances, overexploitation is likely as the practitioners are not responsible for conserving plants in their habitat.
Plants may be overexploited as a result of economic policy and market failures (Swanson, 1992), but physiological features will make some kinds of plants more vulnerable to overexploitation. In South Africa, Cunningham (1991) identifies two causes of overexploitation of medicinal plants. First, a dramatic decrease in the area of indigenous vegetation as a result of the expansion of agriculture, afforestation and urban development as the major factor. Second, a rapid increase in those who use medicinal plants, and a corresponding increase in demand for herbal medicines contributes to this trend. Scarce, slow-growing forest species are particularly vulnerable to overexploitation. In the South African case, where commercial trade predominates, this overexploitation has resulted in a rapid increase in the prices of species that have been depleted in the wild. Cunningham comments that the social consequences of this overexploitation are first felt by the poorest sectors of the community as they have to walk further or pay more for medicinal plants.
The degree of disturbance to the species population, and vulnerability to overexploitation, depend on demand, supply, the part used and life form. Cunningham (1991) uses life form categories to represent a useful classification for establishing resource management principles. Life form categories represent a natural sequence from phanerophytes (forest trees), through chamaephytes (shrubs) and hemi-cryptophytes (perennial herbs and grasses) to therophytes (annuals). Forest trees represent the most vulnerable category because of preferential exploitation of the thick bark from large (old) plants which have a long period to reproductive maturity, a low ratio of production to biomass, and specialised habitat requirements.
As shown in the previous section, different parts of the plants are used for medicines. These include bark, root, bulb, whole plant, leaves, stems, fruits and sap. The category identified as being of greatest concern to herbalists is that of the slow-growing, popular species with a restricted distribution which are exploited for bark, roots, root tubers, bulb/corms or where the whole plant is removed (Cunningham, 1991). Coppicing ability and the vulnerability of trees to bark removal are also important attributes which vary with the physiology of different species. Oldfield (1984) observes that those plants most vulnerable to extinction are naturally rare and which must be destroyed to yield the desired products, yet are long lived, slow maturing and difficult to cultivate or domesticate; therefore it is a mixture of economic, policy and physiological factors that will determine the vulnerability of a plant to overexploitation.
At present there is little evidence for the overexploitation of species of medicinal plants in Ghana. Perceptions of scarcity are mixed in the survey reported in Falconer et al. (1992). We could postulate, however, that the circumstances and characteristics which tend to result in overexploitation (slow growing species, conflicts over property rights, growing urban demand) do exist and that this would need to be addressed in prescriptive measures.
Cultural values and conservation Property rights play a particularly important role in determining the exploitation of medicinal plants and the conservation of their habitat. This is especially true in the case of traditionally determined rights to particular protected areas in the form of sacred groves. Local institutions in the sense of social control, customs and mores concerning access and rights to extraction, may constitute sophisticated conservation strategies. The incidence of sacred groves, for example, in many countries in Africa, India and North America, and in Europe in the past, ensure that areas of forest are preserved. These groves are often found to be in areas where they protect water-sheds, or areas likely to be subject to severe erosion, or which have specialised ecological functions. They often contain rare or special species. The set of rules governing these areas may allow for their limited exploitation; by particular people from the community (priests, herbalists, healers), or only at certain times of the year (holy days, feast days). These practices have sometimes been described as 'backward' or 'witchcraft' by colonial administrations or governments; their cultural, ritual and environmental, even economic significance, were not recognised, and were actively discouraged or even outlawed.
In many parts of West Africa, for example, forest areas and specific trees are protected and valued for particular cultural occasions and as historic symbols. Each community has its own traditions associated with sacred areas, and as a result the species found in them vary greatly. Sacred groves are the site of ritual and secret society initiations, and where social and political values, morals, secrets and laws are passed on to young people (Falconer, 1990). These areas often house religious and ritual relics and may be ancestral sites or where people can communicate with their ancestors. The groves are often the site for ritual healings and the location where medicinal plants can be found.
Dorm-Adzobu et al. (1991) describe how, for nearly three centuries, the community of Malshegu in the northern region of Ghana have preserved a small forest they believe houses a local spirit, the Kpalevorgu god. Access to and utilisation of plants and other resources in the grove are strictly controlled, as described in Box 9.3. When it was first demarcated, unwritten regulations were put in place by the fetish priest and other village leaders regarding land use in and around the grove, and over time these rules have been amended to ensure their continued relevance and affectiveness. Dorm-Adzobu et al. contend that this sacred grove may represent one of the few remaining areas of closed-canopy forest in Ghana's northern savanna zone. The grove therefore constitutes a critical habitat for the fauna and flora of the area, as well as serving important environmental and social functions for the people of Malshegu. The grove is an important source of both seeds and seed dispersers vital to shifting cultivation practices, and of herbs for local medicinal and religious practices.
Box 9.3: The Malshegu sacred grove in Northern Ghana (from Dorm-Adzobu et al, 1991)
All forms of farming and grazing in the sacred grove and the fetish lands (the area surrounding it) are prohibited. Entrance into the sacred grove and fetish land is only permitted during the biannual ritual honouring Kpalevorgu, the community god, or on other special occasions with the advance consent of the Kpalna and other village leaders. The Kpalna is an important community religious leader and priest, who is the principal advisor to villagers on spiritual matters, and also the primary traditional healer and provider of traditional medicines, including plants and other healing items, for the community. During these festivals, some hunting and collection of forest resources such as birds and small animals, and the branches of certain trees which are carved for tool handles, is also allowed. Only the Kpalna and his aides have regular access to the grove and fetish lands where they pray to the Kpalevorgu god on the community's behalf, and also collect medicinal plants as needed for the community.
The religious leader, the Kpalna, is shown to play an important role in the preservation of Malshegu's sacred grove. This is as a result of the complex roles that these figures play, and the linking of the spirit and natural worlds. Fink (1990) describes how the herbalist has a place in Dormaa religion as one who knows the souls of the plants and animals, and of the deities and spiritual beings that dwell in nature. These plants and animals therefore need to be treated with respect and reverence. For example, when a herbalist picks a plant he or she will make a sacrifice to the soul or spirit which may dwell in it. This is to prevent the spiritual forces from turning against the herbalists and his or her patients by withholding the plants' curative powers (for example, Wilbert (1987) describes the practices of female Warao herbalists).
Traditional societies have evolved novel ways of 'plant tenure' (Juma, 1989: 232; Fortmann and Bruce, 1988) which in most societies pre-dates land tenure. Trees may have important symbolic roles. In many societies, trees represent a maternal symbol, as protector and provider of many products, including food, medicines and shelter, and protecting against evil spirits. Trees may symbolise fecundity; they may also be a phallic and paternal symbol. Falconer (1990) explains how forest trees, the links between the sky and the earth, often symbolise links between the spiritual world of ancestors and people. They may also symbolise a mediator or judge.
The rules governing use and the adherence to practice, however, varies considerably between communities, even within the same region, which makes it very difficult to formulate a policy on the basis of such cultural values. We can now examine the policy prescriptions which would encourage sustainable utilisation of medicinal plants and conservation of the natural habitat.
Was this article helpful?
Achieve the Fitness and Wellness for You that you have always wanted by learning the facts so you can take the right steps to maximize your health. Learn How to Achieve Real Fitness and Wellness for a Healthy Body, Mind and Spirit to Improve Your Quality of Life in Today's World. Receive Valuable Information to Discover What Really Matters and What Actually Works in Finding Genuine Wholeness for All Aspects of Your Being.