"Forest exploitation" in the minds of many people is often associated with the tropical timber trade. However, other non-wood forest products (NWFPs) such as medicinal plants, now provide the opportunity for a more seemingly benign form of forest exploitation that is also extremely profitable. Many laboratories throughout the world are currently studying the action and biochemical composition of African plants and recent scientific studies on the activity and toxicity of traditional medicines have shown a number of local medicinal plants are as efficient as the "Western" prescription medicine imported by many developing countries.
Undoubtedly, African medicinal plants can contribute to conservation and development through sustainable use in both in-situ and ex-situ situations, and if the appropriate legislation regarding the exploitation and management of medicinal plants is adhered to. Plantecam has for several years aimed at the conservation of Cameroonian medicinal plants through cultivation, as well as educating local communities in the management of the resource in the wild.
Key words: Medicinal plants, exploitation, Cameroon
This paper will focused on three main areas of activity:
· The framework of research and identification;
· Harvesting and marketing;
· A discussion of the actions that have been taken by Plantecam to ensure the sustainable management of Prunus africana and other medicinal plants
The framework of research
Information on plants is obtained through extensive ethnobotanical surveys undertaken by Plantecam, supplemented through the perusal of existing literature, especially traditional pharmacopoeia. A wide variety of use categories are studied, for example:
· Plants with known veterinary uses (Tephrosia vogelii, Swartzia madagascariensis);
· Cosmetology (Carapa procera, Alöe spp., Calophyllum inophyllum, Myrianthus spp., Pentadesma macrophylla, Allanblackia spp.);
· Dietetic (Adansonia digitata, Carica papaya);
· Herbal (Chrysanthellum americanum, Euphorbia hirta, Desmodium adscendens);
· Pharmacological (Prunus africana, Pausinystalia johimbe, Strophantus gratus, Tabernanthe iboga, Fagara macrophylla, Phyostigma venenosum).
Identification
Once the uses of species are established during the ethnobotanical surveys, authoritative identification is necessary. Voucher specimens are collected and through the use of keys and previously identified species, are then named. The determination of plant names allows further collection and development of the resource with the confidence that the same species previously shown to be useful can be recognised and re-collected.
Index cards
For each plant, an index card is completed and is composed of the following information: phenology, taxonomy, natural distribution, morphology, life form, the possibility of domestication and the estimated accessible potential wild resource.
Plantecam harvests and trades in large quantities of a number of medicinal plants. These include the following species:
· Prunus africana (for the treatment of benign prostate hyperplasia);
· Pausinystalia johimbe (as a remedy for male organic impotence);
· Voacanga africana (a hyper-tensive);
· Strophantus gratus (heart tonic);
· Physostigma venenosum (for use in ophthalmology).
Medicinal plant harvesting is controlled by the preliminary obtention of an exploitation license of forest species; the prerequisites or qualifications are described in the Forest, Faunal and Fisheries Regime (Law No 94/01 of January 20th, 1994) and in the directions of use of this regime (Decree No 94/436 of August, 23rd 1994). The delivery of this license is accompanied with a report book describing clearly the harvesting practices according to the vegetative structure to be extracted. Plantecam uses its report book for Prunus africana debarking. Raw material received at Plantecam is supplied only by the holders of a valid exploitation licence and the company will not accept material without this license.
Before any harvesting activity takes place the following procedures are undertaken:
· A preliminary inventory to determine the potential harvestable resource;
· Training (theoretical or practical) of collectors in sustainable practices of debarking or gathering.
In the case of the exploitation of Prunus africana for example, an operational team is composed of a team leader, prospectors, de-barkers and porters. This team is supervised by a camp leader who regularly provides a report of the quantities harvested, the number of de-barked trees, and the quality of de-barking according to the report book. The assessment of this exploitation activity to determine the sustainability of the harvesting is based on the following information:
· A regular estimate of field work following the norms of the report notes book; this allows an appreciation of the long-term health of trees, and the time necessary before re-exploitation can take place;
· A general forest inventory: for example there has been an intensive inventory of Prunus africana on Mount Cameroon. This inventory was undertaken in 1996-1997 by ONADEF (National Board for Forest Development) at the request of Plantecam and the Mount Cameroon Project. The results obtained have provided an overview of the density of Prunus africana and potential bark yield, thus permitting the potential for sustainable management of the remaining resource.
· A study of the natural stands of Prunus africana in certain key areas of Mount Cameroon with the aim of determining the rate of natural regeneration and hence future production.
Medicinal plant trade
Raw material (seeds, bark, etc.) often undergoes processing such as grinding (as in the case of Pausinystalia johimbe bark) or full extraction (e.g. Prunus africana) prior to trading. Processing in-country maximises revenues and attempts are made to add as much value to each product prior to export. Without exception, all material processed at the Plantecam factory is exported. Trade of the medicinal plant products is controlled by Plantecam's parent company in Paris, Groupe Fournier, and their commercial department deals with all contracts and negotiations regarding the sale of both raw and processed products.
To ensure the sustainable management of the medicinal plants exploited by the company, Plantecam has undertaken extensive cultivation trials with the objective of domesticating some key species as well as looking at the management of a number of these species in natural forest. This programme is comprised of a number of components:
(i) Inventory and sensitisation of the local populations (chiefs of villages, medicinal plants exploiters, common interest associations, non-governmental organisations, local communities) through workshops, training courses for demonstration (nursery, forest) in the wise management of natural forest and potential for domestication of some key species;
(ii) The integration of local communities in the protection and rational management of the forest through exploitation agreements such as the one signed with selected villages around Mount Cameroon. The immediate effects of this agreement are:
· The control of illegal over-exploitation;
· The improvement of farmers revenue and the development of social infrastructure in some villages (e.g. community hall in Mapanja);
· The provision of planting stock of Prunus africana and a guaranteed market for future bark harvests from cultivated sources;
· Controlled exploitation of wild trees under the supervision of Plantecam.
(iii) Production of planting stock of high-value species through bulk seed propagation;
(iv) Distribution of plants for plantations and agroforestry schemes with the ecological requirements of the species being taken into consideration prior to planting;
(v) Monitoring of planted material in both plantations and agroforestry systems;
(vi) Partnership with NGOs (Non Governmental Organisations), MINEF (Ministry of Environment and Forest) and research institutions such as the Limbe Botanic Garden to further the aims of forest conservation and sustainable exploitation;
(vii) The promotion of Prunus africana, Voacanga africana, Strophantus gratus and Physostigma venenosum cultivation through an active extension programme;
(viii) The creation of an arboretum in the factory location site, with the aim of acclimating medicinal plants. This arboretum has a wide collection of local and exotic plants species.
Figure 1. Plantecam nursery producing stock for replanting (Photo: Plantecam).
The sustainable development of medicinal plant exploitation depends on a combination of a number of factors:
· Research in agronomy, biochemistry, pharmacology;
· Appropriate legislation for the registration of traditional medicines ensuring the production of low cost medicine (herb tea, capsule, extract, syrup) for local people;
· A well-implemented forest policy ensuring that taxes due from exploitation are collected and equitably disbursed to the advantage of rural communities and those concerned with natural forest management;
· The provision of long concessions to medicinal plant exploiters thereby ensuring the interest of the company in the long-term health of the resource;
· The initiation of training programmes for trainers and extension workers for the popularisation of medicinal plant cultivation and appropriate associated agricultural practices (agroforestry; multi-strata culture);
· To make available information opportunities for medicinal plant development;
· The creation of a data bank for phytochemical, pharmaceutical, marketing and utilisation aspects of medicinal plant exploitation.
Figure 2. Confiscated bark of Prunus africana on Mount Cameroon (Photo: T. Sunderland).
