Weniwelgeta : Can we save this dwindling forest resource ?July 15, 2012, 7:49 pm
by Prof. Nimal Gunatilleke, University of Peradeniya
A newspaper report titled " Caught transporting weniwelgeta" appeared a few months ago in The Island newspaper and several related incidents that I came to know recently prompted me to spotlight on this disconcerting issue. Unsustainable harvesting or in general terms ‘plundering’ of dwindling natural resources for short-term commercial gain by a few, at the expense of a more eco-friendly and community oriented management regimen, is a serious impediment to conservation of biological diversity, indeed. The press report highlighted that the officers on duty at a police check point in Pothupitiya, a village situated in the valley between Sinharaja and Walankanda-Delgoda forest ranges, detected illegal transport of 750 kg of weniwelgeta stems packed in gunny bags for sale presumably harvested from the natural forests in the neighbourhood.
The second related incident was that a member of the "Sinharaja Sumithuro" from Wewagama area informed me that truck loads of weniwelgeta were harvested from the general area around Wewagama which includes a number of degraded forests adjoining Sinharaja-Morapitiya forests. He was given the impression by the harvesters that they are harvesting and collecting them legally having obtained permits from the local authorities.
The third related event was my own encounter near Kukule ganga hydropower project area on Kukule – Molkawa road where I recently came across a large scale harvesting operation of weniwelgeta stems in broad day light and drying them on the road while stacking them up on the road side for transport (see the pictures). The three persons who were engaged in the activity, informed me upon inquiry that they had obtained permits from the local Pradeshiya Saba authorities to harvest them having paid a fee.
Although these are three isolated incidents observed in recent times, over-exploitation of this important biological resource, may be rampant in other fragmented forests in the South- west of Sri Lanka. If this current level of extraction is permitted, Weniwelgeta will soon, if not already, be in the list of threatened plants of Sri Lanka. Hence this cautionary note and a suggestion for a way out.
Weniwelgeta botanically known as Coscinium fenestratum of the plant family Menispermaceae is a woody climber commonly found in lowland moist forests in Sri Lanka, South India and also extending into Kampuchea and West Malaysia. It is reputed to have antibacterial properties due primarily for the presence of the alkaloid ‘berberine’ and a family of its chemical variants. For this reason, it has been used in indigenous and Ayurvedic medicine as a much sought after remedy for a range of ailments from fever to tetanus. It is the traditional equivalent of paracetamol and marketed as one important constituent of the locally common ‘paspanguwa’ which is now coming to the market in various modern eye-catching packets. In addition, weniwelgeta is increasingly becoming popular in beauty therapy and as such, several herbal soap manufacturers are advertising them as ‘Weniwel soaps’. This pervasive usage of weniwel for a range of commercial products enjoying a resurgent demand may be one reason for this increased and unregulated levels of extraction of this plant from the wild.
While we can be happy on one hand that a traditional herbal product has found new and emerging markets both locally and overseas, our concern on the other hand is ‘can the current resource base cope up with the current and projected demand?’ This needs long-term research to come up with satisfactory answers. As researchers in biology of both timber and non-timber forest products with a view to their domestication, we realized this need several decades ago and have been studying the biology, ecology as well as its propagation and cultivation in a number of habitats with a view to reduce the extractive pressure on the wild populations.
Like nut meg, weniwel also has separate male and female plants and they grow better in partial light and therefore, more common like the rattans in degraded forests and forest edges. Also they seem to flower and fruit annually and the seed biology and germination requirements also have been worked out to some extent. We have grown weniwel seedlings in partially opened gaps created within Pinus plantations in one of our demonstration stands where we have successfully converted Pinus sp. to native species in the periphery of NW Sinharaja. We are pleased to inform that they have reached harvestable size in 15 years or more with no fertilizer added.
This demonstration site of Pinus conversion with local species in Sinharaja is being regularly used for teaching undergraduate and post-graduate students and also for workshops conducted for others at Sinharaja. Furthermore, this demonstration plot is available for any interested person to learn from it which is located on the alternate route to the forest entrance from Kudawa. It is our view that weniwel like rattans could be successfully cultivated in large scale under appropriate site conditions. At present, they show an abundance in degraded forests which had been rested after selective logging with the imposition of moratorium on logging. Since there appear to be a heavy pulse of extraction pressure on weniwel at present, it is likely that we may soon face a shortage of raw material for this emerging industry. In addition, their wild populations too would decline affecting their genetic diversity in the process.
At a time that industries based on non-timber forest resources such as weniwel, kithul, rattans, divul, kothala himbutu and a host of other health food, medicinal horticultural products are being promoted, and at least for those of whom the scientific information on their cultivation has already been worked out, well planned management plans need to be developed for ensuring a steady supply of the resource base required. For the other species, research should be conducted to bring them in to cultivation thus reducing the dependency on protected forest reserves which are playing an important role of conserving the genetic diversity of diverse assemblages of species for posterity.
In this connection, a suggestion made recently by the minister of economic development to establish at least ‘one forest for one village’ would be a way forward to incorporate these under-utilized non-timber forest resources through the active participation of local communities living around these forest patches most of which are degraded.
This concept of ‘one-forest for one village’ would be an excellent proposition in managing local ecosystem services ( provisioning, regulating, supporting and cultural services as detailed in the Millennium Ecosystem Assessment report) while providing benefits to local people. At the same time, it would also be worthwhile to consider how the existing Pinus plantations could be converted to native species stands enriched with both timber and non-timber species. This will help to enhance biological diversity and ensure environmental security on a local scale. On our part, we have shown that this could be done in the lowland wet zone areas using suites of such species of ecological and rural economic importance in Sinharaja and Hantana demonstration plots. More such studies are needed, if we are to conserve and utilize our rich biological heritage bringing in tangible benefits to the local communities.