Health and Habitat
Across all cultures, for most of human history, doctors were effectively botanists, using medicinal plants as the primary source of medicines to treat disease. Medicinal plant use is still widespread in Africa, Asia and Latin America. In China and Vietnam, public health care programmes involving traditional medicines and traditional healers have been implemented very effectively. Sustainable use of medicinal plants remains a significant challenge, however.
Beginning in 1992, the People and Plants Initiative, the forerunner of People and Plants International (PPI), had a focal interest in the link between primary health care and medicinal plants conservation (see PPI Working Paper 1). PPI continues to build on the link between health care and biocultural diversity.
PPI works for effective primary health care through a better understanding of the links between people's health, plant conservation, and resource management at multiple scales from the habitat level to harvest of plants providing food, insect repellents or herbal medicines.
This PPI theme links directly to a key target (Target 13) of the Global Strategy for Plant Conservation (GSPC), a program of the United Nation's Convention on Biological Diversity. The GSPC seeks to slow the pace of plant extinction around the world by 2010.
GSPC Target 13 : The decline of plant resources, and associated indigenous and local knowledge innovations and practices, that support sustainable livelihoods, local food security and health care, halted.
Harvesting langsat, used for food and medicinal purposes. Photo: A.B. Cunningham Recognizing that plants are the basis of people’s livelihoods, including food security and health care, this GSPC target links to several widely agreed international development targets, including the Millennium Development Goals. At the UN Convention on Biological Diversity’s Conference of Parties meeting in 2002, PPI was identified as being one of three groups which could assist with steps to attain this goal, which relates not only to plants, but also the ethnobotanical knowledge associated with them. These links are dealt with in detail in the most recent book in the PPI series: Human Health and Forests: A Global Overview of Issues, Practice and Policy. C. Colfer (ed). London, England : Earthscan, 2008. Click here to read a chapter in the book: “Health, Habitats and Medicinal Plant Use.”
Since 2004, through support from IDRC, PPI has supported two training courses with the Keystone Foundation in 
Keystone-PPI field course, India, 2008. Photo: A.B. CunninghamIndia, the first near Pondicherry (2005) and the second in the Nigiri Hills, a region of global significance for plants conservation. Linked to these training courses have been research projects on the most extensively used medicinal bulb in southern Africa, blue squill (Merwillea plumbea), black dammar (Canarium strictum) and a rare cycad (Cycas circumnalis). PPI has also supported a PhD study by Heather McMillen on links between medicinal plant use, trade and health care in Tanzania. See below for further information on these projects.
Trade, Bulb Age and Impacts on Merwilla plumbea
After a successful international training course organized jointly by PPI and two Indian NGO’s, Keystone and ATREE (Ashoka Trust for Research in Ecology and the Environment) and supported by IDRC, researchers in India and southern Africa conducted three innovative studies in applied ethnobotany.
The southern African study, conducted by Viv Williams and Tilla Raimondo with support from PPI Steering 
Merwilla plumbea roots. Photo: A.B. Cunningham Committee member Tony Cunningham, showed for the first time that medicinal bulbs of Merwilla plumbea (formerly Scilla natalensis) can be aged accurately derived from counting persistent bulb scales.
This information is crucial for resource management linked to traditional health systems, showing that M. plumbea bulbs take at least 15 years to get to the preferred harvestable size.
Medicinal plant market, Durban, S. Africa. Photo: A.B. CunninghamIn 2006, it was estimated that 2.1 million wild harvested M. plumbea bulbs were sold in the Durban and Johannesburg medicinal plant markets.
New techniques like aging plants are essential to understand the complex interplay of harvest impacts, fire ecology and tenure need to be managed if viable wild populations are to be maintained in the long-term.
Download a summary of the study results, "Trade and harvesting impacts on Merwilla plumbea" PDF English.
Ethnomedicine in Tanzania
Heather McMillen’s dissertation research “Conserving the roots of trade: local ecological knowledge of ethnomedicines from Tanga, Tanzania markets” (2004-2006) documents links between forest resource use, ethnomedical practices and sustainable harvest needs. With support from PPI she conducted a local ecological knowledge survey on plant medicines, including those used to treat opportunistic infections of HIV/AIDS. She found
that knowledge of these medicinal plants is not primarily held
H. McMillen preparing specimen vouchers. Photo: H. McMillen by specialist healers or elderly, as was expected. It is distributed among stakeholders (vendors, healers, and harvesters) and a range of ages. She also found that most of the salient market plants are widely distributed in terms of geography and habitat type, but there are at least two, Ocotea usambarensis and Warburgia stuhlmannii, that are more unique and are from biodiversity hotspots.
While medicinal plant harvest does not appear to pose a serious threat to medicinal plants at present, these plants are also subjected to intensive harvesting for competing uses (timber, charcoal), a pressure which is compounded by shrinking habitats. The findings demonstrate that plant medicines are important resources to health, culture, and livelihoods and therefore have potential to help promote the conservation of threatened habitats and species.