Health, habitats and medicinal plant use

Medicinal plants are the roots of medical practice. Of the 12,807 species used in traditional Chinese medicine, for example, 11,146 are plant species (Zhao, 2004). Medicinal plant uses range from anti-microbial ‘chewing sticks ’ for dental care and the treatment of internal parasites to symbolic uses. In fact, of the global total of 422,000 flowering plant species, more than 50,000 are used for medicinal purposes, with an estimated 2500 species of medicinal and aromatic plants traded worldwide, most still collected from wild sources (Schippmann et al, 2003). Across all cultures, for most of human history, all doctors effectively were botanists, using medicinal plants as the primary source of medicines to treat disease. In Europe and North America, however, commercial pharmaceutical production since the 1950s, a medical ‘effectiveness revolution ’ (Stevens and Milne, 1997) and randomized clinical trials have altered attitudes towards the botanical roots of medicine. Nevertheless, public health-care programmes involving traditional medicines and traditional healers have been implemented in many parts of the world (see Chapter 14, this volume). In China and Vietnam, for example, a long, well-documented history of medicine linked with significant