The commercial harvest of devil's claw (Harpagophytum spp.) in southern Africa: The devil's in the details

Devil's claw is the common name for two species in the genus Harpagophytum. Their root extracts contain the iridoid glycoside, harpagoside, which has been found to be effective in the treatment of degenerative rheumatoid arthritis, osteoarthritis, tendonitis, kidney inflammation, and heart disease. Most of the world's supply comes from Namibia, with lesser amounts from South Africa and Botswana. In 2002, the peak year of export, 1018 tonnes of dried tubers were exported from southern Africa, representing the harvest of millions of plants. In 2001, sales in Germany were estimated at 30 M euros, accounting for 74% of the prescriptions for rheumatism. Harvest has improved income levels in marginalized communities but it has also raised questions of sustainability. In 2000, recommendations were made to the Convention on the International Trade in Endangered Species (CITES) to add devil's claw to Appendix II. In 2004, the proposal was formally withdrawn due to the efforts of the range states to address sustainability issues. Replacing wild collection with cultivation has generated a debate on the positive and negative effects on harvester income and rural farmers. Successful cultivation efforts have involved micropropagation techniques and growing the plant without water or fertilizers. The governments of the main range states are working with local communities to develop policies and regulations to protect the species and to determine a sustainable harvest.