Key medicinal plants used for cancer, malaria and other remedies are being over-exploited potentially putting the health of millions at risk.
The warning comes from international conservation group Plantlife this week. According to their report, almost one third of medicinal species could become extinct, with losses reported in China, India, Kenya, Nepal, Tanzania and Uganda.
Factors in this loss include commercial over-harvesting, pollution, competition from invasive species and habitat destruction.
The solution, says the report's author, Alan Hamilton, is to provide local communities with incentives to protect these plants.
This approach has already proved successful in Uganda, where a sustainable supply of low-cost malaria treatments has been established, and China, which has created a community-run medicinal plant reserve. Ten such grass-roots projects are highlighted in the report.
Improving health, earning an income and maintaining cultural traditions are important in motivating people to conserve medicinal plants and thus the habitats, Hamilton says.