Highly localised traditional knowledge of Mien medicinal plants in Chiang Rai, Thailand

Abstract

The Mien ethnic people have migrated from China to Thailand over centuries and traditionally settled in remote areas of northern Thailand. They relied extensively on the local ecosystem for construction, food, fodder, and medicine. There are only a few studies of Mien traditional knowledge in China and Nan, Thailand. This study examines the knowledge of medicinal plants used by Mien in Chiang Rai, Thailand. We investigated traditional knowledge of medicinal plants in three Mien villages in Thailand, highlighting a crucial yet vulnerable cultural heritage. For this study, we interviewed five traditional healers to gather data about their specialist medicinal uses of plants and an additional 90 villagers, who did not have this specialist knowledge, about their ethnobotanical understanding. Each use report was categorised using the International Classification of Primary Health Care. The usefulness of the plant taxa was assessed with the use value index. Our interviews revealed 352 use reports based on 77 plant species in 46 families, predominantly addressing women's health and digestive conditions. The most used plant families were Asteraceae, Rubiaceae, Fabaceae, Euphorbiaceae, Zingiberaceae, Plantaginaceae, Acanthaceae, Rhamnaceae, Amaranthaceae, Lamiaceae, and Vitaceae. The most frequently used species were Clausena excavata, Ricinus communis, Blumea balsamifera, Chloranthus elatior, Monosis volkameriifolia, Plantago major, Plumbago zeylanica, and Zingiber montanum, highlighting their critical roles in traditional medicinal practices. The Mien people in Chiang Rai, Thailand, possess substantial traditional knowledge regarding medicinal plants, especially for women's healthcare. The identification of numerous species in this study based on traditional usage raises concerns about the effect of ongoing acculturation of ethnic minorities in the region and the potential erosion of traditional knowledge. Some of the identified knowledge is highly localised in the three villages, making the conservation of that knowledge particularly important. We strongly advocate further initiatives aimed at conserving traditional Mien knowledge, as well as more studies in Laos PDR and Vietnam to cover the Mien's migration line. Read the free Plain Language Summary for this article on the Journal blog.