**2. General data on medicinal species**

In this study, all investigated species were as the scientific names, Vietnamese name, name of Tay ethnic group, parts used, tree-forms, and disease treated (List of medicinal plants of Tay ethnic group in Thai Nguyen province do not show).

During (2018–2021), the result of research on medicinal plants of the Tay ethnic group in Thai Nguyen province obtained 321 species of medicinal plants belonging to 253 genera and 103 families of 3 divisions of vascular plants in Vietnam (**Table 1**, [6]).

Among these, the most diverse families (over 10 species) that the Tay people in Thai Nguyen province use as medicine are the as below: 20 species belonging to Euphorbiaceae, 19 species to Asteraceae, 13 species to Acanthaceae and Rutaceae respectively, 12 species to Fabaceae and 11 species to Poaceae (**Figure 2**). These families have been widely used in the Indo-Burma region for their medicinal properties [7–13].
