Ethnobotanical study of medicinal plants and associated indigenous knowledge in the Agarfa and Lega-hida districts, Southeastern Ethiopia

Medicinal plants (MP) have long been used for magico-religious medicinal purposes in Ethiopia. However, much of the ethnobotanical knowledge remained underexplored and poorly documented. This study focused on documenting the ethnomedicinal knowledge of the local Oromo community in the Agarfa and Lega-hida districts, highlighting previously unreported medicinal uses and associated practices to support the validation of claims about medicinal plant healing potential. Eighty-one informants were purposefully selected and interviewed using a semi-structured questionnaire, focus group discussions, guided field observations, and specimen collection. Descriptive and inferential statistics were used to compute ethnomedicinal knowledge. The significance of documented MPs was further evaluated using quantitative indices along with Spearman’s correlation analysis. A total of 145 MPs were documented; of these, 69% were collected from the wild. Two recipe formulation methods were widely practiced: simple and polyherbal concoctions. This study documented 47 polyherbal formulations for the first time, comprising 2 to 11 MPs. Carissa spinarum L. Sida tenuicarpa Vollesen, and Kalanchoe laciniata (L.) DC. were frequently cited as simple remedies and/or as components of the polyherbal formulations. The recipes were mostly prepared as decoctions (27.6%) and were mainly administered orally (53.8%). The documented MPs were used to treat 16 disease categories across 108 human ailments, with the highest informant consensus factor (0.84) for skin diseases, followed by gastrointestinal diseases (0.82). C. spinarum L. had the highest use value (UV) (0.51) and relative frequency citation (RFC) (0.44), which could be a potential candidate for further ethnopharmacological investigation. The Spearman correlation coefficient between RFC and UV was 0.61, indicating a significant positive association. The present study documented 12 MPs with previously unreported medicinal uses. This highlighted the indigenous ethnomedicinal knowledge of local communities, underscoring the need for preservation, documentation, and scientific validation.