Ethnobotanical survey of medicinal fern species used by communities bordering Kalinzu Central Forest Reserve, Western Uganda

Abstract Introduction Across the globe, traditional medicine, particularly herbal remedies, is a cornerstone of healthcare. While the medicinal uses of ferns are widely recognized globally, their therapeutic potential in Uganda remains significantly underexplored compared to higher plants. This limited research creates a critical gap in our understanding of the medicinal capacities of ferns, leading to their neglect in drug development. The main aim of this study, therefore, was to document the medicinal fern species and their uses in communities bordering Kalinzu Central Forest Reserve (KCFR). Methods An ethnobotanical survey was conducted for 3 months (October, November, and December), 2024 in 20 villages bordering Kalinzu Central Forest Reserve (KCFR) in Kyamuhunga. The study utilized a semi-structured questionnaire and face-to-face interviews with 71 key informants to collect data on the use of ferns in herbal medicine. The questionnaire data was analyzed using various ethnobotanical indices, including Relative Frequency of Citation (RFC), Use Value (UV), Relative Importance (RI), Fidelity Level (FL), Informant Consensus Factor (ICF), and Combination Use Diversity Index (CUDI). Results Six fern species were documented for use in herbal medicine by communities around KCFR, and Pteridium capense was the most cited species. The use value (UV) index was highest for P. capense (0.72). The informant consensus factor (ICF) was highest for musculoskeletal illnesses (1.00), and the fidelity level (FL) was highest for Hypolepis sparsisora for treating burns (100%). Fronds were the most used part of the ferns in herbal medicine (76.06%), and dermal (smearing and rubbing) was the most common route of administration (57.75%). Conclusions Medicinal ferns are an important component of traditional herbal medicine in communities bordering KCFR. The study documented different medicinal fern species for treating various ailments in communities bordering KCFR. Pteridium capense was the most frequently cited species, used to treat various illnesses. These findings highlight the significant ethnobotanical knowledge of the local communities and suggest that further research into the pharmacological properties of these fern species, especially P. capense, is warranted. Further research should characterize and elucidate bioactive compounds responsible for such therapeutic values.