Abstract:
Medicinal plants are essential part of the variety of cultures among ethnic groups in Ethiopia and have been used in several parts of the world. The purpose of the study was to document traditional medicinal plants species and indigenous knowledge of the inhabitant people used to treat both human and livestock ailments in and around Chato Forest, Horo District, Western Oromia, Ethiopia. The study involved traditional healers, knowledgeable elders and local people. Various ethnobotanical techniques were used to collect and analyze the data including: semi- structured interview, guided field walk and observation, group discussion, preference raking and paired comparison, direct matrix ranking and fidelity level index, combined with descriptive statistical analysis. Sixty five informants from four kebeles and 16 local study areas were included in the study. A total of 97medicinal plant species 65(67.01%) wild, 11(11.34 %) cultivated and 21(21.64 %) both wild and cultivated were categorized into 92 genera and 53 families. Of these 76 (78.35 %) treat 48 human ailments, 40 (43.47 %) 16 livestock ailment and 34 (35.05 %) treat both human and livestock ailments. Of these herbs 41 (40.19 %), shrubs 32 (31.37 %) and liana 22 (14.7 %) were mainly used growth forms. Leaves 40 (41.23%), root 27 (27.83 %) and seed 14 (14.43 %) were primarily used parts. Where as pounding 32 (32.98 %), powdering 23 (23.71 %) and concoction 5(5.15 %) were predominantly used modes of preparation. Oral 42 (43.29 %), dermal 32 (32.98 %) and nasal 13 (13.98 %) were major routes of administration. About 65 (67 %) the medicine were prepared and used fresh, 22 (23 %) dried and 10 (10 %) both fresh and dry. Medicinal plants were utilized for forage, fencing, fire wood, construction, charcoal and furniture needs. The highest informant consensus was documented for Thalictrum rhynchocarpum (0.98), Acmella caulirhiza (0.97), Allium sativum (0.96) and Ocimum urticifolium (0.96) informants ranking them 1st, 2nd and 3rd respectively for their medicinal value. Preference ranking, paired comparison and fidelity level index showed the efficacy, popularity and preference people have for some species over the other for different uses and in treating ailments. Awareness education and announcement from health professional have contributed in making the younger generation indisposed to practice and retain the knowledge. Encroachment (40 %), new settlement (23.07 %) and fire wood (20 %) were major threat factors to medicinal plants. All inclusive conservation action should be taken to preserve both medicinal plants and the indigenous knowledge.