Floristic composition and community types of Gedo Dry Evergreen Montane Forest, West Shewa, Ethiopia

This study was conducted on Gedo Dry Evergreen Montane Forest in West Shewa Zone of Oromia National Regional State, 182–196 km west of Finfinne (Addis Ababa). The objective of the study was to determine floristic composition and community types of Gedo Forest. Systematic sampling method was used to collect vegetation data from 72 (20 m × 20 m) and subplots of 1 m × 1 m at the four corners and the center of the large quadrat for herbaceous plants. Vegetation classification was performed using PC-ORD software package. Hence four plant community types (clusters) were identified from the hierarchal cluster analysis using PC-ORD version 5 computer programme namely Chionanthus mildbraedii-Olea capensis subsp. Macrocarpa, Brucea antidysenterica-Allophylus abyssinicus, Maesa lanceolata-Vernonia auriculifera-Olea europaea subsp. cuspidata, Gnidia glauca-Echinops macrochaetus-Olinia rochetiana community types. Sorensen's similarity coefficient was used to detect similarities and dissimilarities among communities. Shannon-Wiener diversity index was applied to quantify species diversity and richness. A total of two hundred thirty five species of plants (herbs, shrubs, lianas and trees) were recorded. One hundred and forty of the species collected from sample plots were used for floristic analysis. The rest, 95, were collected out of sample plots but from the forest and used to describe the complete floristic list. Asteraceae is the most dominant family with 36 species in 24 genera followed by Fabaceae with 16 species in 14 genera and Lamiaceae with 16 species and 13 genera. Out of the plants identified in this study, 25 were endemic species which have been included in the preliminary list assessed for IUCN Red Data List. The forest was compared with five dry evergreen forests of Ethiopia which is vital for general conservation and management of the forests and particular to endemic species for the country's priority sites.