Tree Species Diversity in Urban Areas of Ijesa Region of Osun State, Nigeria

Abstract

Tree species diversity in the urban areas of Ijesa region of Osun State, Nigeria, wasdetermined through the use of field visits and semi-structured interviews ofresidents in six urban communities that were selected from six Ijesa LocalGovernment Areas of the state. In each community, three routes were selected fromthe centre of the community and used for the study. In each route, a 500m distancewas measured out and at every 50m distance; an inventory of trees and housessituated within 10m radius of the centre of the road was carried out. Also in eachroute, 10 residents along the route were interviewed. Similarities in the occurrenceof tree species were determined among the selected communities. Also, the indices ofdiversity were calculated on the identified tree species in each community. Resultsobtained revealed a density of 2,156 tree species, belonging to 34 species and 23families. 64 % of the trees were preserved from wildlings. The trees were valued forthe fresh air and shade they provided and their ethnomedicine importance. Over-exploitation, browsing by animals, insects infestation, harbouring of reptiles andbirds and unplanned land use were identified as disincentives to planting trees inurban areas of the region. High similarity but low diversity values were obtained onthe occurrence and diversity of the identified trees in most of the communities usedin this study. Strategies that would improve urban forestry in the region wereprescribed