keywords: Slenderness coefficient; stability index; stratified random sampling; taxonomic families; wind-induced damage.
The contribution of trees to environmental, social, and economic wellbeing cannot be overestimated. Trees contribute significantly to human health, environmental quality, aesthetic quality, and the financial security of humankind. This study assessed the stability of tree species in the University of Ilorin permanent site, Nigeria, using slenderness coefficient as the stability index. A stratified random sampling technique was used by dividing the study areas into five different strata (academic area, administrative area, business area, student hall, and religious area). Diameter at breast height (Dbh) and the total height of living trees with Dbh ≥ 10cm were measured while basal area, slenderness coefficient, and relative density for trees in the study area were computed using relevant mathematical equations. The study observed one thousand four hundred and ninety (1490) tree species distributed across 18 taxonomic families in the study area. Daniella oliveri was the most abundant species with a relative density of 20.27%, while Cumbretum erythrophyllum was the least occurring species (0.07% relative density). The mean Dbh, height, and basal area for trees were 79.42±13.564 cm, 18.66±3.456 m, and 0.47±0.165 m 2 , respectively. About 77.85% of the trees were of low slenderness coefficient, 14.97% were of moderate slenderness coefficient, and 7.18% were of high slenderness coefficient. It implies that most of the trees were not susceptible to wind-induced damage. The study, therefore, recommends that tree species with high slenderness coefficient be removed and replaced with young trees at a ratio of 3:1.