Tree slenderness coefficients of selected tree species in Oluwa Forest Reserve, Ondo State, Nigeria

Abstract

Tree Slenderness Coefficient (TSC) is useful in determining tree stability to wind throw. This study assessed the TSC and  its relationship to Diameter at Breast Height (DBH) of trees in Oluwa forest reserve, Nigeria. A total of 104 trees were  measured, belonging to 30 species and 18 families. Three species (Celtis zenkeri, Ricinodendron heudolotti and Picralima  nitida) were purposively selected for this study based on abundance. The DBH and height of all trees with  DBH ≥ 10cm were measured. Tree volume and TSC were calculated, tree growth characteristics summarized, and results  presented using tables and charts. Picralima nitida and Ricinodendron heudolotti recorded no trees in the high  slenderness categories (>99) while Celtis zenkeri had 31.25% of its population in the high slenderness coefficient  category. Trees with TSC (<70) indicates high resistance to wind damage, while trees with TSC (>99) will implied low  resistance to wind throw. Based on the findings from this study, it can be observed that most of the trees in Oluwa  forest have the ability to withstand windthrow