Characterization of density and selected anatomical features of stemwood and branchwood of E. cylindricum, E. angolense and K. ivorensis from natural forests in Ghana

Abstract

This study investigated density and some anatomical features, and also assessed the correlations among them in stem and branch woods of Entandrophragma cylindricum, Entandrophragma angolense and Khaya ivorensis. Branch and stem wood samples were sampled from two natural forest reserves. Wood density was determined in accordance with ISO 3131 whereas anatomical investigations followed IAWA committee’s recommendations-1989. Results indicated that at 5% level of significance, wood density was significantly higher in branchwood than stemwood for all three species. Generally for all the three species, significant differences were found in fibre length and vessel diameter between branchwood and stemwood of same species but no significant differences were found in both ray and axial parenchyma quantities. Stemwood density correlated significantly and positively with fibre (r = 0.408, p < 0.01) and ray parenchyma (r = 0.280, p < 0.05) proportions but negatively with fibre length (r = −0.528, p < 0.01), vessel lumen diameter (r = −0.304, p < 0.05) and axial parenchyma proportion (r = −0.679, p < 0.01). However, branchwood density correlated significantly and positively with fibre (r = 0.505; p < 0.01) and axial parenchyma (r = 0.385; p < 0.01) proportions but negatively with fibre length (r = −0.316, p < 0.05), vessel proportion (r = −0.486, p < 0.01) and ray parenchyma proportion (r = −0.357, p < 0.01). The study suggests that wood type (stem or branch) is an important factor to consider in terms of their effect on some properties of products produced from them, since differences in fibre length, vessel lumen diameter and vessel proportion could affect strength, porosity, leachability, natural durability and drying properties of wood.