Determination of basic density and strength properties of Cordia Africana lam. Grown in agroforestry system in Lushoto, Tanga

Abstract

Basic density and strength properties of Cordia africana Lam. grown in agroforestry systems in Lushoto, Tanga were determined. Six sample trees were randomly selected in the same farm at Shashui village near Soni. After measuring dbh the trees were felled and total tree height recorded. Four discs were cut at breast height, 30%, 60% and 90% of the total tree height for basic density determination. A one metre long log was cut above 1.3m for strength properties determination. A central plank measuring 6cm including pith was sawn in east-west direction from each log. Standard methods were used in determination of basic density and strength properties. The main findings of this study were as follows: Basic density was 0.40g/cm3; Basic density increased moderately from the pith to a certain point after which it remained more or less constant; Basic density decreased from the butt to the top of the tree. Mean values for modulus of rupture, modulus of elasticity, maximum crushing stress and shear parallel to grain, compression stress and cleavage perpendicular to grain were lower than those for common hardwoods such as Ocotea usambarensis and Albizia spp. found in Lushoto. There was positive correlation between basic density and strength properties. It was recommended that, wood from C. africana grown in Lushoto and other areas with similar soil and climatic conditions could be used for light construction work and furniture making. It was further recommended that, more studies should be done in other geographical conditions where the species is grown so as to make concrete conclusions on efficient utilization of the species.