RELATIONSHIP BETWEEN MECHANICAL PROPERTIES AND SELECTED ANATOMICAL FEATURES OF NTHOLO (PSEUDOLACHNOSTYLIS MAPROUNAEFOLIA)

Abstract

UETIMANE JR E & ALI AC. 2011. Relationship between mechanical properties and selected anatomical features of ntholo (Pseudolachnostylis maprounaefolia). The anatomical features of the sapwood and heartwood of ntholo (Pseudolachnostylis maprounaefolia) were studied and interrelated with physico–mechanical properties. The samples were randomly taken from five trees irrespective of their position within the tree. The objective was to determine the mechanical properties of ntholo, a lesser-used species from Mozambique, and compare this species with the most used species in order to assess its end-use as well as to study the anatomy–property relationship through correlation and regression. Anatomical features were used to predict density and mechanical properties whereas density, to predict mechanical properties. There were notable differences between density and mechanical performance of sapwood and heartwood. The higher density of heartwood (1023.7 kg m -3 ) compared with that of sapwood (758.9 kg m -3 ) contributed to these differences. In terms of anatomy–property relationship, fibre length was the only anatomical trait which correlated with all measured properties and so density correlated with mechanical properties. Apart from modulus of elasticity (MOE) in sapwood having high predictive power, no other significant regression equations were observed for both sapwood and heartwood properties. Regression analyses showed that density alone was a poor predictor. Sapwood properties were mainly influenced by tissue proportions, whereas heartwood properties, by fibre dimensions and vessel.