The effect of teratosphaeria stem canker on the anatomical structural and physical properties of Eucalyptus grandis

Abstract

The increasing demand for timber and other wood products accompanied by a tremendous decline in the natural forest cover has necessitated the establishment of Eucalyptus plantations throughout the country. However, these plantations are experiencing a major problem of canker diseases such as Teratosphaeria cankers. In this study, the effects of Teratosphaeria cankers on the wood structure and physical properties were examined. Test specimens from both the normal and diseased wood were collected and prepared for the tests. The physical properties tests were performed in accordance to the British Standards (1957) while wood structure of normal and diseased wood was compared macroscopically and microscopically in the laboratory. Comparison tests showed that there was a significant difference in the basic density and volumetric shrinkage of normal and diseased wood (P=0.000), due to increased number of thick celled fibres in the diseased wood. In addition, macroscopically and microscopically, there were differences in the wood structure between normal and diseased wood. It is therefore recommended that the sector needs to set out standards to regulate the sale and use of timber especially from diseased trees.