EFFECT OF NATURAL WEATHERING ON THE PHYSICAL PROPERTIES OF Nauclea diderrichii WOOD
I. M. ADENIYI *
Department of Forest Products Development and Utilization, Forestry Research Institute of Nigeria, P.M.B 5054, Forest Hill, Jericho Estate, Ibadan, Oyo-State of Nigeria, Ibadan, Nigeria
J. A. FUWAPE
Forestry and Wood Technology Department, Federal University of Technology Akure, P.M.B 704, Akure, Ondo State, Nigeria
A. O. OLUYEGE
Forestry and Wood Technology Department, Federal University of Technology Akure, P.M.B 704, Akure, Ondo State, Nigeria
G. T. SALAUDEEN
Department of Forest Products Development and Utilization, Forestry Research Institute of Nigeria, P.M.B 5054, Forest Hill, Jericho Estate, Ibadan, Oyo-State of Nigeria, Ibadan, Nigeria
*Author to whom correspondence should be addressed.
Abstract
Effect of natural weathering on the physical properties of Nauclea diderrichii wood was investigated in this study. Twenty four wood samples were obtained from four mature trees of Nauclea diderrichii. Physical properties investigated include specific density, texture and weight. Main changes in wood samples of N. diderrichii after six months of exposure to weathering factors include discoloration, surface checking, raised grain and the eventual loss of fibres. 4.89% and 3.86% of wood materials from sapwood and heartwood respectively were lost after exposure as some wood materials were eroded away during exposure. The study also showed that average values of moisture content were reduced from the initial value of 16.81% before exposure to 12.40% after six month of exposure. Wood degradation and loss of aesthetic value resulting from discoloration and loss of fibres from wood samples were attributed to prolonged exposure to weathering factors such as rainfall, humidity, temperature wind and sunlight. The adverse effects of weathering on the wood therefore indicated that wood materials should not be left for too long in the open before use, and that wood exposed to rainfall, humidity, et.c before application of preservatives or coatings stand the risk of degradation before protection. The study therefore recommended that wood protection against natural weathering be commenced immediately after the lumber is brought to the log yard as this step might reduce waste in the regions of wood degraded.
Keywords: Weathering, fibres, discoloration, degradation and exposure