TECHNICAL ROTATION AGE FOR NATURALLY-GROWN <em>BAMBUSA</em> <em>VULGARIS</em> FOR FIBRE, FUEL AND STRUCTURAL APPLICATION

Abstract

Basic properties of Bambusa vulgaris from different ages were examined to determine the optimum technical growth rotation for fuelwood, source of fibre and structural application. Bamboo culm samples aged 2, 3 and 4 years were taken from naturally growing bamboo stock in the Federal University of Technology, Akure, Nigeria. The density, porosity, shrinkage, swelling, fibre morphology and derived fibre values obtained from the geometry of the fibre, the fuel, chemical as well as the strength properties were determined. All the tests were conducted following the standards of Technical Association of Pulp and Paper Industry (TAPPI) and American Standard for Testing Materials (ASTM). The result showed that the maximum density (877.23 kg/m³) was attained at age 3 while the minimum culm density (755.22kg/m³) was attained at age 2. The minimum culm density is slightly above the minimum wood density requirement of pulp and paper industry. No significant variations existed in the extractive content, fuel properties, fibre dimensions and the derived values among ages. However, significant variation existed in porosity, density, holocellulose, α-cellulose, hemicelluloses and lignin content among ages. The silica content and all the mechanical properties varied significantly among ages except compression strength perpendicular to grain. Considering the basic characteristics of B. vulgaris at different ages, the recommended optimum technical rotation age for cellulosic fibre production is 2 years. For structural application, 3–4 years is considered the harvesting age, as density and strength start decreasing after age 3 except modulus of elasticity (MOE), while culms may be harvested for fuelwood at any age as it is not necessary to use matured culm.