Variations in Physico-Mechanical Properties of Lonchocarpus sericeus (Poir), a Lesser-Used Species in West Africa

Abstract

Abstract This study investigates the properties of Lonchocarpus sericeus to determine its potential use for timber. Three matured trees of L. sericeus were selected from a forest located in Longe Village, Oluyole Local Government Area in Oyo State, Nigeria. Discs from the harvested trees were collected at the base (10%), middle (50%), and top (90%) and further partitioned into inner wood, center wood, and outer wood. An investigation was carried out to characterize the wood age, density, shrinkage, impact strength, modulus of elasticity, modulus of rupture, compressive, and shear strength. The ages were 28, 29 and 32 years. The mean wood density at 12 percent moisture content was 836.63 kg/m3, which shows that it belongs to the high-density wood category. The mean shrinkage values in the radial, tangential, and longitudinal directions were 2.50, 3.99, and 0.78 percent respectively; the volumetric shrinkage was 6.36 percent. These shrinkage values were indicative of good dimensional stability. The mean impact bending strength, modulus of rupture, modulus of elasticity, maximum shear strength parallel to grain, and maximum compression strength parallel to the grain were 24.14, 114.18, 11,276, 12.76, and 47.16 N/mm2, respectively. End-use assessments suggest that the wood species can be used in similar applications as well-known timbers. The study found L. sericeus to be very dense with high strength in comparison to well-known timbers. It was observed that the mechanical properties of the species decrease from the base to the top and also increase from the outer wood to the core wood.