The strength properties of the sapwood and heartwood of two lesser timber species used for furniture and construction

Abstract

<title>Abstract</title> In Ghana, there are several underused timber species that could substitute for the inadequate conventional species used in the furniture and construction industries. However, these industries continuously face persistent timber shortages. Additionally, due to the differences in strength between sapwood and heartwood, differences in the strength properties of <italic>Senna siamea</italic> (Cassia) and <italic>Azadirachta indica A. Juss</italic> (Neem) sapwood and heartwood should be determined. The aim of the study was to determine the modulus of elasticity (MOE), modulus of rupture (MOR), compression strength parallel to grain, and shear strength parallel to grain of sapwood and heartwood from Neem and Cassia trees for furniture and construction. The mixed analysis of variance (mixed ANOVA) test showed that all the stated properties of heartwood and sapwood from the two species were significantly different, with heartwood consistently demonstrating higher values than sapwood for both species. The findings indicated that the strength of the sapwood and heartwood of both species are comparable to those of key timber species such as <italic>Aningeria altissima</italic> (Asanfena), <italic>Milicia excelsa</italic> (Odum), and <italic>Piptadeniastrum africanum</italic> (Dahoma). It is important to consider the differences in strength between sapwood and heartwood from Neem and Cassia when selecting the species for furniture and construction work, particularly in applications that demand specific attention.