The Effect of Finishing Material on Some Selected Physical Properties of C. lusitanica Grown at Arsi Forest Enterprise, Munesa District - Oromia – Ethiopia

Abstract

Basic wood density (D) and initial moisture content (MC) are the two important wood properties for solid timber applications; especially structural timber application is strongly related to wood density. Other physical properties which are highly affect the basic density such as; dimensional stability, water absorption ability (WAA), and anti-swelling efficiency (ASE) are the dominant wood properties for the utilization of wood in different way. There are many technological factors that determine the quality and aesthetic values of the finished woodworking products. Finishing technology is among the factors that play a great role in determining the durability and visual value of the end product. In this study the effect of wood finishing materials were studied on the above listed physical properties of C. lusitanica species grown at Arsi Forest Enterprise- Munesa District – Ethiopia. A total of 10 trees from C. lusitanica stand were felled and a replicates of green sample discs having a dimension of about 3cm thick were taken from the butt, middle and top portion of the tree, to investigate moisture and density variation along the tree height. In addition to these discs, a total of 90 specimens from 10 trees (i.e. 3 specimens from each tree, 1 specimens from one portion of the tree) having a dimension of about [2 x 2 cm (cross section) and 3 cm long] were prepared from three trees were prepared for shrinkage, WAA and ASE analysis. The Statistical Analysis Software (SAS) were used to analyze the data using analysis of variance (ANOVA) procedure and a least significant difference (LSD) method were used for mean comparison at P ≤ 0.05. All variables were evaluated along the tree height and among two different finishing treatments. Among all studied properties a significance difference exists in basic wood density wood shrinkage and water absorption ability among the three different tree portions and among the treatments. Basic wood density showed an increasing trend as the tree height increases, unlikely both tangential and radial shrinkage decreases as the tree height increases. Water absorption ability showed a less value in varnish treatments. In the other way, the initial moisture content and the anti-swelling efficiency of the species were revealed a significant difference along the tree height and different finishing materials.

Keywords: Finishing material, tree position, wood physical properties, Cupressus lusitanica, Ethiopia.