ABSTRACT

The study assessed the effect of plantation sites on some wood and paper properties of Pinus caribeae (Morelet) grown in Abia State, South East. Wood samples were collected from the sample plots located in Okwute plantations in Umuahia North and Ukpom in Bende LGAs established in 1983. Ten well formed-trees were felled from each plantation site. Diameter at breast height (DBH) and the four cardinal points were marked before the trees were felled. A total of 120 discs of 50 millimeters (mm) in thickness were obtained at 6 tree height levels of DBH, 10%, 30%, 50%, 70% and 90% of the trees felled. Each disc was sawn radially from the bark to the pith and partitioned into inner wood (A), middle wood (B) and outer wood (C) based on the number of annual rings counted from the pith to the bark. The experimental layout was a 3 factorial experiment in a completely randomized design (CRD) with 10 replicates. Data obtained were analyzed using Descriptive statistics, analyses of variance, correlation and regression. The Least Significant Difference (LSD) test was used to separate means that tested statistically significant. Relationship between wood density and other properties of the species tested showed that, Moisture content, Lignin content, solubility in 1% NaOH, Cell wall thickness, Tracheid length, Tracheid diameter, lumen width and Coefficient of slenderness were statistically significant (p < 0.05). Interactions between location, height levels of tree and wood types among the wood properties assessed were not significant (p < 0.05). Mean values for density were 593.5kg/m3 in Umuahia and 648.5kg/m3 in Bende plantations. Variations in wood density due to levels oftree height was statistically significant (p < 0.05) especially at 10% (618.09) and 50% (676.20). Moisture content variationss in the two plantations were significantly different (p <0.05). solubility in 1% NaOH was significant between location and wood types (p <0.05). Also, cell wall thickness had a mean of 1.25pm and 1.3pm in Umuahia and Bende plantations respectively with no significance (p < 0.05) in all other sources of variations. Tracheid length had a mean of 153gm in Umuahia and 199pm in Bende . Tree height levels, wood types and location did not show any significant effect on trachied length variations (p < 0.05). The various interactions of the main factors in Tracheid diameter were not also significant (p < 0.05). Umuahia and Bende plantations had a mean lumen width of 2.35pm and 2.2pm respectively which was not significant (p < 0.05) also among wood types, level and locations. The mean lignin content in Umuahia and Bende were 24.9% and 27.7% respectively although effect of location was not significantly different (p < 0.05). Moreover, the means of runkel ratio (0.52 in Umuahia and 0.53 in Bende), slenderness index (33.28% in Umuahia and 33.69% in Bende) and coefficient of slenderness (48.17% in Umuahia and 47.69% in Bende) were also not significantly different (p <0.05). Interactions of the factors were not statistically significant to cause variations in the chemical and physical properties ofthe species tested. It is recommended that the plantations be harvested without delay since pulp yield is associated with wood density. It has been established from this study and from other researchers that wood density decreased with increasing age, otherwise it would find alternative use in wood based panel industries notwithstanding excellent values oftracheid derivatives obtained from this study.