Selected Physical Properties and Microscopic Description of Ziziphus mauritiana Lam. Wood in Sudano-Sahelian Region of Nigeria

Abstract

Background and Objective: Wood is a hard, fibrous tissue found in many trees. It has been used for hundreds of thousands of years for fuel, construction and industrial raw materials.  Ziziphus mauritiana is a tropical fruit tree species, belonging to the family Rhamnaceae, the specie is abundant in Sudano-sahelion region of Nigeria and it has been reported to have several medicinal uses from the leaves, stem and roots, but technical information on the use of the wood for construction purposes is limited. Therefore, determinations of selected physical and microscopic description of the wood of Z. mauritiana as a potential wood material for timber were investigated. Materials and Methods: Three matured trees of Z. mauritiana were felled from a research plantation of the Department of Forestry and Wildlife within the University of Maiduguri, in the North-eastern part of Nigeria and cross-cut into billets at the base, middle and top of the stems with estimated age of 7, 6 and 6 years old accordingly from the three sampled trees. Discs were obtained from each billet for determination of Physical properties (Bark, Bast, Sapwood, heartwood and pith proportion, Moisture content (MC), Density and some microscopic description (fibre and parenchyma cells) were all determined. Results: The average wood density of the sampled trees stood at 0.55±0.01g/cm3 and decreased from base to top. Similarly, moisture content decreased from 75.66±3.83% at the base to 54.08±1.19% at the top of the sampling height. The volumetric shrinkage is the total shrinkage in wood volume and it amounted to 10.11±3.17%. Averagely, bast accounted for 3.56±0.70%, 6.50±0.89%, 69.38±0.50 %, 16.00±3.23% and 10.38±1.96 % for bark, sapwood, heartwood and pith proportions respectively across the stem.  Conclusion: The wood of Z. mauritiana is heavy. Within tree, wood density decreased from the base to the top. The range of values obtained in this study fall within the range of 450-750 kg/m-3 for species suitable for furniture, sheeting and lining, parquet, veneer wood for peeling and slicing with large vessel size and parenchyma cells. The range of values of volumetric shrinkage along the height and radial position shows that the wood is dimensionally stable. This was evident in the low tangential–radial shrinkage ratios recorded. Thus, indicating a low risk of deformation in wood during seasoning.Â