Morphological characteristics and chemical components of Ulmus glabra, Ulmus compestris, Zelkova carpinifolia, Celtis australis woods

The suitability of wood and non-wood species for use in pulp and paper industry can be predicted by their morphological and chemical characteristics. In this research, morphological and chemical properties of four species of Ulmacea family, Ulmus glabra, Ulmus compestris, Zelkova carpinifolia and Celtis australis have been compared. Of each species, three cross section discs of 5 cm thickness were selected. Wood slivers of three zones: near to pith, middle part and near to bark wood were macerated in a mixture of acetic acid and hydrogen peroxide at 60°C for 48 hours. Biometric coefficients of fibers in three zones and four species have been measured and analyzed by a factorial, complete randomized block design. Results showed that, Zelkova carpinifolia wood has the least lignin, ash and extractives as well as the highest cellulose. The fibers of, Zelkova carpinifoliahas has the highest slenderness ratio, Runkel ratio and hence is most suitable species in Ulmacea family for paper industry. Fiber length and wall thickness near to bark zone was significantly higer compared to the pit zone. Therefore it is suggested that the mechanical properties of pulp of this three zones are different.