Within-Tree and Tree-Age Variation of Selected Anatomical Properties of the Wood of Ugandan-Grown Eucalyptus grandis

Abstract

The challenges of utilizing Eucalyptus grandis thinnings prompted a study into its anatomical properties with the aim of identifying its potential based on the within-tree axial and tree-age variation. Fiber length, fiber diameter, vessel length, vessel diameter, vessel average, ray height, and ray frequency at 3, 6, 9, and 12 years were studied. Axial sample portions at 25, 50, and 75 percent of tree height were collected from western Uganda and prepared for maceration, microtomy, and microscopy. Analysis of variance and Tukey's test were used to obtain axial and tree-age variation. Fiber length (819 to 1,077 μm) decreased axially in higher tree ages of 6, 9, and 12 years and increased with tree age. Fiber diameter (10 to 13.4 μm) varied inconsistently axially and decreased with tree age. Vessel length had no consistent axial pattern but decreased with tree age (338 to 548 μm). Vessel diameter showed higher values at 75 percent and increased with tree age (93 to 138 μm). Vessel average did not vary axially but decreased with tree age (8 to 11 vessels per mm2). Ray height did not vary axially but increased with tree age (107 to 278 μm). Ray frequency decreased with tree age (8 to 10 rays per mm2). E. grandis trees at the ages of 3, 6, 9, and 12 years have anatomical properties suitable for production of strong pulps although with a modest proportion of fines. Comparative research on cloned E. grandis varieties and their implied industrial potential would be appropriate to improve utilization of this fast-growing tree species.

Influence of Cambial Age and Axial Height on the Spatial Patterns of Xylem Traits in Catalpa bungei, a Ring-Porous Tree Species Native to China

“…Relatively stable fibre lumen diameter values with cambial age and axial height suggested this mechanical trait was not affected by these two factors, in comparison with vessel-related and thus hydraulic traits. However, decreased fibre length and latewood fibre wall thickness to diameter ratio with axial height agrees with a former study [67], and might be associated with declined xylem water potential to the crown and thus the vertical drop in cell turgor pressure. This demonstrates that the cell turgor gradient affects cell elongations during cell differentiation, although the gradient might be rather small [68][69][70][71].…”

Determination of the Boundary between Juvenile–Mature Wood of Diospyros kaki and Their Wood Anatomical Variations

“…The same result was reported by Tavares et al (2011), Taylor (1973), and Zobel and Buijtenen (1989), where the fiber length was essentially the same at all heights and was not influenced by height. Sseremba et al (2016) reported that fiber length decreased from the base to the top of the tree.…”

Effect of Chromated Copper Arsenate impregnation treatment on flexural and shear properties of Glue Laminated Eucalyptus grandis

“…In fact, plantation grown Eucalyptus is currently the top of the previously lesser utilised species preferred for manufacturing a variety of products such as furniture, wood cabinets and house roofing. It has a high biomass accumulation rate resulting into a maturity span between 6-12 years depending on the end-use however, the average harvesting time for most construction works is 10 years (Sseremba et al, 2016).…”