The Association Between Cellulose Crystallite Width and Tension Wood Occurrence in Eucalyptus Globulus

The association between cellulose crystallite width and the occurrence of tension wood was assessed for Eucalyptus globulus Labill., a commercially important plantation hardwood species. Crystallite width (uncorrected for instrumental broadening) was determined from X-ray diffraction patterns collected on SilviScan-2, an instrument developed for the rapid assessment of wood microstructure. Comparisons of crystallite widths were made using 66 samples of tension wood and normal wood selected randomly from one tree known to have abundant tension wood. Tension wood was found to have significantly wider crystallites than normal wood. The mean crystallite widths were 3.6 nm for tension wood and 3.2 nm for normal wood. The normal wood crystallite widths were consistent with those reported in previous studies, allowing for an experimental broadening equivalent to about 0.5 nm in this work. This study demonstrates that SilviScan-2 is useful for the detection of tension wood in solid wood samples such as increment cores.