Influence of espacement on branch characteristics and occlusion in Eucalyptus delegatensis.  W. D. Incoll and R. J. McKimm.  November 1985.  10 pp. (unpubl.)

SUMMARY

Variation in both external and occluded branching and internal defects following occlusion, attributable to variation in tree spacing, were examined in a spacing trial of 20-year-old Eucalyptus delegatensis R. T. Baker (alpine ash) at Mount Macedon.

Significant differences were found between the frequency of branching at the various spacings, which ranged from 1.7 m to 6.9 m. Total cross-sectional area of branches also varied similarly with espacement. The mean diameter of live branches was not significantly affected by espacement.

The volume of occluded branches in trees at 1.7 m spacing was significantly less than that in trees at the wider spacings, though there was no difference in this characteristic between the wider spacings, i.e. from 2.4 m to 6.9 m. The same conclusion applied to the relationship between mean diameter of the knotty core and espacement.

The cross-sectional area affected by wood-rotting fungi was found to be lowest for the 1.7 m espacement. However, when the area affected by rot was expressed as a proportion of the cross-sectional area of the stem all espacements were affected similarly. Occluding branches were observed to be the origin of the rot.