Effect of pre-steaming on drying rate,wood anatomy and shrinkage of regrowth Eucalyptus pilularis Sm.

Summary The influence of pre-steaming on the drying rate, wood anatomy and shrinkage of regrowth Eucalyptus pilularis (blackbutt) was determined. Pre-steaming increased the drying rate by 7–16%. This resulted from a mobilisation and partial removal of heartwood extractives, probably allowing greater access of water molecules to cell walls, and therefore increased radial and tangential diffusion. Longitudinal permeability is unlikely to be significantly increased by pre-steaming, as tyloses appeared unaltered. Volumetric shrinkage was unchanged.The authors wish to thank K. W. Groves of the Department of Forestry, Australian National University for his comments, J. F. Marchant and R. Colley for technical assistance, and P. Lind for some of the statistical analyses. The New South Wales Timber Advisory Council Ltd provided financial support. The work reported in this paper formed part of a post-graduate research programme undertaken by the senior author at the Department of Forestry, Australian National University