Experiences in utilising hardwood plantation timbers

Over the past 20 years, Australia has become very dependent on its developing softwood plantation resource, which now provides close to 60% of the total sawn products and all of the panel products manufactured in the country and will expand by about 40% over the next ten years. The hardwood industry is going through considerable change, having to find new markets, after being displaced from its traditonal markets by the more efficient softwood industry and having to adapt to a younger and lower quality regrowth resource. The technology which is being put in place by the hardwood industry is showing that it can be readily adapted to handling similar-sized logs from short-rotation, however the wood quality characteristics can be quite different. Plantation-grown trees are showing a much larger corewood zone, consisting of low-density juvenile wood and the knotty core. The wood is usually lighter in colour, containing less extractive, is less durable and also is not as stable in end-use as mature wood of the same species. Sawing young, fast-grown eucalyptus in Australia does present increased problems with growth stress and reduced range of product dimensions, but through the development of modified sawing systems and the adoption of training programs, it has been possible to maintain sawn recovery and productivity. The potential of hardwood plantations has yet to be realised. Improved resource availability, tree growth and processing will encourage large-scale investment in hardwoods. For many end-users, the lower-density wood is of more value, being more readily stained to end-users requirement and easier to machine and to laminate into larger than components. although residue quantities may be substantially greater than from natural forests, it can be of premium quality for the pulp and paper industry. The domestication of hardwood is still very much in the early phase. It will take many years of concerted effort to screen the many potential species available and an integrated effort between geneticists, silviculturists and wood scientists to ensure growth and wood quality targets can be clearly identified and achieved.