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Salisbury, Australia

McGavin R.L.,University of Melbourne | McGavin R.L.,Salisbury Research Facility | Bailleres H.,Salisbury Research Facility | Lane F.,Salisbury Research Facility | And 3 more authors.
BioResources | Year: 2014

The Australian hardwood plantation industry is challenged to identify profitable markets for the sale of its wood fibre. The majority of the hardwood plantations already established in Australia have been managed for the production of pulpwood; however, interest exists to identify more profitable and value-added markets. As a consequence of a predominately pulpwood-focused management regime, this plantation resource contains a range of qualities and performance. Identifying alternative processing strategies and products that suit young plantation-grown hardwoods have proved challenging, with low product recoveries and/or unmarketable products as the outcome of many studies. Simple spindleless lathe technology was used to process 918 billets from six commercially important Australian hardwood species. The study has demonstrated that the production of rotary peeled veneer is an effective method for converting plantation hardwood trees. Recovery rates significantly higher than those reported for more traditional processing techniques (e.g., sawmilling) were achieved. Veneer visually graded to industry standards exhibited favourable recoveries suitable for the manufacture of structural products. Source


Hamilton M.G.,University of Tasmania | Hamilton M.G.,National Center for Future Forest Industries | Blackburn D.P.,University of Tasmania | Blackburn D.P.,National Center for Future Forest Industries | And 9 more authors.
Annals of Forest Science | Year: 2015

Key message: High levels of percentage green veneer recovery can be obtained from temperate eucalypt plantations. Recovery traits are affected by site and log position in the stem. Of the post-felling log traits studied, out-of-roundness was the best predictor of green recovery. Context: Eucalyptus globulus and Eucalyptus nitens are widely planted in temperate regions of the globe but few studies of rotary peeling have been documented. Aims: This study aims to examine differences among sites and log positions in post-felling log traits and green veneer recovery traits and determine the extent to which log traits explain variation in recovery traits. Methods: Log traits and green rotary-peeled veneer recovery traits from six temperate eucalypt plantations were studied. Selected plantations encompassed different age, site productivity, silvicultural and species classes in south-eastern Australia. Differences in log and recovery traits among sites and between lower and upper logs were examined, as was the extent to which log traits explained variation in recovery traits. Results: Differences among sites for percentage recovered green veneer were non-significant, despite significant differences for peelable billet volume, roundup loss, residual core diameter and all post-felling log traits: small end diameter, sweep, taper, out-of-roundness, end splitting and dynamic modulus of elasticity (MOEdyn). The lower log exhibited more sweep, taper and out-of-roundness but lower MOEdyn and less recovered green veneer. Out-of-roundness was the best predictor of recovery traits (R2 = 13–21 %, P < 0.001). Conclusion: Recovered green veneer was high across all sites and log positions (78 % overall). © 2014, INRA and Springer-Verlag France. Source


Vega M.,University of Tasmania | Vega M.,National Center for Future Forest Industries | Hamilton M.G.,CSIRO | Blackburn D.P.,University of Tasmania | And 7 more authors.
Annals of Forest Science | Year: 2016

Key message: Log-end splitting is one of the single most important defects in veneer logs. We show that log-end splitting in the temperate plantation speciesEucalyptus nitensvaries across sites and within-tree log position and increases with time in storage. Context: Log-end splitting is one of the single most important defects in veneer logs because it can substantially reduce the recovery of veneer sheets. Eucalyptus nitens can develop log-end splits, but factors affecting log-end splitting in this species are not well understood. Aims: The present study aims to describe the effect of log storage and steaming on the development of log-end splitting in logs from different plantations and log positions within the tree. Methods: The study was conducted on upper and lower logs from each of 41 trees from three 20–22-year-old Tasmanian E. nitens plantations. Log-end splitting was assessed immediately after felling, after transport and storage in a log-yard, and just before peeling. A pre-peeling steam treatment was applied to half the logs. Results: Site had a significant effect on splitting, and upper logs split more than lower logs with storage. Splitting increased with tree diameter breast height (DBH), but this relationship varied with site. The most rapidly growing site had more splitting even after accounting for DBH. No significant effect of steaming was detected. Conclusion: Log-end splitting varied across sites and within-tree log position and increased with time in storage. © 2015, INRA and Springer-Verlag France. Source


McGavin R.L.,University of Melbourne | McGavin R.L.,Salisbury Research Facility | Bailleres H.,Salisbury Research Facility | Hamilton M.,University of Tasmania | And 3 more authors.
BioResources | Year: 2015

The processing of Australian plantation-grown Eucalyptus globulus and E. nitens into rotary veneer was shown to produce acceptable recoveries. Three plantation sites for each species were sampled. Silvicultural treatments (thinning and pruning) and growing environments varied between sites. Graded veneer recoveries were dominated by D-grade veneer across all six sites. Variation between the E. nitens sites was evident, with recoveries differing between sites reflecting silvicultural treatments. However, only minimal variation in recovery was shown between the E. globulus sites. The presence of similar levels of defects across all E. globulus sites indicates that the intensive silvicultural management at one site studied was not effective in the production of clear wood, and may possibly have adversely affected grade recovery. Veneer value analysis demonstrated only minimal differences between E. globulus sites. More variation was observed in the E. nitens value analysis; however, intensive silvicultural management implemented did not necessarily result in higher veneer value. Source


McGavin R.L.,University of Melbourne | McGavin R.L.,Salisbury Research Facility | Bailleres H.,Salisbury Research Facility | Lane F.,Salisbury Research Facility | And 2 more authors.
BioResources | Year: 2014

Processing Australian hardwood plantations into rotary veneer can produce more acceptable marketable product recoveries compared to traditional processing techniques (e.g. sawmilling). Veneers resulting from processing trials from six commercially important Australian hardwood species were dominated by D-grade veneer. Defects such as encased knots, gum pockets, gum veins, surface roughness, splits, bark pockets, and decay impacted the final assigned grade. Four grading scenarios were adopted. The first included a change to the grade limitations for gum pockets and gum veins, while the second investigated the potential impact of effective pruning on grade recovery. Although both scenarios individually had a positive impact on achieving higher face grade veneer qualities, the third and fourth scenarios, which combined both, had a substantial impact, with relative veneer values increasing up to 18.2% using conservative calculations (scenario three) or up to 22.6% (scenario four) where some of the upgraded veneers were further upgraded to A-grade, which attracts superior value. The total change in veneer value was found to depend on the average billet diameter unless defects other than those relating to the scenarios (gum or knots) restricted the benefit of pruning and gum upgrading. This was the case for species prone to high levels of growth stress and related defects. Source

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