Wood is widely recognized as a valuable material, yet the natural durability of some wood species limits its use for certain outdoor purposes. For decades, a wide range of methods and chemicals have been developed to increase the resistance of wood against degrading microorganisms and termites. Preservative treatment has a long and widespread tradition in wood protection. Proper testing of the effectiveness of such preservatives is based on both lab and field trials. Cookson (2013) reported on Australia’s largest in-ground stake trial of wood preservatives. The preservatives tested include low and high temperature creosotes, PCP and various water-borne preservatives including CCA and copper chromate. The main timbers examined were sawn Pinus radiata sapwood, sawn Eucalyptus regnans heartwood, and E. regnans natural rounds (mainly sapwood). The number of treatments (preservative/retention/timber combinations) tested was 208, although not at every site. Samples were put on the field on eight sites across Australia and Papoea New Guinea. The significant amount of data necessitates a concerted approach, and therefore a statistical analysis of a selection of samples was performed: creosote (K55), PCP (5%) and CCA (Celcure A and Tanalith C) were selected using all loadings and all sites. Differences between sites, preservatives and loadings were clearly present and comprehensibly displayed in separate graphs. In addition, we attempted to calculate the Scheffer index for six different sites and linking it to failure of the samples to calculate the acceleration factors of the different sites, showing clear differences between the sites considering only low to moderate termite pressure. More work has to be done however to get a proper mapping of the SCI of Australia as well as to calculate the precise acceleration factors. In all, re-analysis of such datasets is invaluable.

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