An above-ground H3 fungal field trial was installed at five sites (3 in Australia, 2 in New Zealand), with the aim of finding a method that would shorten the time required for evaluating new preservatives and protection systems. One-quarter of the H3 preservative retentions were mostly installed, as first results suitable for registration occur when these reach 70% soundness. Chemical analysis of spare treated specimens gave retentions that averaged 9% lower than determined by solution uptake. This paper provides the exposure results from Australia after one year. At Clayton near Melbourne, untreated Pinus radiata test specimens had highest moisture content in the ‘rot box’ design, followed by the ground proximity and ‘embedded test’, while ‘flat panels’ were driest. Most extensive decay occurred in tests where wood separators between test specimens had been pre-inoculated with Gloeophyllum abietinum (brown rot) or Perenniporia tephropora (white rot). At Innisfail in frames not intentionally pre-inoculated, water-treated P. radiata was extensively decayed when ‘flat panels’ were placed on an aged test frame. Minor decay to water-treated P. radiata occurred in the ground proximity, deck-on-ground and rot box tests. In comparison, no decay was found in the embedded, flat panel (new frame), raised deck, modified double layer and peg tests. The treatments under test included CCA, copper chromate, alkaline copper high quat (AChQ), copper azole, azoles, kerosene, boron, TBTN, and copper naphthenate. Untreated Corymbia maculata heartwood was included as an example for natural durability.

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