An above-ground H3 fungal field trial was installed at two sites in Australia and one in New Zealand, as well as in two Accelerated Field Simulators. The aim was to find a method that would shorten the time required for evaluating new preservatives and protection systems. One-quarter H3 retentions were installed, as first results suitable for registration occur when these reach 70% soundness. Twelve test methods were examined, some established and others developed for the project. In two methods, feeder blocks pre-inoculated with laboratory-raised fungi were placed next to test specimens in an effort to accelerate decay. The treatments examined were CCA, alkaline copper high quat (AChQ), azoles, kerosene, TBTN, and water. Untreated Corymbia maculata heartwood was included for natural durability. Inspection was annual for four years. The fastest test was the ‘rot box’ at Innisfail, followed by the ground proximity, deck-on-ground and embedded tests. The most reliable tests giving expected relative order of failure were those allowing diversity of fungi rather than those that became dominated by a few, and included those placed close-to-ground or those with increased volume of untreated wood substrate in frames. Pre-inoculation with Gloeophyllum abietinum gave more representative results than those pre-inoculated with Oligoporus placenta.
Keywords: above-ground, field testing, H3, decay, CCA, azoles, accelerated field simulator, Pinus radiata, Corymbia maculata