An accelerated field simulator for aboveground testing of wood preservatives

The wood preservation industry in Canada is interested in new preservatives, some of which are intended only for above-ground uses. Canada's Pest Management Regulatory Agency requires data from field tests under Canadian conditions but these can take many years to generate results. FPInnovations has, therefore, developed an accelerated field simulation test for above-ground applications. This paper provides examples of results on four formulations tested for one anonymous client. Short lengths of treated and untreated nominal 2 by 6s were supported on stainless steel screws and intermittently sprayed with deionized water from above. All of the test material was exposed to spores of Gloeophyllium sepiarium and Oligoporus placentus from fruiting bodies grown on Petri dishes that were Suspended from the ceiling and to spores from outside air introduced at intervals via a fan. In addition, half of the boards were exposed to mycelial colonization from wood blocks infected with G. sepiarium. The test material was evaluated using the AWPA rating system. PCR and DNA sequencing demonstrated that infection had in many cases occurred via spore germination. Two years of data suggest, at least on spruce, this new test method is capable of discriminating between treatments that may be resistant only to spore germination and those that are resistant to both spores and mycelium.