Laboratory and marine trials of resistance of furfurylated wood to marine borers

New approaches are needed to prevent borer attack in wood intended for use in the marine environment, because traditional treatments are restricted or prohibited in this end use. Wood modification is a promising alternative, but the modification processes may require optimisation for marine end use. The standard testing method as defined by EN275 requires long term marine testing in which an iterative approach to process refinement is not feasible. This study used rapid laboratory testing protocols and marine tests to evaluate the efficacy of furfurylation in reducing attack by marine wood borers. Laboratory trials provided rapid assessment of potential treatments under controlled conditions, whilst marine trials provide more robust long term results under realistic exposure conditions. The wood samples were treated with one of three proprietary procedures for inducing polymerisation. Established methods for testing with the boring crustacean Limnoria allowed comparisons to be made with known timber species with a reputation for durability under marine conditions. Wood modification was shown to achieve useful reductions in feeding rate and survival of test organisms. Statistically robust results were obtained within four weeks. New methods for assessing the effects of wood modification on settlement and subsequent grown by shipworms yielded similarly robust and rapid results. The findings were compared with data for the same wood modifications obtained in a standard marine trial. Field and laboratory findings were in broad agreement. The laboratory methods were shown to be suitable for iterative optimisation of modification.