The fungicidal and termiticidal effectiveness of a new rod form of diffusible remedial wood preservative, containing disodium octaborate tetrahydrate/sodium fluoride and marketed as Polesaver Rod, was evaluated in laboratory tests against three species of basidiomycete fungi (Coniophora olivacea, Pycnoporus coccineus, Perenniporia tephropora) and two species of subterranean termites (Coptotermes acinaciformis, Mastotermes darwiniensis). The rods were dissolved in water and various dilutions were used to treat specimens of Eucalyptus regnans sapwood using a full-cell process, providing retention levels which ranged from 1.2 to 37.4 kg/m³. Soil jar decay tests have shown the remedial preservative is toxic to Coniophora olivacea and Pycnoporus coccineus at a retention of 1.2 kg/m³ solubilised total rod and 2.3 kg/m³ for Perenniporia tephropora. Mean% mass loss data showed that a retention between 2.3 and 4.7 kg/m³ was necessary to protect specimens from significant attack by Coptotermes acinaciformis and between 9.3 and 18.7 kg/m³ for the more voracious Mastotermes darwiniensis. Laboratory diffusion tests on several species of eucalypt hardwoods have confirmed the capability of the preservative's active ingredients to diffuse through both heartwood and sapwood in concentrations toxic enough to inhibit fungal growth. In addition, field testing has shown that after eight months, significant radial and longitudinal diffusion of boron and fluorine was achieved from rods introduced into Eucalyptus obliqua pole stubs. Samples taken within the diffusion zone indicated loadings of up to 4.1 kg/m³ of boron and 5.2 kg/m³ of fluoride.

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