This investigation sought to determine the potential of selected NZ staining fungi to induce weight loss and changes in toughness (impact bending strength) and composition in unseasoned radiata pine sapwood. Furthermore, assays were performed to eveluate enzyme production by staining fungi. Sets of side-matched specimens were inoculated with Ophiostoma floccosum, Sphaeropsis sapinea and O. pluriannulatum prior to 8 and 16 weeks incubation, along with non-inoculated control samples. After incubation, samples were equilibrated to 14% wood moisture content before determining toughness and weight loss.Neither nor dry weight were significantly different (p <0.05) between inoculated samples and controls, irrespective of sapstain fungi used. Quantitative chemical analysis showed that there was no significant difference between the lignin and carbohydrate composition of inoculated samples and controls. Enzyme assays demonstrated that all staining fungi tested produced xylanase, but carboxymethylcellulase was not detected. Xylanase values range between 0.07 µ moles/min/ml and 0.66 µ moles/min/ml depending on the fungus tested. Thus we conclude that the New Zealand staining fungi under test, though they produce a slight amount of an hemicellulolytic enzyme, do not degrade radiata pine.

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