The susceptibility of oriented structural straw board (OSSB) to damage by subterranean wood-destroying and grass-feeding termites in Australia
J Hague, D Scown, J Creffield, M Neal
The field performance of untreated oriented structural straw board (OSSB) made from wheat straw was evaluated against two economically important Australian species of wood destroying subterranean termite, Coptotermes acinaciformis and Mastotermes darwiniensis, and two Australian species of grass-feeding subterranean termite, Amitermes meridionalis and Nasutitermes triodiae. Oriented strand board (OSB) made from both hardwood and softwood, and solid radiata pine sapwood, were included as reference materials. All OSSB test specimens were totally destroyed by N. triodiae. OSSB test specimens were heavily damaged by M. darwiniensis (mean loss of 75%), with half of the test specimens being totally destroyed. Approximately a third of the OSSB test specimens were consumed by C. acinaciformis, supporting previously published data for the susceptibility of OSSB against the Coptotermes genus from laboratory studies against C. formosanus. M. darwiniensis largely consumed or totally destroyed test specimens from all three of the wood-based reference samples. C. acinaciformis displayed a distinct preference for the radiata pine sapwood, with five of the six test specimens being almost totally consumed; damage to the OSB test specimens was limited. Similar limited damage was also observed in the OSB test specimens when exposed to the grass-feeding N. triodiae, but one colony of N. triodiae almost totally consumed a single radiata pine sapwood test specimen, resulting in a mean mass loss of 20% for the radiata pine sapwood test specimens. The results of the study suggest that OSSB is potentially highly susceptible to damage by at least some grass-feeding and wood destroying subterranean termite species. Furthermore, the results suggest that softwood sapwood may also potentially be susceptible to damage by at least some grass-feeding subterranean termites.