Influence of dose, bark cover and end-grain sealing on ethanedinitrile (C2N2) sorption by pine (Pinus radiata D. Don) logs

Abstract

High sorption by Pinus radiata (D. Don) logs may limit insecticidal efficacy of a fumigant by rapidly removing it from the treated headspace. The sorption characteristics of a new fumigant, ethanedinitrile (EDN), were quantified for recently harvested pine logs, and the robustness of a proposed EDN sorption model developed for sawn timber was tested. Over a 10-h period, average concentrations were 17.3% ± 0.7 of the initial dose for logs with sealed ends and 9.4% ± 0.4 for unsealed ends. This is a high rate of sorption compared with other fumigants, such as methyl bromide. A proportional drop in headspace concentration over time was consistent for the two doses (20 and 50 g/m3) evaluated, confirming that EDN sorption is influenced by the dose applied. Bark cover did not significantly influence EDN sorption. A revised sorption model for EDN is proposed here.