Does smoke derived from Victorian native vegetation stimulate germination of dormant soil-stored seed?

Abstract

The effectiveness of Victorian (local) plant-derived smoke in stimulating germination of soil-stored seeds was compared with that of commercial sources from Western Australia and South Africa, for soil samples from a Eucalyptus baxteri (Bentham) Maiden and Blakely ex. J. Black heathy-woodland in the Grampians National Park, western Victoria, using a glasshouse experiment. Smoke from all three sources enhanced seedling emergence relative to no treatment (control). Seedling densities for the Victorian and Western Australian smoke treatments were not significantly different, but were higher than those for the South African smoke. There were also significant differences in species richness and composition among smoke treatments. Mean richness was highest in the Western Australian and lowest in the South African smoke treatments. Differences in species composition were again greatest between samples treated with Victorian or Western Australian smoke and those treated with South African smoke. Smoke clearly acts as a trigger for germination in some species. However, comparisons here were complicated by different methods of smoke production. Further research is required to identify the chemical constituents of smoke which influence seed germination, and the optimum concentration(s) of smoke in relation to germination