Comparative effects of different smoke treatments on germination of Australian native plants

This study consists of a series of investigations designed to determine the potential of concentrated smoke products to stimulate seed germination and assist in the rehabilitation of degraded landscapes. Aerosol smoke and conventional smoke water products are not practical for use in broad-scale seed bank regeneration programmes due to infrastructure limitations and the high rate of application required for their use. Concentrated smoke products have been found to be effective in stimulating soil seed banks and are suitable for broad-scale use due to the lower rate of application required to elicit germination within smoke-responsive species. The use of concentrated smoke products on undisturbed soil seed banks at 50 and 100 mL m(-2) increased total seedling numbers 10-fold, while species richness more than doubled over untreated controls. Although aerosol smoke applied directly to soil promoted 10 times more seedlings compared to concentrated smoke products, species richness levels in each treatment were similar. Concentrated smoke products cause leaf scorch when applied directly over plants in active growth, with limited to nil damage when plants are not actively growing. The affected plants generally recovered following application of concentrated smoke products as a foliar spray.