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Abstract Smoke, canopy-derived mulch, and broadcast seeds were used to maximize the establishment of Banksia woodland species in sand quarries in Western Australia. Smoke, particularly aerosol smoke, had a positive effect on total seedling recruitment. Pre-mined (woodland) sites showed a 42-fold increase in total germinants and a 3-fold increase in the number of species with aerosol smoke application. Post-mined (restored) sites showed only a 3.6-fold increase in total germinants and a 1.4-fold increase in the number of species. Two water-based smoke chemicals, DC10 (pH 4.5) and SC63 (pH 2.5), increased seedling recruitment at both sites but were not as effective in stimulating recruitment as aerosol smoke. Neither of the chemicals were effective in significantly increasing species richness. Application of aerosol smoke directly to seeds as a pretreatment before broadcasting had no effect on seedling recruitment. Broadcasting of seeds onto restoration sites significantly increased seedling abundance and richness. Application of a single layer of mulch from the canopy vegetation after seed broadcasting gave optimum seedling recruitment. Two layers of mulch significantly reduced recruitment, as did applying mulch before seed broadcasting. For broad-scale restoration, the application of smoke on newly restored sites would be more effectively achieved using smoke water sprayed over the soil surface. Species that do not recruit from replaced topsoil could be effectively recovered from broadcast seed rather than from mulch. [ABSTRACT FROM AUTHOR]

Despite being considered a major hospital-associated pathogen for many years, Clostridium difficile has been isolated increasingly from people without hospital contact. In this study, we investigated the prevalence of C. difficile in the immediate outdoor environment of several hospitals in Perth, Western Australia, to provide further insight into potential sources of community-acquired C. difficile infection. Over 6 months, a total of 159 samples consisting of soil, mulch, lawn and sand were collected from outdoor surroundings of four different old (age>50 years) and new (age<10 years) hospitals. Samples were cultured in a C. difficile selective enrichment broth. Toxin gene profiling using PCR, and PCR ribotyping, was performed on all C. difficile recovered. C. difficile was isolated from 96 of the 159 samples (60.4%). Of the 112 isolates, 33 (29.5%) were toxigenic and 49 (43.8%) were identified as novel strains. Ribotypes (RTs) 014/020 (14.3%) and 010 (13.4%) constituted the highest proportion of isolates. Interestingly, RT 017, a strain endemic to the Asia-Pacific region (but not Australia), was found in a newly laid lawn. This study adds to existing knowledge of potential sources of C. difficile in Western Australia. More research is required to determine the route of transmission of C. difficile from community sources into the hospital. • The immediate external environment of hospitals can be contaminated with C. difficile. • 60.4% of samples (consisting of soil, sand, mulch and lawn) contained C. difficile. • Ribotypes 014/020 (toxigenic) and 010 (non-toxigenic) were most frequently recovered. • Unusually, ribotype 017 was isolated from one of the new lawns sampled. [ABSTRACT FROM AUTHOR]