Environmental weed invasions on south-east Queensland foredunes.
A study was performed in 1996 and 1997 along the subtropical southeast (SE) coast of Queensland, Australia, from Coolangatta (Gold Coast) to Noosa National Park (Sunshine Coast). Naturalized vascular alien plants comprised 157 species (59% of total SE Queensland foredune flora) belonging to 54 families and 122 genera. The most successful 'weedy' families were Poaceae, Asteraceae and Fabaceae. Herbaceous life-forms and succulents were found dominating the understorey strata. Most invasive species were either ornamental garden plants or economic agricultural plants. The most invasive seashore weeds were Asparagus aethiopicus cv. Sprengeri, Bryophyllum spp., Chrysanthemoides monilifera [C. moniliferum] subsp. rotundata, Gloriosa superba, Lantana camara, Panicum maximum, Schefflera actinophylla, Schinus terebinthifolia [S. terebinthifolius], Senna pendula var. glabrata and Wedelia trilobata. A temporal study along the Sunshine Coast, between 1982 and 1997, recorded 5 new weedy species per year naturalizing in the study area. Many of these new weed introductions may have occurred as 'sleeper' populations that existed in the area for a time before becoming pests. Species composition, species richness and vegetation structure are viewed in terms of succession. The dumping of garden waste adjacent to and in native vegetation within a distance of 500 m of housing was a major source of weed introductions. To prevent further weed invasion into native beachfront vegetation, urgent action is required, such as early detection and follow-up eradication. Education of coastal dwellers is required to discourage dumping of garden refuse into nearby native vegetation. Local authorities are responsible for the conditions of the seashore vegetation and as a result are encouraged to maintain a conservation ethic of protecting the natural environment.