Assessment of invasive naturalized plants in south-east Queensland.
A list of 200 invasive naturalized species was prepared as a working document for the compilation of an environmental weed list for south-east Queensland, Australia. Species were selected from the 1060 naturalized taxa and were ranked based upon invasiveness and frequency in non-agricultural areas and/or remnant natural areas. The list was compiled using records of 1413 vegetation sites, 10 163 herbarium specimens and ranking scores of thirteen members of an expert assessment panel. One third of the 200 species listed were categorized as highly invasive. Ninety percent were intentionally introduced for landscaping, agriculture and aquariums. One half of the list consist of herbs, including 34 species (17%) of grasses and 19 species (9%) of aquatic weeds. Woody weeds (shrubs and trees) are a problem in south-east Queensland, representing 37% (75 species). The ten highest ranked invasive species in descending order were lantana (Lantana camara), groundsel bush (Baccharis halimifolia), mother-of-millions (Bryophyllum delagoense), cat's claw creeper (Macfadyena unguis-cati), Madeira vine (Anredera cordifolia), ornamental asparagus (Asparagus africanus), Chinese celtis (Celtis sinensis), camphor laurel (Cinnamomum camphora), broad-leaf pepper tree (Schinus terebinthifolius) and salvinia (Salvinia molesta).