 When population-level properties that indicate superior competitive ability of the invading species are examined, 13–24 (42–77%) of the species are included, with the majority of species showing traits capable of modifying natural systems at both ecosystem and community/population scales.The dumping of green waste such as lawn clippings can block drainage systems which pollutes water therefore effecting water quality and the health of aquatic plants and animals.Dumped garden waste can add high levels of sediments, reducing the light available for photosynthesis.