Aquatic Weeds

Queensland Aquatic Weeds

The three most problematic aquatic weeds we encounter are -


Salvinia (Salvinia molesta) is a free floating aquatic weed native to South America. It was introduced to Australia as an ornamental plant for ponds and aquariums. It survives in still and slow moving waterbodies with salinities up to 7ppt. During optimum growth conditions these plant can double its size in 5-10 days. This rapid growth out competes native species. Untreated infestations can completely smother and choke waterways. Salvinia propagates from fragmentation of the parent plant and regeneration from the nodes. Salvinia molesta is a declared Class 2 species under the Land Protection (Pest and Stock Route Management) Act 2002. Control is required by landowners.


Water Hyacinth (Eichhornia crassipes) is another aquatic free floating weed native to South America that infests still and slow moving freshwater bodies. Uncontrolled this weed can completely cover waterways and dams. Combining the large amount of organic matter produced and the lack of sunlight and oxygen able to reach the surface of the water the system is starved of dissolved oxygen. Without oxygen much of the native aquatic life cannot survive. Water Hyacinth reproduces via seeds that sink to the bottom. Eichhornia crassipes is a declared Class 2 species under the Land Protection (Pest and Stock Route Management) Act 2002. The control of declared pests is required by landholders.


Cabomba (Cabomba caroliniana) is a weed of National Significance. It is regarded as one of Australia?s worst weeds due invasiveness, economic and environmental impacts. It is a submerged aquatic weed that produces vast amounts of submerged plant matter. It was introduced for use as an ornamental plant for aquariums. Cabomba can reduce water storage capacities and choke water bodies excluding native species. The weed can be identified by the segmented braches of fanlike feathery leaves and small white flowers which stand above the waters surface.