Water hyacinth
Eichhornia crassipes
family
Pontederiaceae
origin
Exotic
declaration
Category 3 Restricted Matter (Biosecurity Act 2014)
Must not be distributed or disposed. This means it must not be released into the environment unless the distribution or disposal is authorised in a regulation or under a permit.
Common names
Lilac devil, Nile lily, Pickerelweed, Water orchid.
A very distinctive free-floating plant that produces runners across the water surface which give rise to new plants. It develops rosettes of buoyant glossy leaves that usually have inflated leaf stalks and oval to rounded leaf blades. Its showy purple to mauve flowers (4-6 cm long and 3.5-5 cm wide) are borne in spikes at the top of upright flowering stems. These flowers have six broad 'petals', the uppermost of which has a large yellow spot. Its fruiting capsules (10-15 mm long) release their seeds below the water surface.
Impact
Impact
Water hyacinth (Eichhornia crassipes) is regarded as a significant environmental weed in the Northern Territory, Western Australia, Queensland, New South Wales and the ACT. It is also regarded as an environmental weed in South Australia and Victoria. This species is one of the most invasive plants in the world, being listed in the Global Invasive Species Database among the top 100 of the world€™s worst invasive alien species, and it is the most serious weed in many tropical, sub-tropical and warmer temperate freshwater habitats worldwide. It was recently also listed as a priority environmental weed in two Natural Resource Management regions in Australia, even though a successful biological control program has significantly reduced its impact in this country.The free-floating nature of water hyacinth (Eichhornia crassipes) means that it can quickly and easily spread throughout an aquatic ecosystem. Its high seed production and its ability to reproduce vegetatively at a rapid rate is vital to its success as a weed, and in good conditions it is capable of doubling its population in less than ten days. Dense carpets of this species can alter the ecology of the infested area as native plants, birds and fish are killed or displaced. In slow-moving and still waterbodies it is especially problematic as the dense monospecific mats of vegetation lower dissolved oxygen levels in the water, shade out native submersed plant species, alter river hydrology and increase organic sediment.Despite the significant effect of biocontrol agents, water hyacinth (Eichhornia crassipes) is still a significant environmental weed in northern and eastern Australia. For example, it was recently ranked among the top 20 most invasive plant species in the south-eastern Queensland region. It also causes significant problems in the southern parts of Australia, where growth is less vigorous but biocontrol agents are also less effective. For example, water hyacinth (Eichhornia crassipes) is a rampant weed of open water in the Gwydir Wetlands in inland New South Wales, and quickly spreads in areas that are inundated for long periods.
Location
Location
Characteristics
Characteristics
Similar Species
Similar Species
Water hyacinth (Eichhornia crassipes) is regarded as a significant environmental weed in the Northern Territory, Western Australia, Queensland, New South Wales and the ACT. It is also regarded as an environmental weed in South Australia and Victoria. This species is one of the most invasive plants in the world, being listed in the Global Invasive Species Database among the top 100 of the world€™s worst invasive alien species, and it is the most serious weed in many tropical, sub-tropical and warmer temperate freshwater habitats worldwide. It was recently also listed as a priority environmental weed in two Natural Resource Management regions in Australia, even though a successful biological control program has significantly reduced its impact in this country.The free-floating nature of water hyacinth (Eichhornia crassipes) means that it can quickly and easily spread throughout an aquatic ecosystem. Its high seed production and its ability to reproduce vegetatively at a rapid rate is vital to its success as a weed, and in good conditions it is capable of doubling its population in less than ten days. Dense carpets of this species can alter the ecology of the infested area as native plants, birds and fish are killed or displaced. In slow-moving and still waterbodies it is especially problematic as the dense monospecific mats of vegetation lower dissolved oxygen levels in the water, shade out native submersed plant species, alter river hydrology and increase organic sediment.Despite the significant effect of biocontrol agents, water hyacinth (Eichhornia crassipes) is still a significant environmental weed in northern and eastern Australia. For example, it was recently ranked among the top 20 most invasive plant species in the south-eastern Queensland region. It also causes significant problems in the southern parts of Australia, where growth is less vigorous but biocontrol agents are also less effective. For example, water hyacinth (Eichhornia crassipes) is a rampant weed of open water in the Gwydir Wetlands in inland New South Wales, and quickly spreads in areas that are inundated for long periods.
