Most Unwanted: Giant Salvinia
Salvinia molesta
Habitat: Freshwater
Threat: Clogs waterways and negatively impacts on native species and ecosystems
Status: Potential
Salvina molesta is an aquatic species that has become invasive in a number of different areas around the world. This is a species that has raised concern in Ireland as climate change may lead to the risk of establishment in the wild.
What is it?
Free floating aquatic fern with fronds arranged in whorls of three (two floating and one submerged). The floating fronds are positioned in an opposite orientation to each other and are round to oblong in shape. The fronds are light to medium green, often with brownish edges in mature plants, and with a distinctive fold in the centre.
Impact
Salvinia molesta, one of the world’s most noxious aquatic weeds, is notorious for dominating slow moving freshwaters. Its rapid growth, vegetative reproduction and tolerance to environmental stress make it an aggressive, competitive species known to impact aquatic environments, water use and local economies.
Habitat
Lakes and ponds, ditches, slow flowing streams and rivers.
Where is it from?
Native to Brazil and Argentina
Where is it now?
Africa, Asia (in India), the Australasia-Pacific region and, more recently, the USA.
How can it get here?
Garden plant trade.
What you can do to prevent its arrival
Do not buy any invasive aquatic plants. Consider native species as an alternative
If you are a garden centre manager remove Salvinia from sale.
Never dispose of garden or aquarium waste near waterways.
Report all sightings.
Additional information
Nonindigenous Aquatic Ferns
in the United States
Salvinia molesta - Salvinia minima
