This popular pond plant, originally native only to North and Central America, is also known as Fairy Fern.
There’s certainly nothing delicate about this floating nuisance though, which forms dense mats of vegetation on the water’s surface that pose a hazard by appearing solid.
Able to withstand British winters and invade a region very rapidly, this innocent sounding plant has dominated many waterways in its time, such as the Kennet & Avon Canal. Water fern spreads like a sponge across the water, reducing light beneath the surface and shading out other native plants, as well as causing de-oxygenation leading to the death of fish.
The plant is entirely free-floating and so able to grow in any depths, but the water must be still or slow moving for it to properly thrive.
Last date edited: 29 July 2015