This lovely plant carpets the surface of the Wye in spring and summer, creating a water garden along stretches of the meandering river. You can identify it by white flowers with a yellow base to the petals and circular leaves which float on the water. You can see large swathes of it on the river in high summer between Ross and Bigsweir. It forms part of a habitat that helps give the River Wye its Special Area of Conservation status.
Saltmarsh grass, a nationally scarce species, can be found on the muddy river banks below Brockweir, where the river is tidal. Sea aster and sea-milkwort can also be spotted along this lower stretch of the river. At Tintern, where tidal reeds grow on the banks marginally in salt water, the Hairy Click Beetle can be found. It only lives here and on the River Parrott on the English side of the Severn.
We have at least three species of invading plant which threaten to smother the native plant species that live along the Wye. Rivers are very good at transporting and spreading the seeds of Giant Hogweed, Japanese Knotweed and Himalayan Balsam downstream and, on the Wye, seeds can be carried upstream too by the tide. These plants rapidly suffocate native plants which leads to a loss of biodiversity. They are highly persistent and difficult to eradicate, able to grow even through concrete.
The Wye Valley AONB is working with local landowners and the local Community Council to tackle the issue of Japanese Knotweed in Tintern through a 2 year project funded by the Sustainable Development Fund (SDF). Working with the Wye and Usk Foundation, plants were treated at the end of summer 2018. Regrowth will be monitored and any remaining weed treated in the autumn of 2019.
Checking for regrowth is an important part of eradicating invasive plants. The Wye and Usk Foundation rely on anglers, walkers and owners to keep them informed of any new invasive plants. If you spot any invasive weeds, be it Giant Hogweed, Japanese Knotweed or Himalayan Balsam, please email louis@wyeuskfoundation.org to report it.