A plant so rare in the UK that it was only found in a patch smaller than a doormat has been reintroduced near the banks of the river Arun where it once thrived over a hundred years ago.
A total of 400 triangular club-rushes have been planted over an area of 20 square metres which will be managed by WWT at Arundel Wetland Centre to reverse the hands of time and encourage the shrub to seed. The hope is that it will spread and colonise some of its old haunts close to the Arun estuary.
The critically endangered schoenoplectus triqueter has always been rare in the UK, restricted to a few estuaries along the south coast of England. This perennial sedge is recognisable by its bright green, three-angled stems reaching a height of 150cm with its humble brown flowers blooming in mid-summer.
Centre Manager at WWT Arundel Paul Stevens said:
“We’re thrilled to welcome this rare plant back to Arundel, where it belongs. We’ve planted it along our Arun Riverlife Lagoon which replicates the river’s habitats – right in the centre of our site.
“Unfortunately by the end of the 20th century this nationally rare plant was on the brink of extinction throughout the UK.
“Hopefully this is the beginning of its way-overdue comeback.”
Habitat and environmental changes along historic growing sites on the Thames, Medway and Arun meant conditions were no longer favourable for the species. While there are no firm reasons why the plant disappeared from all three sites, changes to bank structure, embankment creation and dredging is likely why it vanished from the Thames.
Eventually its presence was restricted to just a few plants covering less than the area of a front door mat on the upper reaches of the Tamar estuary at one spot along the Devon bank.
The plant has been subject to a recovery programme since the mid-nineties, bringing together various conservation organisations to try and ensure its survival.
Natural England and the Environment Agency have provided expertise and funding while commissioning Panscape, an independent consultancy, to carry out much of the fieldwork.
Initial actions identified in the UK Biodiversity Action Plan, have been refined and gradually, through trial and error, the population of the triangular club-rush has increased on the Tamar and has now been reintroduced to Arun’s riverside.
In the mid 1990’s, a shoot from the triangular club-rush was taken from the Tamar to be cultivated at Wakehurst Botanic Gardens in West Sussex. The site, owned by the National Trust, is used and managed by the Royal Botanic Gardens, Kew for plant research and also to house the Millennium Seed Bank. This not only prevented the plant from extinction but also provided material for the Royal Botanic Gardens’ plant scientists to propagate new stock to be transplanted back to notable strongholds in and beside the Tamar estuary.
The transplants have been annually monitored by Panscape and in 2017 the native population increased from less than 0.5m at its low point in the 1990’s to an area of over 80 square metres with many plants successfully flowering and producing viable seed.
Natural England and WWT began talks to bring the plant to Arundel in 2017 and in spring, a suitable spot was selected.
Visitors to the centre will be able to view this incredibly rare plant, which will hopefully prosper in its historic home.