Scientific Mystery Solved As Rare Tresco Plant Identified

murphys threadwortAn extremely rare plant that was first discovered on Tresco in the 60’s and had scientists scratching their heads for decades has finally been identified – as a New Zealand stowaway.

The tiny Murphy’s threadwort was first spotted near the Abbey Gardens in 1961, although it’s since been found on St Mary’s, at the Lower Moors and in a Hugh Town garden.

There are only two other sites in the UK where it grows – in Poole and Bournemouth.

It’s always been known that it wasn’t a native plant, but now scientists have used the latest DNA technology to discover its origins.

And one of the team, Dr Laura Forrest from the Royal Botanic Gardens in Edinburgh, says it matches a species called Long’s threadwort that grows in the South Island of New Zealand.

She says it’s likely it arrived here on tree ferns, imported in large numbers by the Victorians.

Laura says it’s an important finding because it solves the mystery about where it comes from. And it also clears up a debate about whether it should be protected or not.

It was put on the UK’s botanical ‘red list’ of very rare plants, because of its unique characteristics. That means it had to be conserved until its real origins could be found.

But at the same time, it wasn’t part of any botanical protection programmes because it wasn’t a native plant.

It’s still quite rare in its home country, so it’s the Kiwis who will now have to protect the species. It’s also likely to receive a name change here.

Even though it’s an invader, Laura says our plant is a ‘male’ version of the species, so can’t spread long distances by producing spores. That means it shouldn’t cause any problems to the native plants.

And she says that while it’s brought many scientists here over the years, the tiny plant is unlikely to be a big tourist attraction.

The DNA testing has turned up another unexpected finding. The ‘female’ version of the plant, which looks very different, has actually been growing at the Benmore Botanical Garden in Scotland for decades.