Flowers come out as ‘rarest tree’ beats extinction

Desperate efforts to save St Helena’s bastard gumwood tree are bearing fruit – or rather, flowers.

Dr Phil Lambdon and his team had to delicately pick up pollen grains with brushes and “paint” them on to blossom of the only known surviving tree.

Only one in every ten thousand pollen grains was thought likely to germinate.

But five young plants have now flowered for the first time as a result of the rescue operation, according to an updated version of St Helena’s first State of the Environment report.

In 2009, the lone tree at Pounceys was encased in a case of mesh to stop insects landing on it with pollen from nearby false gumwood trees – which would have resulted in impure hybrids.

Only if pure plants could be raised would the species be saved from extinction.

It had already been officially declared extinct in the wild, because the trees at Pounceys had been planted there in the endemics nursery.

But after the rescue mission began in 2009, a surviving wild tree was found growing on a remote cliff.

That brought hopes of raising new trees with a healthy mix of genes.

In fact, the bastard gumwood was already thought to have been lost once before. 

In 1868, only a single specimen of the species was known, at Black Field in Longwood. And when it died, the species – unique to St Helena – was thought to be extinct.

But in 1982, another single tree was discovered by Stedson Stroud, growing out of a cliff close to Horse Pasture.

That tree died in August 1986, but a cutting and at least 19 seedlings were successfully raised at Pounceys, near St Paul’s Cathedral.

But conservationists struggled to get them to produce viable seedlings.

Gradually, all but one of them died off, and Dr Phil Lambdon’s rescue effort was launched with funding from the UK government.

The situation was made more desperate because the tree’s seeds have an in-built resistance to its own pollen.

Insects were even captured in areas where the false gumwood did not grow, and let into the protective cage to increase chances of pollination.

By 2011, some 200 seedlings were ready to be planted out on land provided by St Helena National Trust.

The story of the mission’s success – so far – appears in the new version of the State of the Environment Report.

It says: “Bastard Gumwood have temporarily been brought from the brink of extinction: from two lone survivors which gave poor seed set, with average germination of 0.001%.

“The first five plants from this programme have now flowered for the first time.

“Seed set has improved and an average germination of 1% has been achieved, giving a 1000% increase in viability.”

A report on the UK Overseas Territories Conservation Forum website tells how planting bastard gumwoods on High Hill is helping to recreate St Helena’s depleted cloud forest.

It says they could help encourage rainfall on the island, just as tourism is set to increase demand for water.

SEE ALSO:
Island’s large bellflower ‘could be lost’ to genetic mix-up
New books on St Helena plant life – launching July 2013

LINKS:
Fight to save dying plants speciesBBC story and pictures on bastard gumwood
Queen presents MBE to Stedson

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