One of Britain's rarest and most beautiful flowers has been saved from extinction.
For the past half-century a lone Lady's-slipper orchid – or Cypripedium calceolus – has been kept under 24-hour guard at a secret location on a North Yorkshire hill – the last native plant of its kind growing outside of laboratories.
English Nature botanists announced yesterday that hundreds of plants grown in the laboratory had been successfully replanted in the wild, the culmination of 40 years' work.
By far the most brightly coloured and exotic of all British orchids, the maroon and yellow Lady's-slipper was a favourite with Victorians, who wanted them for their gardens or pressed flower collections. By the beginning of the 20th century it had been "picked to death". In the Sixties, a thief stole part of the lone wild survivor but fortunately left enough stems and roots for the plant to continue to grow.
Today it is still kept under constant guard during the months it is recognisable above ground, and has provided seeds for pollinating and propagating the orchid in the laboratory.
Ian Taylor, a botanist with English Nature, said: "By the time we got to the 1950s we were down to one plant in a locality in Yorkshire, and that plant was believed to be under considerable threat so it was guarded and highly protected from the time of its discovery through to the 1970s, when we decided we could not just sit there with just one plant in one place and do nothing about it.
"The problem was at that time we did not have techniques to extend the population. It did not flower every year but infrequently.
"A healthy population with a lot of flowers would produce vast quantities of seeds, only a few of which would survive. When you are down to one plant it does not pollinate naturally because there are too few flowers," explained Mr Taylor.
Not until the early 1990s did scientists discovered new ways to assist with wildlife reproduction. "These were called micro-propagation, which involved the production of new plants in the laboratory using seeds produced by hand-pollination and producing them in a sterile culture at Kew Gardens in London," he said.
"We had a lot of failures, a lot of problems producing viable seeds, and even bigger problems getting them back into the wild, but from about 1995-96 onwards we had worked out most of the problems."
The scientists have now succeeded in transferring the laboratory-bred plants to their natural limestone habitats, which stretch from Cumbria in the west to the North Sea coastline of Durham and Yorkshire in the east.Mr Taylor added: "We have now got 200 to 300 plants back into the wild in, I think, 12 localities across that area, the majority in North Yorkshire."
The sites are secret, though one – near the waterfall at Ingleton Glen – is on view to the public. One of the laboratory-bred plants has even flowered.
Problems still exist. The "cosseted" plants are unused to surviving in the wild and scientists continue to work on making them hardy enough to cope with pests and fungi.
But Mr Taylor is confident that years of work will eventually pay off. "It is not our intention to garden this for ever. We want to get enough plants back into the wild to be self- sustaining. But to get it through this difficult intensive-care stage may take decades."Reuse content