Scientists plant new generation of elms - with fingers crossed

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The Independent Online

A national project to restore the English elm to the countryside will next month plant its first saplings in the wild, 30 years after the species was almost wiped out by Dutch elm disease.

A national project to restore the English elm to the countryside will next month plant its first saplings in the wild, 30 years after the species was almost wiped out by Dutch elm disease.

Several hundred saplings taken from elms that survived the disease in the late 1960s and 1970s will be planted in the hope that a new generation of disease-resistant elms will re-establish one of the nation's best-loved trees.

Dutch Elm disease killed some 25 million elms in the United Kingdom but despite widespread public assumption that the disease eliminated the tree altogether, some five million remain.

The National Elm Programme has taken cuttings from those elms that are more than 60 years old in the hope that they possess a genetic predisposition that enabled them to resist the fungus.

The programme is being run by the Conservation Foundation, an environmental charity, with support from the Forestry Commission, the leading organisation monitoring the effects of Dutch elm disease since it first appeared in Britain. While there have been small-scale, localised attempts to replant elm trees before, this project, which has commercial funding, is the first on a national scale. Several hundred saplings, currently being grown in a nursery in Bedfordshire, will be handed to farmers and local wildlife groups to plant in the countryside. The fledgling trees will be closely monitored in coming years for any signs of disease.

"It's a long-term thing," said David Shreeve, who co-founded the Conservation Foundation with the ecologist David Bellamy. "We lost 25 million elms, so there's a fair few to replace. We hope the saplings we have are from trees which through a quirk of fate were resistant to the disease. Rather than give up and forget the elm we think it's worth a try.

"The heritage of the English elm is tremendous. It was a landmark feature of the countryside, forming hedgerows and feeding cattle; its wood was used for coffins for dead farmers. If the elms recover, the farmers may not live to see them grow but their children will have the chance to see the elm back in its rightful place."

The move comes as fresh outbreaks of the disease serve as a salutary reminder that the fungus has not gone away. In Edinburgh, one of a handful of British cities still to boast a significant elm population there was a 33 per cent rise in the number of elm trees felled in the three years to December 1999, compared with the previous three-year period. A thousand are dying each year. "We have a vigorous programme of replanting and are quick to identify the disease," said a spokeswoman for the city council, which spends £500,000 every year on felling diseased elms. "We can contain the disease but it will continue to spread. We cannot eradicate it."

In Warwickshire, one of the counties hit hardest by the disease the first time around, 36 dead elm trees have just been removed from Charlecote Park in Stratford-upon-Avon. At Coughton Court, near Alcester, where a renowned avenue of elms was destroyed by the disease in the 1970s, many of the elms that survived then have now died.

The virulent strain of Dutch elm disease is thought to have arrived from the United States in 1968, carried in a shipload of bark and logs by the flying scolytus beetle. The beetle lays its eggs in the bark of elms that are freshly dead or dying from the disease. After hatching, the new young beetles pick up the fungus spores on their body surfaces, then fly to healthy elm trees to feed, infecting the healthy trees in the process. The more trees that are killed, the more breeding material there is available for the beetles.

Conservationists and scientists have few remedies available. Many councils and park managers simply cut and burn elms at the first sign of the disease. A fungicide can offer up to 75 per cent protection but because it is expensive and difficult to administer correctly it is only used for elm trees of great public value, such as those in country parks. Another option is to hope that nature will do the work for the scientists: a naturally occurring virus in the bark of some elm trees may reduce the ability of the fungus to cause damage to the tree. Other elms which have been trimmed into hedges have survived because the beetle tends to target large trees that are highly visible. Gloucestershire, where this type of landscaping is popular, has a large number of healthy elm trees.

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