The beetle that is destroying Britain's landscape

Press, 17 November 1976, Page 25

The beetle that is destroying Britain's landscape

Less than ten years ago. 23 million elms flourished south of a line from Birmingham to The Wash. But figures just issued by the Forestry Commission show that another million .trees have been stricken since last autumn, bring■ng the total to nine million elms killed since the Dutch elm diseases began in Britain. “In other words,” says Mr Ken Davis, secretary of the Tree Council, “we have lost more than a third of ail the elms in central and southern England.” The Tree Council gloomily predicts that by 1980 at least half the elms in the southern part of Britain will have been wiped out. And hopes of survival for the remainder are slim indeed, resting on the .discovery of a miracle cure, or a severe winter, to stop the disease in its tracks. Like an arboreal Black Death, the disease kills every elm it touches. And like the Plague, which arrived on the back of the black rat, Dutch elm disease has its Trojan horse — a small beetle with a double-barrelled name, Scolytus scolytus, which lays its eggs under the bark of decaying elms. The grubs tunnel under the bark (lift a flake from any infected elm and you will see their maze of gal-

leries) and pick up tne spores of a poisonous fungus. Ceratocystis ulmi. In spring the adult beetles emerge and fly to neighbouring healthy trees, carrying the deadly fungus with them ' Once established, the fungus rapidly multiples. The tree fights back by producing anti-bodies. Unfortunately these gummy substances block the vital sap arteries. Result: a massive self-induced

“coronary” from which the stricken elm never recovers. The first sign of trouble is a branch suddenly turning sickly yellow. As the pestilence takes hold the whole tree yellow’s, leaves shrivel and fall, and an elm which may have taken a hundred years to reach maturity can be dead within the space of a single summer. No-one seems sure where the disease originated, but its identity was established 50 years ago by the Dutch; hence its name. Imported to North

America in logs from central Europe, it raged for two decades, and then died down. Then, in the late 19605, a newer and infinitely more virulent strain appeared. Since then it has stalked unchecked across the American continent from the Atlantic to the Rockies, killing 400,000 trees a year. And it quickly leapfrogged the Atlantic to scorch through France, Italy. Germany, the Netherlands, Belgium, and Scandinavia. Already, Paris has lost most of the 20.000 elms that graced its squares and boulevards. Forestry Commission sleuths have traced Britain’s own Dutch elm disaster to shiploads of unsawn Canadian rock elm entering Britain at Southampton, Tilbury, and Avonmouth — bridgeheads from w’hich the invasion spread at alarming speed. A single giant elm can become a crawling tenement for 200,000 beetles. By 1970 Dutch elm disease had become a matter for public concern. In 1971, when it was recognised as a far deadlier strain than anything known before, New Scientist complained that the Forestry Commission and the Ministry of Agriculture had failed to take the outbreak seriously, and had lost the chance to

avert “the oiggest single disaster to hit the Engl sn landscape for venerations.” In an attempt to establish a cordon sanitaire, the Forestry Commission had recommended a compulsory felling programme in infected areas. The order finally came into force in October 1971, but within 14 months the Ministry of Agriculture had revoked it. This was, in effect, total surrender — an admission that too little had been done too late. The battle was already lost. “The Government was just too damned mean to spend enough money to nip the thing in the bud,” says Fionn HolfordWalker, secretary of the Council for the Protection of Rural England. “They just hoped a hard winter would come along and stop the disease for them.'” But there was no hard winter, and the elms went on dying. Wiltshire’s total of stricken trees rose from 4000 in 1971 to nearly 300,000 in 1975. In Gloucestershire, 75 per cent were reported dead or dving by the middle of 1974. Meanwhile, lorry-loads of infected timber were still being freely trundled around the country, bringing fresh outbreaks to

areas hitherto uncontaminated. Not, until February, 1974, after much prodding by tire Forestry Commission and the Association of British Tree Surgeons and Arborists, did the Ministry of Agriculture ban the movement of diseased timber into “clean” areas, at the same time reintroducing compulsory felling in lightlyinfected zones. If the Government's handling of the disaster was half-baked the response of most local authorities has been pathetic. Of 332 English district councils, less than three dozen have any positive elm protection policy. A clear illustration of what might have been achieved can be seen in Sussex, which is run by two councils, East and West. In West Sussex, which made little or no attempt to contain the disease, more than 80,000 out of a total of 91,000 elms are now either dead or dying. But neighbouring East Sussex is a different story. “We decided to right Dutch elm d'sease from the moment we discovered the first infected tree,” says Tony Denyer, the council’s e’m disease officer. As a result East Sussex has lost only one in ten of its elm«. Elsewhere the tragedy continues. London's royal parks used to contain more than 8000 elms. Now only 3000 are still standing and nearly half of these are sickly. Among the latest victims are the pleached elms o 1 Queen Mary’s Bower at Hampton Court — felled four weeks ago and due to be replaced with hornbeams. The Forestry Commission reckons tnat removing all the dangerous, dead hulks from the landscape could cost the nation at least SBS million over the next five years. Felling costs vary enormously, depending upon the state of the tree and its situation. “Anything from $5 to $500,” says the Tree Council. Once felled, though, the trees are a potential source of good hardwood timber. Although the bark is ravaged, the wood is usually sound. The trouble

is that Britain now has a timber mountain. “There is too much elm chasing too few outlets,” says Geoffrey. Agate, chairman of the Elm Marketing Group. The E.M.G. is an ad hoc body formed by the Forestry Commission and the timber trade. Its purpose is to dream up new uses for the unprofitable elm. “We want to create more outlets so that people will have an incentive to clear dead trees from their land,” says Mr Agate. “Then, instead of costing money to cut down dead elms, they may even begin to make a small profit.” Traditionally, much me-dium-quality elm has been used down the pits. Elm is also enjoying a bit of a comeback in another oldestablished market — the coffin trade. But the E.M.G. is pressing for a wider application of elm in situations where its water-resistant properties can be used to good effect: in sea defences, roadworks,' and as baulks for shoring up trenches, rivers, and ditches. ■ Yet still, all over the country, this enormous reserve of usuable timber is being left to rot. Even when elms are being cleared, contractors are being paid to take them away when the value of the timber could in some

instances exceed the cost of felling. A do-it-yourself mobile sawmill, the Forester Bandmill, made by a Wandsworth engineering firm, is ideal for the job. It can saw logs of up. to 6ft diameter and of unlimited length; and, at $20,000, is .a thoroughly

economic proposition for a local authority. For wildlife, the loss of so many elms is not quite the disaster many people might have imagined. “Of course it is catastrophic,” says. the. Nature Conservancy Council’s chief advisory officer (Dr Norman Moore,) “but it is

basically a landscape problem.” The one major wildlife casualty is likely to be the white-letter hairstreak, a butterfly whose caterpillars feed on nothing but elm leaves. Already uncommon, it could become one of Britain’s rarest species in the next few years. Meanwhile the search for a cure continues. Healthy trees can be injected with fungicide, but the treatment has to be repeated every year and is too expensive to be widely-employed. Jack Atanackovic. a Portsmouth plant pathologist, has evolved a method of rendering elms beetle-proof by coating the trunks with a cocktail of engine oil and insecticide. And. in desperation, Basildon New Town even tried importing from Austria a

rare variety of wasp, whose larvae destory the elm beetle grubs. All to no avail. Nothing, it seems, can stop the disease in its tracks. Now it is spreading north, putting a further seven million elms in jeopardy. Already outbreaks have been reported as far north as Perthshire. The tragedy could not have come at a worse time. Dutch elm disease has struck during a period in which old landscape patterns are being dismantled by bulldozers. Many hedgerows are no longer functional; the timber they sypported is obsolete. The sad truth is that, long before Dutch elm disease, broad-leaved trees had become an irrelevant luxury. Farmers don’t want them. Local authorities can’t afford them. Too many of our trees are

middle-aged or have become stag-headed geratic relics waiting for the next gale to send them crashing. When they fall they are not replaced. Local authorities last year planted a mere 50.000 young trees, and many of these will have perished in the dro ight. There remains one slim hope. Elms regenerate by sending out suckers. If some of these can survive until the plague has run its course they may yet reach maturity in tomorrow's hedgerows. Between now and then the outlook is bleak indeed. “We shall soon be entering a period in which the English countryside will be virtually denuded of free-standing trees," warns Reg Hookway, director of the Countryside Commission. It is an appalling prospect.

“. . . \ single giant, elm can become a crawling tenement for 200.000 beetles."

Has the time come to write the obituary of the elm tree? For centuries this underrated tree, along roadside and hedgerow, has sustained the illusion of England as a woodland country. Now the great elms are disappearing fast. Dutch elm disease is laying waste the countryside of England and the Continent, as well as North America, leaving millions of dead and dying trees in its wake. Conservationists see a "ghastly vision of winter-in-summer” that will remain to haunt English people for years to come. BRIAN JACKMAN reports in the London “Sunday Times”:

. Nothing, it seems, can stop the disease in its tracks.”