Ash dieback: the ruined Polish forest where deadly fungus began But ash dieback has now been confirmed in the wild from Sussex in the South to Renfrewshire in Scotland. "We're now at a stage where we are beyond containment and eradication," says Dr Glynn Percival, a plant physiologist at the University of Reading who is advising the British Government. We're now looking at management. That may not be possible, judging by what has happened in other countries. Lithuania has lost all its trees to the disease, for example, and Denmark has lost nine out of 10. I have an appointment to meet the Polish scientist who identified and named the fungus responsible, Chalara fraxinea, and who is now the world's leading authority on the subject. But first I have come to the remote Zabodny forest, three hours north of Krakow, to see what it does. When Artur Ratusznik and his colleagues noticed the leaves of young ash trees turning brown at the wrong time of year, in the early Nineties, none of them knew why. "The ash is very sensitive to frost, so we thought the damage was being done by the last frost of the year, the one that comes in spring," says Mr Ratusznik. We were not paying attention to the possibility of disease at first. His team has 44 officers to cover an area of 14,700 hectares, with hundreds of thousands of trees to inspect. The only dense gathering of ash trees was in an obscure corner of the estate, covering 150 hectares. The mix happened to match what you might find in an English forest, which makes the story all the more alarming. The mystery fungus killed the leaves first, then moved into the stalk and down the trunk, cutting off the water supply and choking the tree. Then it rotted the roots. "We asked scientists to come and help us, but they couldn't work out what was going on," says Mr Ratusznik. We have since been told the disease was always here, it just wasn't activated. That is one theory. The disease could have been born in this place, when an existing fungus mutated among the trees. It could also have come from Asia, carried on the wind, or on the leaves of an imported plant, or the clothes of an unwitting tourist. The latter explanation seems unlikely, because to get to the forest you have to drive out of the village of Zabodny, turn onto a rough track, then an even rougher one that becomes a swamp as it follows the course of the Black River. And the young trees that died here were grown from local seeds. "There were no imports," says Mr Ratusznik, who thinks the current row in Britain is largely irrelevant. The British government has been criticised for not banning the import of ash trees from the Continent as soon as it became obvious there was a problem overseas. Five million were imported to Britain between 2003 and this year. The Department for the Environment, Food and Rural Affairs says: "It is likely that the disease has been present in these areas for a number of years, originally caused by spores blown in from mainland Europe." Mary Creagh, the shadow environment secretary, calls that "desperate spin" to hide the reality that more could and should have been done sooner. But events in the Zabodny forest suggest it would all have been in vain. By 2003, the fungus had moved into the older trees, some of which had been planted in the time of Stalin. Still the full horror of what was happening here was not revealed until one night in February 2007, when strong winds blew. "It was like a hurricane," says Jaroslav Chatys, 39, a specialist forester. Very strong. That night we lost 3,000 trees. That was the first time we realised the scale of what was happening. The devastation that followed over the next few years was total, he says. There is nothing left. For the purposes of research, one patch of woodland has been left exactly as it was, and dead ash trees lie there in each other's embrace. As we inspect them, the light is fading. Bitterly cold wind brings hail and makes the tree bones creak. One makes a sound like a squeal. "I think we want to leave," says Mr Chatys, fearful of falling limbs. That's the reason why the people of Sussex used to call the ash tree "the widow maker." The Latin name of the variety of the tree most commonly found in Europe is Fraxinus excelsior, but its common name, ash, comes from the Old English word for spear, the shape of the leaves. We retreat to the 4x4 marked "Sluzba Lesna," the name of Poland's forestry service, and then to the office of Mr Ratusznik, 49, who has been a forester for 25 years. His room is dominated by a large Polish eagle symbol on one wall and the even larger mounted antlers of a stag on the other. "This deer was hit by a train," he says. The walls are clad in a gorgeous, honey-coloured wood that turns out to be ash. He has noticed that the trees that survived appear to be immune, so they are being used to seed new ones in the hope that their immunity can be passed on. The question remains, how does he think the disease got here? Mr Ratusznik throws his hands open, sips his coffee and finally shrugs. Ask Dr Kowalski. Back in Krakow, in an office block at the University of Agriculture, Prof Tadeusz Kowalski is waiting. "We realised it could not be the frost, because the leaves were turning brown in September," says the 62-year-old. The spores that cause this come to life during the summer vacations. Intensely passionate about his subject, he spreads samples out on his desk, Petri dishes and test tubes stoppered with cotton wool, next to tea cups and Jaffa cakes. After years of research, in 2006 he identified the cause of the disease as a new fungus, Chalara fraxinea. But species of fungus often have two forms, and he had only found one. "Then I found this in the forest," he says, unwrapping a roll of green blotting paper to reveal brown ash twigs dotted with little toadstools. These created the spores that spread the fungus. This was the missing second form of Chalara fraxinea, although confusingly, he called it Hymenoscyphus pseudoalbidus. Prof Kowalski does not rule out the possibility that it was created by natural genetic mutation in the forests of Poland. However, a second theory is gaining more support in the scientific community. "There are suggestions that Hymenoscyphus pseudoalbidus comes from Asia, where it lived on a different species of ash tree and caused no damage," he says. Then it came here, perhaps carried by the wind or by birds, or on clothes, and found the European ash more vulnerable. Until the latest research is confirmed, he is not willing to say for sure. He does, though, think the row over imports in Britain is irrelevant now, or at least too late. His own research does suggest one possible clue for British scientists. Cooler temperatures in summer are better for some strains of the disease, so it is possible that the colder, wetter summer in Britain this year could have contributed to what is happening there. Prof Kowalski does have some hope for the future. In most instances in Poland, we are finding that 15 to 20 per cent of trees do not die, and show no symptoms. They are survivors. It may be possible to develop resistant varieties of ash in the future, and find a solution to this problem. But in the meantime, millions of British ash trees may be doomed. Acres of our forests may soon look like the devastated clearing in Zabodny. Back there, Mr Ratusznik questions me closely about the extent of the disease in Britain. How many trees are at risk? Eighty million. He looks shocked. Has it been seen in the older trees? It has. This experienced man of the forests puts his hand on his heart. Then I am afraid it is over for you. It is too late. The game is over.