Ash trees make up around 5% of woodland in Britain, according to Forestry Commission Photograph: Maxim Toporskiy/Alamy
Scientist in charge of tackling the spread of the deadly ash diebackfungus that has devastated woodlands in parts of Europe has conceded the fungus could be disastrous for Britain's ash trees with serious knock-on ecological consequences.
Professor Ian Boyd has been put in charge of a government task force dealing with the crisis as a ban on the import and movement of ash trees comes into effect on Monday.
Boyd, chief scientific adviser at the Department for Environment, Food and Rural Affairs, said there was a small chance that Britain's ash trees may have a resistance to the disease.
But speaking to the BBC Radio's World This Weekend he added: "We don't know that yet. In general we have to accept that this is a bit of a disaster for our ash trees."
He said his team was considering the kind of emergency measures used to tackle the spread of animal diseases like foot and mouth or bird flu.
"With plants we don't have as instant a reaction ... as we do with animal pathogens. And maybe we ought to be moving in that direction," he said. More than 100,000 ash trees have been destroyed so far in England and Scotland.
Boyd added: "Ecologically it is going to change the countryside very significantly. Parallels have been made with Dutch elm disease of the 1970s. This is not good news for the countryside."
Around 100 staff have been redeployed from the Forestry Commission and the Food and Environment and Research Agency are to focus on the crisis after 10 cases of the disease were confirmed in separate woodlands in East Anglia. With a further 12 sites in East Anglia and Kent awaiting results to confirm the disease.
Last year trade unions at the Forestry Commission warned the Commons' science and technology committee that a 25% budget cut would hit the agency's ability to detect the spread of tree diseases.
A leaked staff consultation document from February last year said: "There is no capacity to deal with costs of disease or other calamity."
The government has denied opposition claims that it has been slow to react to discovery of the disease in Britain.
The fungus, known as Chalara fraxinea was first discovered among trees imported to a nursery in Buckinghamshire in February.
It causes leaf loss and can lead to the death of the tree. It has wiped out between 60% to 90% of ash trees in some areas of Denmark and is becoming widespread throughout central Europe.
The latest cases in East Anglia and Kent are thought to have spread by the wind from the continent. The location of infected sites offers some hope that the disease can be contained, according to Forestry Commission spokesman Charlton Clark.
"We don't want to be complacent, but if it is confined to a relatively small number and area in East Anglia then we might decide that it is worth the effort and expense of trying to eradicate it," he said. "If too many sites and trees are involved then the policy probably would be containment to stop it spreading out of East Anglia, There's a hope that at worst we can contain it in that area. If the wind is able to throw it further across Britain, then we would be looking at a very difficult situation."
Clark said it was too early to estimate the cost of trying to eradicate the disease.
One cause for hope is that the disease has not been found in woodland outside East Anglia and Kent, Clark said. "We have been getting very few reports from elsewhere in the country. In fact the reports we have been getting from elsewhere show that ash is looking quite healthy this year. That's hopeful sign that maybe it hasn't spread that far," he said.
Clark pointed out that ash trees make up around 5% of woodland in Britain, not a third of British trees as some newspapers have reported.
University of East Anglia researcher Chris Panter said that if ash trees suffer large scale declines, 60 of the country's rarest insect species could be at risk of being lost from Britain.
"As well as 80 common insects, at least 60 of the rarest insect species in the UK have an association with ash trees – these are mostly rare beetles and flies," he said.
Scarce species could become even scarcer and may even be lost, he warned.
"Ironically, many of the rare species associated with ash depend on the dead or dying branches of old trees, but if infected trees are ultimately cleared away then even these species will suffer also.
"Ash is also important for many lichens and mosses that grow in its bark, and its seeds are an important food for wood mice," he added.
Rene Olivieri, chairman of The Wildlife Trusts, said: "Ash trees, as hedgerow and field trees, are an important feature in our landscape and also a key component of ecologically unique woodlands that support rare species.
"For example, upland ash woods, such as those in the Peak District, support rare woodland flowers, a rich invertebrate fauna and important lichens.
"Their loss would have a dramatic negative impact on our natural environment."
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