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Owen Paterson: Ash dieback will not be eradicated | |
(about 1 hour later) | |
By Mark Kinver and Matt McGrath BBC News | |
Environment Secretary Owen Paterson has acknowledged that ash dieback, a disease that threatens the UK's ash trees, will not be eradicated. | |
Announcing the government's action plan to tackle the disease, Mr Paterson said efforts would focus on slowing its spread through the countryside. | |
Diseased young trees would be removed and destroyed, he added. | |
But the action plan does not aim to remove mature trees, which are important for wildlife. | |
It adds that efforts will also focus on developing resistance to the disease. | |
"The scientific advice is that it won't be possible to eradicate this disease now that we have discovered it in mature trees in Great Britain," Mr Paterson said. | |
"However, that does not necessarily mean the end of the British ash. | |
"If we can slow its spread and minimise its impact, we will gain time to find those trees with genetic resistance to the disease and to restructure our woodlands to make them more resilient." | |
Survey results on Wednesday confirmed that the disease was present at 115 sites in England, Wales and Scotland. | Survey results on Wednesday confirmed that the disease was present at 115 sites in England, Wales and Scotland. |
The action plan outlined a number of areas where government efforts would be focused. These included: | |
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It explained that newly-planted diseased trees and diseased trees in nurseries would be traced and destroyed because once young trees become infected, they succumb to the pathogen. | |
Known as the common or European ash, the tree - the UK's only native ash species - is scientifically known as Fraxinus excelsior. | Known as the common or European ash, the tree - the UK's only native ash species - is scientifically known as Fraxinus excelsior. |
It is the UK's third most abundant species of broadleaved tree (after oak and birch), covering 129,000 hectares of woodland. | It is the UK's third most abundant species of broadleaved tree (after oak and birch), covering 129,000 hectares of woodland. |
Ash is deemed to be a very important species within the UK's hedgerows and accounts for about for about 10% of the nation's estimated 123 million "non-woodland" trees. | Ash is deemed to be a very important species within the UK's hedgerows and accounts for about for about 10% of the nation's estimated 123 million "non-woodland" trees. |
The common ash is a large deciduous tree that can reach heights in excess of 40 metres (130ft). It can live up to 400 years but coppiced trees can live for centuries longer. The species is wind-pollinated, and the seeds (known as keys) are primarily dispersed by the wind. | The common ash is a large deciduous tree that can reach heights in excess of 40 metres (130ft). It can live up to 400 years but coppiced trees can live for centuries longer. The species is wind-pollinated, and the seeds (known as keys) are primarily dispersed by the wind. |
As the species is long-lived, it is important for wildlife. It supports specialist deadwood species such as the lesser stag beetle and hole-nesting birds including owls and woodpeckers. | As the species is long-lived, it is important for wildlife. It supports specialist deadwood species such as the lesser stag beetle and hole-nesting birds including owls and woodpeckers. |
Ash woodlands have light, open canopies, so are an important habitat for flora such as bluebells and ramsons. Birds such as bullfinches feed on the trees' seeds. | Ash woodlands have light, open canopies, so are an important habitat for flora such as bluebells and ramsons. Birds such as bullfinches feed on the trees' seeds. |
Also, ash provides an important habitat for more than a quarter of Britain's lichen, including nearly 14% of the nationally rare/scarce species. | Also, ash provides an important habitat for more than a quarter of Britain's lichen, including nearly 14% of the nationally rare/scarce species. |
Upland mixed ash woodlands are listed as a priority habitat under the UK Biodiversity Action Plan. | Upland mixed ash woodlands are listed as a priority habitat under the UK Biodiversity Action Plan. |
href="/news/science-environment-20253767" >Minister: Ash killer here to stay | |
However, there was no intention to fell mature trees because as well as being important to wildlife, they take longer to die and could provide vital clues for scientists looking for genetic strains that might be resistant to the disease. | |
The latest data showed that infection did not occur directly from tree to tree, only via leaf litter. | |
A ban on ash imports and the movement of trees from areas with confirmed cases of dieback came into force on 29 October, just days after government scientists confirmed that the disease had reached the UK's natural environment - at sites in East Anglia. | |
Dieback, caused by the Chalara fraxinea fungus, was first recorded in eastern Europe in 1992 and spread over two decades to infect most of the continent. | Dieback, caused by the Chalara fraxinea fungus, was first recorded in eastern Europe in 1992 and spread over two decades to infect most of the continent. |
The first confirmed cases in UK woodlands were at sites in Norfolk and Suffolk. Scientists said the infections were most likely to have been the result of spores from the fungus being blown across from mainland Europe. | The first confirmed cases in UK woodlands were at sites in Norfolk and Suffolk. Scientists said the infections were most likely to have been the result of spores from the fungus being blown across from mainland Europe. |
But questions are being asked whether this is the case for infections recorded in places such as South Wales, Yorkshire and Northumberland. | But questions are being asked whether this is the case for infections recorded in places such as South Wales, Yorkshire and Northumberland. |
"This isn't just about wind - science tells us human movement of plants and plant material is a key way this fungus has spread across Europe," said RSPB forestry officer Nick Phillips. | |
"And this isn't just about Chalara - there's a long list of other tree diseases and non-native species that are already on our shores. | "And this isn't just about Chalara - there's a long list of other tree diseases and non-native species that are already on our shores. |
"We're a European island nation with strong international trading links. What we need now is a carefully considered response to minimise any further collateral damage to our trees and wildlife." | "We're a European island nation with strong international trading links. What we need now is a carefully considered response to minimise any further collateral damage to our trees and wildlife." |
The most visible sign that a tree is infected with Chalara ash dieback is bleeding sores and cankers on the bark, and discolouration of the underlying sapwood. | The most visible sign that a tree is infected with Chalara ash dieback is bleeding sores and cankers on the bark, and discolouration of the underlying sapwood. |
The sores often surround branches in the infected area of the tree, causing the dieback of shoots, twigs, branches and smaller stems. | The sores often surround branches in the infected area of the tree, causing the dieback of shoots, twigs, branches and smaller stems. |
The disease has also been shown to infect ash tree leaves, appearing as blemishes. | The disease has also been shown to infect ash tree leaves, appearing as blemishes. |
There are numerous other diseases that display similar symptoms, making it difficult to identify for most people. | There are numerous other diseases that display similar symptoms, making it difficult to identify for most people. |
The Forestry Commission has issued guidance on how to identify the disease. | The Forestry Commission has issued guidance on how to identify the disease. |