Here is the latest press release from th Forestry Commission concerning the spread of Chalara. There’s a link to a useful map toward the bottom of the piece and a video which gives good examples of how to identify the disease from both the leaf and the stem.
Survey reveals ash disease in six more counties
Issued jointly with Defra
Further cases of the tree disease Chalara dieback of ash have been
confirmed in woodland in Sussex, Berkshire, Bedfordshire, Lincolnshire,
Yorkshire and Northumberland after an unprecedented survey of Britain’s
established woodlands.
The disease has now been confirmed in 115 sites: 15 nurseries, 39
planting sites and 61 locations in the wider environment (forests and
woodland).
These instances of Chalara dieback are being discovered as a result of a
rapid and intensive surveying operation carried out over the course of
last weekend and the beginning of this week.
The discovery of the disease in these counties does not mean the disease
is spreading rapidly. 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.
Plant health experts, in conjunction with volunteers from groups such as
the National Trust and Woodland Trust, have been examining about 2500
blocks of land, each 10 kilometres square, where mature ash trees are
known to be present in order to seek out traces of the disease in
established trees.
At the same time, plant health experts have been undertaking an urgent
check of 220 prioritised sites which have received saplings from
nurseries where Chalara was found to be present. Taken together, these
surveys will give a much better picture of the extent of Chalara
throughout the country, but will not have identified all cases of the
disease; it is likely that more cases will emerge as checks continue.
Martin Ward, Chief Plant Health Officer, said:
“We have thrown all possible resources at this surveying exercise, which
has given us a much clearer picture of the distribution of the disease
to inform our evidence base.
“The science on Chalara is still emerging, and the more evidence we
have, the greater our knowledge and understanding of this disease and
the better we are able to tackle it.
“I’d like to thank everyone involved in this survey. Together we’ve
surveyed more than 92 per cent of England and all of Scotland and Wales
so far – a tremendous achievement, especially in such a short time,
which shows our combined determination to deal with Chalara.”
Common ash (Fraxinus excelsior) is a species of broadleaf tree native to
Great Britain, providing about five per cent of all woodland cover.
Chalara dieback is a serious disease that has affected a high proportion
of ash trees in northern Europe, and it was first confirmed as present
in the UK in nursery stock in March.
A map showing all locations with confirmed cases of Chalara, and further
information, is available at www.forestry.gov.uk/chalara.
Latest update 9th Nov
The effort to address the ash tree disease Chalara dieback will mobilise
the general public and focus attention on trees which show resistance to
the disease as part of an action plan announced today by Owen Paterson,
Environment Secretary in the UK Government.
Following an unprecedented effort across Great Britain to identify areas
where Chalara dieback has infected trees in the wider environment, the
Government this week brought together scientists, campaigners,
charitable groups and woodland agencies to discuss what action should be
taken.
The immediate plan of action was agreed at the Government’s emergency
committee COBR, which Mr Paterson chaired this morning.
After the meeting, the Environment Secretary set out the Government’s
objectives for tackling Chalara. These are to:
* reduce the rate of spread of the disease;
* develop resistance to the disease in the native UK ash tree
population;
* encourage citizen, landowner and industry engagement and action in
tackling the problem; and
* build resilience in the UK woodland and associated industries.
Mr Paterson set out an immediate plan of action to meet those
objectives, building on the ideas discussed at the Chalara and Tree
Health Summit on Wednesday, 7 November. The advice of stakeholders,
scientists and other experts at that discussion, agreed today at the
COBR meeting, was that in the short term:
* newly-planted diseased trees and diseased trees in nurseries will be
traced and destroyed, because once young trees are infected they succumb
quickly;
* mature trees will not currently be removed, because they are valuable
to wildlife, take longer to die, and can help us learn more about
genetic strains which might be resistant to the disease. Infection does
not occur directly from tree to tree;
* better understanding of the disease will be built through research and
surveys, which will look not only for diseased trees, but also for those
which show signs of genetic resistance to Chalara fraxinea infection, to
help identify genetic strains resistant to the disease;
* the search for the disease will include trees in towns and cities as
well as the countryside, building partnerships with a range of
organisations beyond Government;
* foresters, land managers, environmental groups and the public will be
informed about how to identify diseased trees and those likely to be
resistant to the disease, and know what to do if they find a diseased
tree.
The Government has already introduced a number of control measures to
reduce the speed of spread, which are in line with these
recommendations. A ban on imports of ash trees and movement of ash trees
and plants around the country remains in place. Immediate action is
being taken to remove and destroy infected trees found in nurseries or
in recently planted sites.
Where infection is found in mature trees, the scientific advice is to
leave them where they are, because infection does not spread directly
between trees, but only via the leaf litter.
Speaking after the COBR meeting, Owen Paterson said:
“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.
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.
“The groups that put such a lot of effort into looking after our
wildlife and our countryside will play a major role in minimising the
impact of Chalara, and so will the general public, especially when it
comes to spotting other areas where the disease has taken hold.
“Our plans have been developed through bringing together Britain’s top
experts and listening seriously to their advice. We now have a window of
opportunity for action because the disease only spreads in the summer.”
Over the coming weeks the Government will work with scientific experts
and other interested groups to further develop and implement the
measures in the plan, and to set a longer-term approach to tackling
Chalara. COBR agreed that this approach will also consider:
* designating protected zones, to free up trade in ash from areas free
of the disease through authorising businesses to issue “plant
passports”;
* establishing a tree health early warning network to provide advice,
screening and initial diagnostics;
* developing advice on protecting saplings and responding rapidly if the
disease is found;
* developing advice on sustainable management of mature trees on sites
affected by Chalara;
* what additional equipment is needed to diagnose tree disease;
* improved biosecurity including import controls; and
* more public engagement in helping to diagnose and tackle disease
through “citizen science”, including an OPAL (Open Air Laboratories)
citizen science project.
Details of the plan of action are available at
www.defra.gov.uk/news/2012/11/
Information about Chalara, including videos about how to identify the
disease, and details of confirmed cases in new plantings and the wider
environment, can be found at www.forestry.gov.uk/chalara.