Tree felling in the Coniston area

View of Tarn Hows

A number of trees have been found to be infected with a fungal-like disease in woodland in the Coniston area, but our rangers, forestry team and the Forestry Commission are working hard to quickly remove these infected trees to prevent the virus from spreading.

Why are there red lines on some of the trees in the woodland around Tarn Hows?

We’ve found trees in the woodland at Tarn Hows which are infected with the disease Phytopthora ramorum. In order to control the spread of this disease a buffer zone of at least 100m has to be felled around each infected tree. This is a legal requirement. The red marks on the trees are measurements from the infected tree so that foresters know where to work.

What is Phytophthora ramorum (Pr.)?

Phytopthora ramorum is a fungus-like virus which causes extensive damage and death in a wide range of trees and shrubs.

The disease is known in the USA as 'sudden oak death', but luckily it has little effect on British oak trees. However, larch trees – which are widely grown in the UK for the timber market – are particularly susceptible and large numbers have been affected.  It spreads quickly and easily via spores. Approximately 14% of the Trust's woodland in the south Lakes is larch.

How did the trees catch the disease?

The first confirmed case of Phytopthora in the UK was in 2002. Since then, it’s likely that in many cases the disease has spread to larch trees from Rhododendron ponticum, a common invasive, non-native species present in many British woodlands. Rhododendron is highly susceptible to the disease, and once infected it produces large numbers of spores. The evidence indicates that these spores can be spread over several miles in mists, air currents, watercourses and rainsplash, so, once infected, tall larch trees growing on a wet Cumbrian fellside are an almost perfect way to spread the disease. 

It can also be spread by footwear, dogs' paws, tools, equipment, bicycle and other vehicle wheels. Movement of infected plants is also a key means of spreading it over long distances.  Please clean your boots, bike/pram wheels and paws when you leave Tarn Hows.
Movement over short distances by wild animals such as deer and wild boar might also be possible, although there is little to indicate that small mammals like squirrels transfer the disease from tree to tree.

Are these spores dangerous to humans, dogs or other wildlife?

No.

Isn’t there a way to treat the disease?

There is no cure for Phytopthora ramorum and there are no effective chemical treatments available. There are fungicides which can suppress the symptoms, but none which can kill the virus.

Is it confined to the woodland around the tarn or has it reached other parts of Coniston?

The Trust had three sites infected with Phytopthora at Claife on the shores of Windermere a few years ago. There are other confirmed sites at Guards Wood and Tarn Hows Wood and on the shore of Tarn Hows itself.  Other private landowners across the Lakes including the Forestry Commission have also been affected. The Trust’s forestry team has already started work on two sites near Coniston.  We are working with the Forestry Commission to plan how we tackle the larger site in Big Wood south of Tarn Hows. 

How long will the felling take?

Infected trees release huge numbers of spores in September so we hope to have most of the larch trees felled by then.

Will the paths still be open?

We will try to keep paths open but it will be necessary to close some temporarily during the work for safety reasons. Please pay attention to any diversion signs which may be put up on site. It’s really important to keep to these paths to prevent the spread of infected material to other sites.

What happens to all the wood?

The timber can still be used but to minimise the risk of spreading the disease any movement of diseased wood from a forest or woodland to a mill or processing site requires a Forestry Commission movement licence.

Will you plant new trees?

We will establish trees on the affected sites either by allowing natural regeneration or by replanting. We will allow glades and denser areas of woodland to develop over the next few decades. We may decide to replant some areas with conifer species.  Mixed woodland can provide a great wildlife habitat while still producing a supply of sustainable timber.

Can anything be done to prevent this from happening again?

Certain types of weather will enable the spores to spread more easily than others – so the warm wet autumn last year is in some parts responsible for the outbreak. By working together with the Forestry Commission and neighbouring woodland owners and getting the infected trees felled as soon as possible we hope to prevent the spread of the disease in years to come.

How can I help?

All visitors to the countryside can help by paying attention to signage on site, staying on marked paths and cleaning mud and needles off their boots, bike or pram wheels and dog paws.

If you have further questions please get in touch with our Assistant Woodland Ranger Leila Todhunter (leila.todhunter@nationaltrust.org.uk)