Northern Ireland is close to the point where it will be impossible to eradicate a virulent disease from the forests where it has taken hold, according to Forestry Minister Michelle O'Neill.
The Phytophthorum ramorum pathogen has now swept into the west of the province, with new cases of the disease confirmed in counties Fermanagh, Antrim, Down and Armagh.
Forest Service machinery is now fully stretched and the Government is having to turn to the private sector to help contain the disease, which has swept through commercial Japanese larch plantations across Northern Ireland, Forest Service chief executive Malcolm Beattie has revealed.
By spring this year 600 hectares had been felled.
Last night he revealed that another 360 hectares of forestry will have to be felled this winter.
He stressed that priority will be given to protecting vulnerable sites from infection, such as the tree collections at the National Trust's Castle Ward property and the arboretum at Castlewellan.
Tree felling is already being carried out on larch plantations surrounding the vulnerable Breen Oakwood, one of the few remaining pockets of native ancient woodland in the Glens of Antrim.
The disease has also swept through Glenariff Forest Park in the Glens and forestry officials are discussing whether to replace the decimated woodlands with another less vulnerable species of conifer or a broadleaf species.
There are fears that the disease could spread to native species.
Minister O'Neill said: "We will continue to fell trees where it is sensible to slow down the spread of this disease and to protect important plant collections and conservation sites. Unfortunately, once the disease is well established in the woodland environment it is impossible to eradicate, and as is the case in south west Scotland, we are close to that point in the north of Ireland.
"Therefore, I have decided to re-evaluate our policy options so that we can prioritise the use of our resources in the most effective way across all plant diseases.
"Our forests very much remain open and visitors are extremely welcome but I would ask members of the public to be aware of and observe bio-security guidance. Visitors can reduce the risk of spread of the disease by taking simple steps to remove mud from their boots and shoes, clothing or bicycle tyres before and after their visit," Ms O'Neill added.
Phytophthora ramorum originated can kill many tree species but appears to attack Japanese larch first. The first indication is a wilting of shoots. Later are withered shoot tips with yellowing needles, which become blackened. Trees may also have bleeding cankers.