A fungus-like organism, Phytophthora ramorum, has spread through the release of infective spores, affecting about 6,500 trees.Staff in Forest Service and the NI Environment Agency (NIEA) are taking the action in order to reduce the risk of the disease spreading to other species at the forest, which contains some of the oldest trees in Ireland.A spokesperson for the Forest Service said: "Action to fell approximately 6,500 larch trees is underway as this is the most effective way of reducing the risk of the disease spreading to other trees and gardens in the Belfast area."Consultation has been carried out with key stakeholders as part of the planning process in advance of the felling operation.''The disease presents no risk to humans or animals, although the temporary loss of habitat for wild animals is inevitable.Forest ServiceThe Forest Service also appealed to the public to help in the control of the disease.''Although felling work is planned to start immediately, Belvoir forest remains open to visitors. However, visitors to the forest should follow the guidance detailed on signs at the affected sites," the spokesperson continued.''It is especially important to avoid any action which could result in the movement of infected soil or plant parts to uninfected areas."Visitors are also urged to ensure their bicycles and footwear are free of any soil before visiting other areas."A spokesperson for NIEA said: ''These trees contain a wealth of biodiversity interest providing a historical and cultural link to our past."Some of these trees were present when Belfast was little more than a village. Many of these veteran trees are growing within the larch plantations that need to be felled."In many ways, this felling should ultimately benefit the veteran trees and we have worked closely with Forest Service to ensure that the felling of disease affected trees is carried out as sympathetically as possible to minimise the potential threat to the veterans.''