Anyone visiting woodland around the Kiltarlity and surrounding areas to the north of Loch Ness, is being asked not to take any tree foliage, branches, or twigs away with them, in a bid to help guard against a potential threat to Scotland’s pine forests.
The call comes as Forestry Commission Scotland continues to work with landowners, foresters and conservationists to take a sensible, risk-based approach to the management of a localised population of the Pine tree lappet moth, the caterpillars of which have sometimes been known to cause large-scale damage to pine plantations in some parts of continental Europe.
First found in Scotland in this area in 2004, a breeding population was confirmed in 2009. Strict control measures preventing the movement of bark-covered timber were then put in place.
Hugh Clayden, the Commission’s tree health policy adviser, said: “The potential threat comes from the caterpillars of this large moth, which feed mainly on pine needles and can completely strip trees of their foliage if outbreak conditions arise.
“Taking any foliage or woody material away from affected forests could potentially help these moths to move to other areas so we are asking members of the public to assist us by leaving such material in the forest as it could harbour either eggs or caterpillars of the Pine tree lappet moth.”
Eggs are laid on needles, twigs or bark around late May to mid-August and the caterpillars then feed until the first frosts arrive. They travel down the trunk to over-winter underground and in the early spring emerge to travel back up the trunk to once again feed. The caterpillars can grow to be 5-8cm long before they pupate.
Hugh added: “Our initial timber movement controls bought us the time needed to investigate the life cycle, potential origins and likely impacts of this impressive moth. Based on that expert advice we now feel able to reduce the level of timber movement controls so that woodland owners can resume active management of their forests – which, in the longer term, is by far the best way to keep them healthy and resilient to the wide variety of insect pests and tree diseases found in the natural environment.
“But that’s not to say that we are giving the ‘all clear’ or being complacent about the potential threat from the Pine tree lappet moth. We will still be monitoring the area and working through an Outbreak Management Team to ensure our response remains balanced and risk-based. And everyone using these woodlands can help us by taking the above, simple measures to prevent this moth from spreading outside the area.”