Scottish Natural Heritage has started a 3 year project to control Himalayan balsam in the catchment of the Lunan Burn, a tributary of the River Tay in Perthshire. The plant is attractive but highly invasive along river banks, loch shores and in wetlands. It can swamp native vegetation but then when it dies back in winter it leaves bare soil which is susceptible to erosion during flooding.
It has been found in small quantities along the Lunan Burn upstream of Lochs Marlee and Clunie, both part of internationally important wildlife sites. A local landowner expressed concern that it will spread rapidly and soon become uncontrollable. SNH agree and hope that a quick response could stop it reaching that stage. Lochs Clunie and Marlee and other lochs in the Lunan Burn catchment have been the subject of an SNH management scheme to reduce nutrient run off to improve water quality. Large scale soil erosion would be a major setback to that work.
This year SNH plans to work with local landowners to target and kill Himalayan balsam where it is known to grow and then survey the remainder of the catchment. Follow up work will take place in 2013 and 2014.