Nov 2012. New field layer management trials to test the potential application of brush-cutting as a means of improving habitat conditions for Twinflower are being set up in the Park.
Recent surveys have revealed that, at some sites, the vegetative growth and flowering of Twinflower is limited by tall and dense sub-shrubs in the surrounding field layer. This problem is particularly apparent in situations where the woodland canopy is open and grazing levels are low, and the field layer becomes dominated by a rank growth of Heather (Calluna vulgaris). In extreme cases, there is a risk that Twinflower may be shaded out altogether by dense overtopping vegetation.
In order to address this problem, new trials are being established by the Cairngorms Rare Plants Project in collaboration with landowners in the Park, including Glen Tanar Estate and Mar Lodge Estate, to investigate the impact of Heather cutting on the growth and spread of Twinflower. Experimental plots are being set up at Twinflower sites where previous surveys have identifed that dense vegetation in the field layer is a key limiting factor. At these sites, brush-cutting treatments are being applied to half of the Twinflower patch area, and a zone beyond it, leaving half of the area as an untreated control. Plots will be monitored every two years for a total of 6 years to measure any changes in the growth and spread of Twinflower in response to this treatment.