The status ofCalluna vulgaris(L.) Hull on Fair Isle

Abstract

Summary A survey and sampling programme was carried out in May and September 1992 to assess the health and status of Calluna on Fair Isle. A floristic survey and a range of investigations of Calluna plants and shoots, based on a 200m grid, were undertaken on the common grazing area in the northern part of the island. The investigation showed that Calluna-dominated vegetation extends over 53% of this area. A further 25% is accounted for by mosaics of Calluna heath and grassland communities, and 15% by a coastal fringe of maritime grassland. In general the Calluna was observed to be in poor condition with checked growth, low production and appreciable dieback. Mean height of Calluna over much of the area was less than 4 cm. Estimates of utilization indicate that sheep grazing is leading to a loss of cover of Calluna only in localized areas of heath-grassland vegetation. It is suggested that the present condition of the Calluna heath is principally due to the effects of severe climate, exacerbated by the ext...