Slievenacloy ASSI

Slievenacloy is an area of marginal agricultural grassland in the Belfast Hills. Soils have developed from glacial tills and are generally surface-leached. However, because of poor drainage in places base-enrichment by springs and surface flushing occurs. This has led to the development of a wide range of grassland types, reflecting the varied soil conditions.

Over much of the area, the vegetation is dominated by sharp-flowered rush and Yorkshire fog, but with a wide variety of associated species, including herbs such as Devil's-bit scabious, cuckooflower, tormentil, marsh willowherband meadow buttercup. More pronounced flushing produces localised stands of very species-rich vegetation, with a predominance of sedges such as glaucous sedge, carnation sedge, tawny sedge and, more notably, Dioecious sedge.

Drier areas are characterised by a range of different grassland species in which common bent is prominent; however, these grasslands are generally very species-rich and include a wide range of herbs, such as white clover, cat's ear, self-heal, eyebright and meadow vetchling, in addition to a number of other grasses and sedges, eg. sweet vernal grass, red fescue, Yorkshire fog and carnation sedge.

More elevated ground illustrates transitions to wet heath vegetation, in which acid-tolerant species such as heather, purple moor-grass and Sphagnum bog mosses are dominant.

The Belfast Hills in general contain a concentration of unimproved grassland, a resource which is not of widespread occurrence in Northern Ireland, nor indeed in the British Isles. Slievenacloy is particularly notable for the diversity of its grassland communities and the large area which this species-rich vegetation occupies.

At least seven species of orchid have been recorded from the site and there is a breeding colony of the marsh fritillary butterfly whose larval foodplant, the Devil's-bit scabious, is widely distributed over the area.