Ballymacallion ASSI

This area is of special scientific interest because of its species-rich grassland.

Species-rich grassland tends to occur only where land management is not intensive, in particular where traditional farming practices have been maintained. As a result, it is not a widespread habitat in Northern Ireland and is often fragmented, consisting of individual fields, parts of fields or banks. Species-rich dry grasslands, like some of those found at Ballymacallion, are a particularly scarce resource in Northern Ireland, even in this area, where there is known to be a greater proportion of this habitat type.

Ballymacallion is situated within the upper reaches of the river valley of the Gelvin and its tributaries, on the northern extent of the Sperrins, about 9km northeast of Dungiven. The soils on the majority of the area are humic rankers, a thin primitive soil derived from the underlying parent material of basic igneous rock. Lying to the south of the site close to the river, the soils have developed into wetter gleys. The grassland is composed of seven field parcels sloping from northeast to southwest with associated areas of scrub and woodland downslope along the river valley floor. The combination of topography and the related soil hydrology has resulted in a relatively complex range of grassland communities. These vary from dry to wet, and from moderately base-rich to acid grassland types. Often these differences in type are evident over quite small areas and locally form mosaics with other semi-natural vegetation types, for example, fen meadow, rush pasture and where drier conditions exist, lowland meadow.