Purple moor-grass & rush pastures are marshy grasslands that occur on acidic, poorly drained soils in lowland areas that receive high levels of precipitation (NIEA, 2005). They contain a mixture of grasses, sedges, rushes & herbs characteristic of grasslands, wetlands & heathlands.
- Site: Mosaic of various habitats
- Soil: Water-logged soils, nutrient-poor
- Main species: Characteristic grass & rush species
- UK: 56,000 ha
- NI: 18,700 ha
- Purple moor-grass & rush pastures occur where wet grassland has not been improved by agriculture.
- They tend to occur in mosaic form with other habitats such as dry grassland, swamp, wet heaths, scrub & flushes; transitions between these are common.
- Due to the mosaic habitat & species structure, purple moor-grass & rush pastures in Northern Ireland are difficult to define. The NIEA Habitat Action Plan (2005) defines the habitat as grasslands in which purple moor-grass Molinia caerulea and/or tall rushes (Sharp-flowered rush Juncus acutiflorus) dominate, are colonised by many characteristic plant species depending on the dominants as mentioned above, & have less than 25% cover of scrub or dwarf shrub.
- Purple moor-grass & rush pastures have characteristic vegetation such as purple moor grass & rushes including an abundance of sharp-flowered rush Juncus acutiflorus.
- In NI there are two main plant communities that are variants of those described in the NVC of Great Britain: M24 Molinia caerulea – Cirsium dissectum fen meadow & M23 Juncus effusus/acutiflorus – Galium palustre community “rush pasture”. However, these communities contain species that are not common in Britain such as devil’s-bit scabious Succisa pratensis. The assemblage of plants differs according to the dominant species: Molinia-rich pastures usually include devil’s bit-scabious Succisa pratensis, meadow thistle Cirsium dissectum & tormentil Potentilla erecta, whereas sites dominated by rush include marsh bedstraw Galium palustre & wild angelica Angelica sylvestris.
Current Status in UK & Northern Ireland
- In the UK purple moor-grass & rush pasture covers an estimated 56,000 ha (UK BAP, 1995).
- Northern Ireland holds an estimated third (18,700 ha) of the UK total (NIEA, 2005).
- County Fermanagh holds a large proportion of the NI habitat but it is widely scattered elsewhere.
- The NICS (2000) estimated the coverage of ‘fen meadow’ & ‘species-rich wet grassland’ (which is analogous to purple moor-grass & rush pasture). It showed an overall loss of about a third during a 7 year period (1991-1998).
- Purple moor-grass & rush pastures occur in lowland areas of the Lough Neagh Wetlands. The largest area is on the west shore of Lough Beg (at least 200 ha).
- Purple moor-grass & rush pastures are susceptible to agricultural modification & reclamation throughout their range (UK Biodiversity Steering Group, 1995). Losses in NI occur due to conversion to agricultural grasslands & conifer plantation (NIEA, 2005).
- The NICS (2000) reported that areas of purple moor-grass & rush pasture have been created from other habitats such as agricultural grassland types, broadleaf semi-natural woodland, coniferous plantation, dense & scattered scrub. Yet, much of these ‘gained’ habitats are of lower quality (NIEA, 2005).
- They are threatened from overgrazing, poaching, burning, afforestation, abandonment, habitat fragmentation, air pollution, climate change, agricultural improvement, infilling & planning developments.
- Antrim Hills
- Glenarm Woods
- Grangemore [Bann Estuary]
- Lough Beg
- Rathlin Island Ballycarry
- Rathlin Island Ballygill North