SAC 002346 Brown Bog
SITE NAME: Brown Bog
SITE CODE: 002346
Brown Bog SAC is located 5 km north-west of Longford Town mainly in the townlands of Tully, Lissanurlan and Cartronlebagh. The site comprises a raised bog that includes both areas of high bog and cutover. The bog margins are mainly surrounded by scrub/woodland.
The site was selected as a Special Area of Conservation for active raised bog, degraded raised bog and Rhynchosporion, habitats that are listed on Annex I of the E.U. Habitats Directive. Active raised bog comprises areas of high bog that are wet and actively peat-forming, where the percentage cover of bog mosses (Sphagnum spp.) is high, and where some or all of the following features occur: hummocks, pools, wet flats, Sphagnum lawns, flushes and soaks. Degraded raised bog corresponds to those areas of high bog whose hydrology has been adversely affected by peat cutting, drainage and other land use activities, but which are capable of regeneration. The Rhynchosporion habitat occurs in wet depressions, pool edges and erosion channels where the vegetation includes White Beak-sedge (Rhynchospora alba) and/or Brown Beak-sedge (R. fusca), and at least some of the following associated species, Bog Asphodel (Narthecium ossifragum), Sundews (Drosera spp.), Deergrass (Scirpus cespitosus), Carnation Sedge (Carex panicea).
The site is situated in a drumlin-filled valley and consists of a small raised bog characterised by a central wet depression with quaking mats of bog mosses and tear pools colonised by algae. Water flows through the pools and there is a possible spring located in the bog centre. A flush area occurs in the north. Abandoned cutover is found around the northern, western and north-eastern bog margins. Remnant old deciduous woodland occurs to the north-west.
The site supports typical Midland Raised Bog communities, which include Ling Heather (Calluna vulgaris), Carnation Sedge, Bog-rosemary (Andromeda polifolia) and occasional Cranberry (Vaccinium oxycoccos). The high bog supports extensive quaking carpets of bog mosses including Sphagnum magellanicum, S. papillosum and S. capillifolium. Pools occur frequently and support Sphagnum auriculatum, Bogbean (Menyanthes trifoliata) and Great Sundew (Drosera anglica). Bare pools and algal pools are also found. Hummocks of Sphagnum imbricatum and S. fuscum occur. The high bog is drier around the margins where Ling Heather and lichens (Cladonia spp.) dominate. Scattered Downy Birch (Betula pubescens) occurs in association with the northern flush along with Soft Rush (Juncus effusus).
Quaking flats of Bog Asphodel and bog moss lawns dominate the inter-pool areas of the flush. One pool with obvious water flow supports the Bog Pondweed (Potamogeton polygonifolius). Old cutover is mainly colonised by Gorse (Ulex europaeus), Downy Birch, Scots Pine (Pinus sylvestris) and Purple Moor Grass (Molinia caerulea). In the northwest old deciduous woodland with Downy Birch, Scots Pine, Rowan (Sorbus accuparia) and occasional the Beech (Fagus sylvatica) is found.
There are few landuses associated with this site. There are no high bog drains and only two sets of marginal drains are present in the cutover to the north-west. At present there is no active peat-cutting on the site. A large area of cutover to the east of the site has been recently afforested with Sitka Spruce (Picea sitchensis). The majority of the bog has not been burnt for some time, although recent localised burning has taken place along the southern margin. Overall there has been little damage to this bog, with only small areas of cutover present. Most of the extent of the original peat basin appears to be remaining. However, peat-cutting and burning are the two main threats to the site.
Brown Bog is a site of considerable conservation significance comprising as it does a raised bog, a rare habitat in the E.U. and one that is becoming increasingly scarce and under threat in Ireland. Although the site is small it supports a good diversity of raised bog microhabitats including hummock/hollow complexes, pools and a flush system with surrounding tear pool complex, along with cutover which adds to the diversity and scientific value of the site. Active raised bog is listed as a priority habitat on Annex I of the E.U. Habitats Directive. Priority status is given to habitats and species that are threatened throughout the E.U. Ireland has a high proportion of the E.U. resource of this habitat type (over 60%) and so has a special responsibility for its conservation at an international level.