Cookstown Farmlands Biodiversity Profile
In the following account of this LCA it should be noted that for consistency, the biodiversity section follows the standard order for all LCAs even though some of the communities discussed later may have more importance for biodiversity than those discussed earlier
Key Characteristics
- woodlands cover c. 2% of the LCA, less than half the percentage for Northern Ireland as a whole; most is broadleaved
- estate woodlands, most of which are at least 'long-established' and parts may be 'ancient', and woodland on cut-over bog, account for most of the woodland
- grassland occupies c. 83% of the land cover of which more than four-fifths is improved pasture of generally low biodiversity
- no heathland and no intact lowland bog; it has all been cut-over and several bogs have been colonized by woodland
- rivers with Priority Species that are rare in Northern Ireland, particularly the Upper Ballinderry.
Woodlands
Woodlands cover c. 2% of the LCA, less than half the percentage for Northern Ireland as a whole; most is broadleaved woodland with the major areas of conifers in State Forest at Drum Manor Forest and at Lissan. Drum Manor occupies the former Oaklands demesne so that some of the original planting (pre-dating the 1830s) remains, but most is mixed planting in a complex arrangement of compartments and forest plots; Norway spruce, Japanese larch, beech and oak are the most common species with some pure compartments of Sitka and Norway spruce. The coniferous woodland at Lissan also occupies part of the demesne and indeed land that was under woodland in the 1830s. Both of these forests therefore have elements of woodland that is at least 'long-established'; the OS Memoir from the 1830s describes Lissan as having 'a great deal of old timber together with several young plantations of Scotch fir and oak' and current evidence suggests that there is at least somr 'ancient' woodland. The Lissan River today is lined by a great variety of trees including, beech, oak and lime, plus specimen trees like redwood, London plane, monkey puzzle and yew. At Lissan, Sitka spruce and Japanese larch are dominant in the State Forest, but there are compartments of Scots pine/beech and oak.
Drum Manor and Lissan are two of several present and former estates (lowland woodland pastures and parkland) that together account for the majority of the woodland in the LCA. In particular, there is a series along the Killymoon River that includes Killymoon Castle, Loughry College, Desertcreat and Tullylagan Manor. Others include Orritor, Lissan Rectory, Rockdale and Bloomhill. Almost all of these were planted by the 1830s and the woodlands are at least 'long-established'; however, as some estates are from the seventeenth century and in some cases have incorporated semi-natural parts (damper areas with alder and willow and steep slopes with ash and scrub) there may be elements of 'ancient woodlands' and could include plants in the herb layer, epiphytic mosses and lichens restricted to such woodlands. Characteristic species in the estates include a dominance of beech with oaks, ash and sycamore in addition to specimen trees (both broadleaved and conifer) scattered through the park. Typically laurels and rhododendron form a dense understorey.
Tirnaskea Wood is also a woodland associated with an old estate, but whilst some of the trees are of estate planting origin, much of the wood has a semi-natural element characterised by the rich ground flora and dominance of native trees. The main non-native trees include beech and western red cedar with rhododendron, cherry laurel and Portuguese laurel. Elsewhere, there are ash, oak, willow, hazel and some wych elm. Holly, blackthorn and hawthorn are frequent in the understorey and the rich flora includes wood anemone, wood sorrel, pignut, goldilocks buttercup, early-purple orchid, common-dog violet and primrose. The nearby Tullyreavy Wood was also present in the 1830s and referred to as the 'Oak Wood'.
Apart from estates, the other main location for woodland is on former cut-over bogs. These are scattered through the LCA, in the south and west lying between drumlins and in the east on broader flat areas alongside tributaries of the Ballinderry. In most cases the woodlands are semi-natural with abundant birch on the drier parts and willow and alder forming wet woodland around the edge where peat has been removed to deeper levels. However, even the bogs have not escaped 'landscaping' (predominantly nineteenth century) so that there are planted stands that include conifers.
Grassland and Arable
Grassland occupies c. 83% of the land cover of which more than four-fifths is improved pasture. Most of the rough grassland is associated with the outskirts of Cookstown and around large sand pits and quarries, but some is damp grassland between drumlins that remains poorly drained. This is usually species-poor grassland with clumps of rushes, but in the wettest parts may become more marshy grassland where rushes, sedges and meadow sweet are common.
Improved pastures generally have low biodiversity as a result of relatively intensive management. Some of the pastures are sown grasslands dominated by ryegrass and few other species - low biodiversity is in-built. Other grasslands have been converted to improved pastures through management. High levels of grazing or repeated cutting for silage, high inputs of fertilizers and slurry, and selective herbicides serve to reduce diversity of both flora and fauna.
Arable land (includes grass re-seeding), which accounts for about 10% of the land cover, is mainly in the south and east of the LCA where, apart from the floodplains, soils are well-drained brown earths.
Biodiversity in areas of improved pastures and arable is often concentrated in hedgerows. Indeed, they may be the most significant wildlife habitat over much of lowland Northern Ireland, especially where there are few semi-natural habitats. Hedgerows are a refuge for many woodland and farmland plants and animals. In this LCA hedgerows are the dominant field boundary, are well treed and because fields are generally not large, the intensity of hedgerows gives them importance to biodiversity. However, in the east of the LCA there is more arable farming and more intensive grassland agriculture; here there is some field amalgamation. In some wetter areas ditches form the field boundaries.
Although farmland dominates the LCA, the inter-mix of habitats (improved grassland, damp grassland, arable, hedges and woodlands) has led to the presence of several Priority Species of birds - those recorded include linnet, song thrush, reed bunting, skylark, bullfinch, curlew and spotted flycatcher.
Heaths and Bogs
There are no heaths in the LCA and no intact lowland raised bog; all the lowland bog has been cut-over in the past and in many instances the bogs have been colonised to form woodland (see above).
Wetlands and Lakes
There are no significant areas of fen and no surveyed lakes that have been classified as of importance to biodiversity. However, the Upper Ballinderry River has been recognised as one of the most important rivers in Northern Ireland for rare aquatic species (Upper Ballinderry River SAC, Upper Ballinderry River ASSI). It is of particular importance for the freshwater pearl mussel as it is one of the few rivers in Northern Ireland that still retains a significant and viable population of this rare shellfish. In addition, the river supports a good range of native fish species, including brook lamprey and brown trout. Otter and kingfishers are present along the length of the river. The middle reaches also have stream water-crowfoot and river water-crowfoot as does the Ballymully.
Key Issues
General actions for UK and NI Priority Habitats and Priority Species are detailed in the Habitat Action Plans and Species Action Plans.
WOODLANDS
Issue: low woodland cover but with significant estate woodland of potentially high
biodiversity value
Actions:
- enhance the biodiversity value of demesne/parkland woodland through control of grazing and felling; by encouraging planting of saplings of the standard trees; by preventing further loss of parkland; by retention of fallen and veteran trees (particularly for bryophytes, ferns, fungi and fauna)
- study of the history and ecology of demesne and other broadleaved woodlands particularly any ancient and long-established is required to further knowledge on biodiversity and as a key to future management
- encourage control of grazing in broadleaved woodlands along streams to foster regeneration and if necessary, encourage replanting of canopy species
- encourage planting of native broadleaved woodlands, through appropriate grant schemes, to improve woodland cover
- protect woodland on cut-over bog from loss and damage (clearance, dumping and land-fill, fly-tipping, drainage)
GRASSLAND AND ARABLE
Issue: poor biodiversity of farmland
Actions:
maintain and improve field boundaries especially hedgerows. This may be achieved through adoption of correct cutting cycles; hedge laying and replanting where necessary; leaving saplings uncut to develop into hedgerow trees; avoidance of spraying with fertilizers, slurry, herbicides; provision of wildlife strips and conservation headlands around fields; and limitation of field amalgamation
encourage (through participation in Environmental Schemes) adoption of less intensive management of pastures to allow reversion to more species-rich grassland and protect areas of species-rich grassland and damp grasslands
maintain and enhance floodplain grassland by restricting field or arterial drainage
leave stubble over winter, rather than autumn ploughing, to increase food resources for farmland birds; spring sown cereals are beneficial to breeding farmland birds.
WETLANDS
Issue: rivers with Priority Species rare in Northern Ireland
Actions:
- protect water quality of rivers through nutrient management, thus
- promote and encourage existing good farming practices so that streams are not polluted by run-off from agricultural land or seepage from silage pits
- continued monitoring of streams below industrial plants and sand pits/quarries
- monitor streams in relation to expansion of rural/urban housing and associated septic tanks/sewage treatment plants
