The rolling ridges and plateaux of the Culm extend across north-west Devon and north-east Cornwall, reaching from the foot of Dartmoor in the southwest and the edge of the Cornish Killas in the west, to the spectacular Atlantic coast of cliffs and sandy beaches in the north. North-eastwards they meet the Exmoor landscape and stand high above the Devon Redlands. The open, often treeless, ridges are separated by an intricate pattern of small valleys forming the catchments of the Rivers Taw, Torridge and Mole. This is largely a remote and sparsely populated landscape.
The geodiversity of the area is of national importance. Dramatically folded rocks – seen particularly around Hartland – allow access to and interpretation of the geodiversity, and create a distinctive coastline. The exceptional beauty, tranquillity and wildness of the coast are reflected in its designation as both the North Devon Area of Outstanding Natural Beauty (AONB) and a Cornwall AONB, and recognition as Heritage Coast. The UNESCO North Devon Biosphere Reserve forms a focus for the wealth of biodiversity found across the area. Similarly, this rich resource is reflected in the designation of four Special Areas of Conservation (SAC) within the area: the Tintagel–Marsland–Clovelly Coast SAC and the Culm Grasslands SAC. Dunsdon National Nature Reserve (NNR) provides access to and interpretation of the internationally important Culm grassland habitat.
The area is a popular visitor destination, providing many leisure and recreation opportunities. The South-West Coast Path National Trail provides access to dramatic cliffs and remote coves. Clovelly and Hartland Point are examples of popular coastal destinations. Inland, a more tranquil, pastoral landscape provides for quiet leisure and recreation, walking, cycling and riding.
Influenced by the Atlantic climate, impermeable geology and clay soils, the area produces lush grasslands and, subsequently, notable volumes of meat and dairy produce. Biodiversity, geodiversity, tranquillity and a distinct sense of place are key components of the landscape. Changes in climate, localised development pressures – most prominently wind energy development – and changes in agricultural practices and regimes, are most likely to result in changes in this otherwise deeply rural, pastoral landscape.
Statements of Environmental Opportunity
- SEO 1: Seek to maintain, enhance and join up the distinctive and internationally important areas of Culm grassland, with their simple patterns of fields, hedgebanks, woodlands, rivers and tributaries, and their strong links to past land use and settlement. This will bring benefits in terms of reducing soil erosion, improving soil quality and water availability, regulating water flow, promoting the interpretation of the historic environment, enhancing biodiversity and supporting pastoral farming.
- SEO 2: Safeguard the rich geological record and current geomorphological processes, particularly along the internationally important coastline. Where possible, allow the unimpaired operation of natural coastal processes, resulting in the creation of new habitats, conserving and enhancing landscape character, and benefiting biodiversity and the historic environment.
- SEO 3: Protect open views and the simple, austere character of the landscape and seascape, enhancing access to and interpretation of the wealth of natural and heritage assets, and recreational opportunities, throughout the area – including the South West Coast Path.
The Culm NCA provides a wide range of benefits to society. Each is derived from the attributes and processes (both natural and cultural features) within the area. These benefits are known collectively as ‘ecosystem services’. The predominant services are summarised below.
Provisioning services (food, fibre and water supply)
Food provision: The area is characterised by its dairy production, and is also a producer of quality beef cattle, including traditional Red Ruby, and lamb. The sections of arable land in the south-east of the NCA also contribute to food provision through cereal production.
Timber provision: The relatively high proportion (13 per cent) of woodland in this area is not reflected in the availability of timber. Much of the woodland is located in the very difficult to access coastal combes and steep-sided valleys of the Taw and Torridge; however, plantations at the centre of the area have the capacity to produce both hard and soft wood in significant volumes.
Biomass energy: Existing woodlands and hedgerows are being brought under sympathetic management with potential for some biomass production as a by-product of commercial timber production. Opportunities for growing miscanthus do exist, where not in conflict with Culm grassland sites and belowground heritage assets, with high potential yields identified across the area.
Water availability: Most of the area is classified as having additional water available for abstraction, although the NCA contains some areas that either have no water available for additional abstraction or are already over-abstracted.
There are two reservoirs in the NCA: Upper and Lower Tamar Lakes, and Roadford Reservoir. In the Taw and Tamar catchments the main abstractions are for public water supply, agriculture, aquaculture and hydroelectric power (although in the latter case only small sections of river experience reduced flow). Within the North Cornwall catchment, the main abstraction (making up 50 per cent) is for hydroelectric power generation, followed by aquaculture.
Regulating services (water purification, air quality maintenance and climate regulation)
Regulating soil erosion: The majority of soils in this NCA are medium to heavy soils that are at only limited risk of erosion. They are most at risk on steeper slopes under cultivation, and as a result of high rainfall. The upper reaches of the Tamar within this NCA down to Launceston fall within a Department for Environment, Food and Rural Affairs (Defra) priority catchment area, due to the high rates of sedimentation. The gently-sloping terrain, with its predominantly loamy or slowly permeable clay soils, has moderate to high run-off potential, with rates of surface flow leading to soil erosion and sedimentation within waterbodies.4 In addition, these soils have limited potential for increasing organic matter levels by management interventions, because levels are already likely to be high
Regulating soil quality: The freely-draining, slightly acid, loamy soils, covering 55 per cent of the NCA, have good water infiltration where the soil structure is good. The slowly permeable, seasonally wet, acid, loamy and clayey soils (24 per cent) are easily damaged when wet, and are at risk of causing diffuse pollution and flooding as a result of poor water infiltration. In addition, these soils have limited potential for increasing organic matter levels by management interventions.
Regulating water quality: Groundwater quality across the north and centre of the NCA is good, although there are also large areas with poor groundwater quality. Most rivers within the NCA are of moderate ecological quality, although stretches of the Tamar are considered poor. The upper reaches of the Tamar have been identified as a Defra priority catchment.
Regulating water flow: Impermeable rocks and steep gradients in the upper catchments give the rivers a ‘flashy’ nature, which can cause rapid flooding downstream after heavy rainfall, particularly when this coincides with high tides in the estuaries and at outfalls.5 There is high fluvial flood risk along the coast in East Cornwall (as demonstrated by the 2004 flooding of Boscastle, on the border between this NCA and the Cornish Killas, and the 2012 flooding of Clovelly), where the watercourses rise on high ground in small catchments and flow rapidly downhill in deep, narrow valleys directly to the sea.6
Regulating coastal flooding and erosion: Rates of cliff erosion are generally slow and beaches are likely to maintain their current form with continued inputs. Localised problems may occur where cliff erosion undermines the South West Coast Path and coastal car parks. The Shoreline Management Plans for both Cornwall and the Isles of Scilly and for North Devon have recommended active and uninterrupted erosion, to allow natural processes to evolve along much of the coast.
Cultural services (inspiration, education and wellbeing)
Sense of place/inspiration: A sense of place is derived from the pastoral character: open, rolling ridges, intimate river valleys and the distinctive Culm grasslands on commons, unenclosed ground and unimproved pasture, with
blocks of both deciduous and coniferous woodland. The coast is defined as Heritage Coast and falls within the North Devon AONB. It is dramatic and striking, varying from low-lying levels, long sandy beaches and sand dunes, to high cliffs and sheltered coves, and incorporating picturesque, traditional fishing villages.
Sense of history: There is a wealth of visible prehistoric remains, including bronze-age barrows and prominent hill forts. Medieval wayside crosses are another characteristic element of the landscape, together with a high proportion of medieval houses by national standards related to the medieval pattern of dispersed settlement and early enclosure. Settlement is simple and timeless in character.
Tranquillity: The area remains a national ‘island of tranquillity’, largely undisturbed by major development or roads. Only a small proportion (1 per cent) of the area is urban and only local intrusion occurs around the few towns and adjacent to the few major roads.
Recreation: Recreational opportunities are provided by 112 km of the South West Coast Path National Trail, the National Cycle Network, and numerous regional routes including the Tamar Trail, Tarka Trail, Two Castles Trail, Two Moors Way, West Devon Way and Ruby Trail.
Biodiversity: Some 3,500 ha of the NCA, or 1.2 per cent, is designated as a Site of Special Scientific Interest (SSSI), and there are four Special Areas of Conservation (SAC) within the area. Almost 6,000 ha of the NCA are covered by Biodiversity Action Plan (BAP) priority woodland – upland oak, lowland mixed deciduous, lowland beech and yew, and wet woodland. There are almost 3,000 ha of purple moor grass and rush pasture – this is one of the last strongholds of Rhôs pasture or Culm grassland in Britain. The area boasts internationally important populations of marsh fritillary butterfly, and nationally important populations of willow tit and dingy mocha moth. The rivers in the area, the Taw, Torridge and Tamar, provide important habitats for salmonids, and also the most southerly population of freshwater pearl mussel. The coastal fringe of the NCA is important for maritime cliff and slope BAP habitat, consisting of steep (often wooded) slopes and important geological exposures.
Geodiversity: The underlying geology of the area determines and influences the soils, drainage, and many of the habitats and human activities found across the area. The ability to observe, record and interpret geological formations and geomorphological processes, particularly along the coast, is an important contribution to education. Dramatically folded strata are exposed along much of the coastline and this is one of the most distinctive elements of this landscape.