22. WOODED HILLS
Regional Character Areas
Upper Thames Vale, Corallian Ridge.
This landscape type covers the wooded hills at Wytham, Arncott and Graven Hills.
This is a landscape of prominent hills with large blocks of ancient woodland and small grass fields.
• Steep-sided, isolated hills in an otherwise low-lying landscape.
• Large, interlocking blocks of ancient woodland.
• Mixed land uses, but dominated by pastureland.
Geology and landform
The hills are made up of corallian limestone, and they contrast sharply with the surrounding low lying Oxford Clay. For example, Wytham Wood to the west of Oxford is around 150 metres high, approximately 70 metres higher than the adjacent Thames valley.
Land uses and vegetation
Woodland is the dominant and unifying feature of this landscape type. The steep slopes have probably discouraged wholesale clearance of woodland in the past and, as a result, large blocks of ancient woodland dominated by oak, ash and sycamore have survived. On Wytham Hill, the woodlands are extensive and consist of large, interlocking blocks. On Arncott Hill they are also large, but are much more discrete and separate, and often interspersed with scrub. Long-distance views are frequently framed by these dominant woodlands.
The lower slopes of Graven and Arncott Hills are predominantly used for military purposes and have several depots in their grounds. The remaining undeveloped areas throughout the landscape type are used for agriculture, with pastureland being the dominant land use, particularly in places such as Wytham Park. Outside the park, on Wytham Hill, there are large arable fields enclosed by hawthorn hedges.
The scale of the landscape is characterised by large blocks of woodland enclosing small grass fields. This is particularly obvious on Graven and Arncott Hills. On Wytham Hill, the woodlands are complemented by the large, enclosed arable fields. The pattern of hedgerows and hedgerow trees is less significant, except at Wytham Hill where there is a stronger network which links the woodlands and provides visual unity to the farmed landscape. These hedges also have mature oak and ash trees.
The settlement pattern is characterised by the small, nucleated villages of Arncott and Wytham at the foot of their respective hills, along with a few dispersed farmsteads. Wytham village, with its limestone buildings, is the only village where the local vernacular character remains strong.
There is a large army depot at the foot of Graven Hill.
This area is characterised by prominent hills with large blocks of ancient semi-natural woodland and, predominantly, medium-sized grass fields.
• Ranging from low to medium-high bioscores.
• Priority habitats include ancient semi-natural woodland and calcareous grassland.
This is a relatively small landscape type, occupying around 0.4% of the rural county. It includes Graven Hill and Upper Arncott to the south of Bicester and Wytham Wood to the west of Oxford. It supports a limited range of locally important habitats including semi-improved grassland, species-poor hedgerows with trees and tree-lined watercourses. Other important habitats include parkland, ancient semi-natural woodland and the main priority habitat is calcareous grassland.
LOCAL CHARACTER AREAS
A large block of ancient semi-natural oak and ash woodland dominates the hilltop and small grass fields occupy the lower slopes. Field boundaries are visually insignificant.
However, it is the large army depot at the foot of the hill that dominates this area.
Apart from the ancient semi-natural woodland, only the semi-improved grassland and species-poor hedges with trees contribute to the overall biodiversity of this area.
B. Arncott Hill (UT/49)
A medium-sized block of ancient semi-natural oak and ash woodland covers the hilltop and slopes. It is surrounded by thick blackthorn and hawthorn scrub. The remaining part of the hill is characterised by small grass fields enclosed by woodland and low, gappy hedges dominated by hawthorn and blackthorn with scattered mature trees of oak and ash.
Apart from the ancient semi-natural woodland, this area only supports a few locally important habitats including semi-improved grassland, species-poor hedges with trees and dense scrub.
C. Wytham Hill (CR/12)
Wytham Hill is dominated by large, interlocking blocks of ancient semi-natural oak and ash woodland. Other land uses are mixed, generally being a combination of small grass fields and larger arable fields. They are largely enclosed by the woodland and tall, intact hawthorn hedges with scattered hedgerow trees of oak, ash and dead elm. At the eastern side of the hill there is Wytham Park with its sheep-grazed pasture.
This area is dominated by Wytham Wood, a large block of ancient semi-natural woodland, and Wytham Park with mature trees and pasture. Wytham Wood is around 325 ha and is generally in favourable condition and management. It is a mix of woodland, wood pasture, common land and species-rich limestone grassland. It also has a number of small ponds and an area of fen.
FORCES FOR CHANGE
• In places, such as Arncott Hill, the hedgerows are often low, gappy and in decline whereas at Wytham Hill they tend to be tall, thick and overgrown.
• Some of the pasture at Wytham Park has been converted into arable land.
• There is the significant visual impact of the large scale military depot at the foot of Graven Hill. There are also military buildings at the foot of Arncott Hill but they are less prominent.
Conserve and strengthen the pattern of ancient semi-natural woodlands, pasture, hedgerows and hedgerow trees.
• Promote the sustainable management of existing woodland to safeguard its long-term survival.
• Strengthen the field pattern by planting up gappy hedges using locally characteristic species such as hawthorn, and hedgerow trees such as oak and ash.
• Promote environmentally-sensitive maintenance of hedgerows, including coppicing and layering when necessary, to maintain a height and width appropriate to the landscape type.
• Enhance and strengthen the character of tree-lined watercourses by planting willows and ash and, where appropriate, pollarding willows.
• Conserve the surviving areas of permanent pasture and promote arable reversion to grassland, particularly within areas of parkland.
• Minimise the visual impact of intrusive land uses with the judicious planting of tree and shrub species characteristic of the area. This will help to screen the development and integrate it more successfully with its surrounding countryside.
Ensure that all surviving priority habitats are safeguarded, in favourable condition and management, and enhanced to satisfy the actions and targets identified within the relevant habitat and species action plans. Safeguard, maintain and enhance all locally important habitats in a way which is appropriate to the landscape character of the area.
• There are a number of important and priority habitats including ancient semi-natural woodland, parkland, calcareous grassland, species-rich ditches and fen. Much of it falls within the local character area of Wytham Hill and has been designated as a Site of Special Scientific Interest.
• The priority must be to ensure that all these sites are in favourable condition and management by formal agreement, where appropriate, between the landowner and English Nature.
• Maintain and strengthen pattern of ancient semi-natural woodlands, pasture and hedgerows.
• Ensure that all priority habitats are in favourable condition and management.