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Overview of Effects  

The following sites of environmental interest are within the study area of the Scheme. These sites have been considered in the Environmental Statement and, in consideration of the design of the scheme and the mitigation incorporated, there is no noted effect of the Scheme on these sites.

The Alder Bourne

The Alder Bourne, east of Fulmer, is a small river with adjacent meadow, pasture and wooded corridor. It supports a number of species uncommon in Buckinghamshire such as lesser spearwort and tubular water-dropwort (Oenanthe fistulosa). In addition, bluebell, song thrush and spotted flycatcher (Muscicapa striata) are also present.

The Apiary

The Apiary consists of an old orchard, old meadow and a small piece of old woodland. The meadow supports unimproved neutral and calcareous grassland including common spotted-orchid (Dactylorhiza fushsii) and adder's tongue (Ranunculus ophioglossifolius).

Barley Mo Farm Meadow

Barley Mo Farm Meadow is a meadow by the River Colne supporting secondary, somewhat acidic grassland on former sewage settling beds with rough neutral grassland and scrub.

Beechengrove Wood

Beechengrove Wood is a semi-natural ancient woodland situated on lower chalk exposures running down to the River Chess. The wood supports a diverse ground flora with ancient woodland indicators. Flora rare in the County have been recorded on the site, which is within 100 metres of the proposals.

Birch Spring

Birch Spring is a semi-natural ancient woodland including abundant bluebells.

Blackgreen Wood

Blackgreen Wood is an ancient semi-natural high forest with ponds. The area supports a diverse ground flora dominated by bluebells. The ponds are important for protected species, including grass snakes which have been recorded on the site.

Black Park SSSI

Black Park SSSI is situated on the urban fringe of Slough and covers, within Black Park Country Park and Colne Valley Regional Park. The site consists of a variety of habitats comprising dry and wet heath, alder carr, mixed and coniferous woodland and small areas of acid grassland. The heathland and alder carr are of particular importance, as both habitats are very rare in Buckinghamshire. They support specialised communities of plants and animals, including many that are rare or uncommon in the county.

Bottom Wood

Bottom Wood is ancient semi-natural woodland with some planting. Barn owls (of County importance) and marsh tits have been observed here.

Bricket Wood Common

Bricket Wood Common is a large remnant of a formerly extensive lowland heath that has naturally developed on heavy, base deficient soils of the boulder clay. The drainage is poor and wet habitats are characteristic of the site with some drier heath developed on areas with gravel capping. Lowland heath has a limited distribution in south eastern England where it has declined markedly. The site represents an important example in the county as part of the site is ancient woodland of the Pedunculate Oak/Hornbeam type.

Brickfield Spring

Brickfield Spring is semi-natural broad-leaved ancient woodland developed on consolidated plateau gravels over chalk. Castle Lime Works Quarry SSSI
This site covers a disused and partly backfilled chalk quarry where one face has been retained to show the chalk/soil interface. The site is designated a SSSI due to its geological sensitivity and is the finest exposure of clay-filled pipes (resulting from solution of the chalk at the chalk/tertiary sediment interface) in the Chalk Karst of England.

Chalfont Park

Chalfont Park is a meadow, man made lake, mixed woodland and golf course. It contains a number of species uncommon or rare in Buckinghamshire, such as autumn lady's-tresses (Spiranthes spiralis) and common meadow-rue (Thalictrum flavum). Fauna includes mute swan (Cygnus olor), teal (Anas crecca), mallard (Anas platyrhynchos) (all Species of Conservation Concern) and marsh warbler (Acrocephalus palustris) (a Priority Species).

Chorleywood College

Chorleywood College consists of semi-improved and unimproved neutral to acid grassland with some mixed woodland in the south (beech with hazel coppice). A mature hedgerow in the west forms the original boundary with Chorleywood Common. There is also a small orchard, a disused swimming pool and an old dry pond. Protected species are present including great crested newts, badgers and bats.

Chorleywood Common

Chorleywood Common consists of common land supporting a wide variety of habitats including acid communities, neutral grassland, herb-rich chalk grassland and some secondary woodland is also present. Several ponds support five species of amphibians including a good population of great crested newts. County rarities include bogbean (Menyanthes trifoliate) and bladderwort (Utricularia vulgaris).

Chorleywood House Estate

Chorleywood House Estate supports important grassland and woodland areas and associated protected species. The network of woodlands includes ancient and secondary woodland. The grassland areas are composed of semi-improved neutral to acid grassland with chalk grassland in Chorleywood Dell.

Cornflower Field

Cornflower Field south west of London Colney is an arable field with the endangered cornflower (Centaurea cyanus) and nationally scarce spreading hedge parsley (Torilis arvensis) present.

Field by the Lodge

Field by the Lodge, Chandlers Cross is adjacent to the carriageway and composed of semi-improved acid grassland with herb-rich flora. Anthills are present and the site is good for invertebrates with eight species of butterfly recorded.

Frogmore Gravel Pit

Frogmore Gravel Pit consists of in filled gravel workings supporting rough grassland, permanent and temporary pools and scattered willow/hawthorn scrub. Pools and hollows are of considerable importance for freshwater invertebrates and great crested newt. Hyde Lane supports relatively ancient vegetation forming good cover for birds. The lakes and the River Ver to the east of the site support diverse marginal vegetation with good aquatic flora. Common spotted orchid have been recorded.

Gossams and Rush Green Wood

Gossams and Rush Green Wood are mixed woodlands. Some species uncommon in Buckinghamshire are present such as hard fern (Blechnum spicant), including some Buckinghamshire Biodiversity Action Plan species such as heather (Calluna vulgaris). Also present are a number of notable species such as stag beetle which is a globally threatened and declining species; kestrel (Falco tinnunculus); song thrush (Turdus philomelos); lesser whitethroat (Sylvia curruca); blackcap (Sylvia atricapilla); chiffchaff (Phylloscopus collybita); willow warbler (Phylloscopus trochilus); and bullfinch (Pyrrhula pyrrhula).

Great Notley

Great Notley is ancient semi-natural broad-leaved woodland with some large scattered oak standards and smaller standards of ash, cherry (Prunus sp.) and sycamore with hazel coppice below. A pond is present along the western edge. The site is within 100 metres of the current Highway Boundary.

Great Wood

Great Wood is ancient woodland mostly replanted with conifers but with some mature oak, ash and beech, particularly in the southwest corner. The area supports bluebells amongst other ancient woodland indicators.

Greyhound Lane

Greyhound Lane is an old pasture with species rich semi-improved neutral grassland and small patches of scrub.

Harrocks Wood

Harrocks Wood is ancient semi-natural broad-leaved woodland. Nationally important invertebrates have been recorded on the site. The nationally scarce coralroot (Cadamine bulbifera) is also present.

Hawkshead

Hawkshead is part of a complex site comprising both ancient oak/hornbeam woodland and heathland with scrub and secondary woodland. Part of the wood is structurally varied, with high forest and coppice with standards. Oak and ash dominate the canopy with hazel, guelder rose (Viburnum opulus) and midland hawthorn (Crataegus laevigata) in the shrub layer. Flora includes bluebell, yellow pimpernel and relict heathland species include heather and the County rarity creeping willow (Salix repens). The wood is also of importance for fungi and bryophytes.

Holt Wood

Holt Wood is ancient semi-natural hornbeam coppiced woodland with remnant with oak, cherry and beech standards. Some hazel coppice and holly is present in the shrub layer. Pipistrelle bats have been recorded feeding in a sheltered inlet at the southern edge. The western side of the wood has been opened up by the construction of the M1/M25 resulting in loss of trees from windthrow.

Horns Wood

Horns Wood is ancient semi-natural broadleaved woodland, bisected by the M25. The woodland is dominated by sycamore with ash and beech and ground flora is dominated by Ivy.

Job's Wood

Job`s Wood is ancient semi-natural oak/hornbeam coppiced woodland with birch, rowan, holly and some larch. Bluebells are present in the ground flora. There are ditches around the wood with holly/hornbeam hedgerows.

Juniper Hill Wood

Juniper Hill Wood is ancient semi-natural woodland, with some open areas due to wind blow. The ground flora supports ancient woodland indicators like bluebells, wood spurge and early purple orchid (Orchis mascula). There is an old wooded lime pit inside the wood.

Kingcup Meadows

Kingcup Meadows and Oldhouse Wood constitutes an intimate mosaic of habitats adjacent to the River Alderbourne, which includes woodland, unimproved pastures and semi and unimproved meadowland. The fields are comprised of dry grassland, wet grassland and areas of fen and swampy vegetation. Unimproved grassland and wetland habitats have declined nationally as a result of agricultural improvement and are now very scarce within Buckinghamshire. Oldhouse Wood has been managed in the past as coppice with standards and retains a wide range of native trees and shrubs, along with many woodland species indicative of ancient woodland.

The marshy grasslands of Kingcup Meadows support uncommon or rare species in Buckinghamshire such as ivy-leaved crowfoot (Ranunculus hederaceus), marsh ragwort (Senecio aquaticus), blinks (Montia fontana), lesser spearwort (Ranunculus flammula), oval sedge (Carex ovalis) and bristle club-rush (Isolepis setacea).

Ladywalk Wood

Ladywalk Wood is ancient semi-natural broadleaved woodland containing old chalk pits. Bluebell and the scarce green hellebore (Helleborus viridis) are present.

Little Lady's Wood

Little Lady's Wood is a small area of ancient semi-natural woodland. Ancient semi-natural woodland are areas that have retained the native tree and shrub cover, although it may have been managed by coppicing or felling and allowed to regenerate naturally.

Long Spring Wood

Long Spring Wood is a Wildlife Trust reserve situated on clay-with-flints soils. It consists of a small area of semi-natural ancient woodland dominated by oak with ash and hazel. There is a well-developed shrub layer beneath the tree canopy, which is important for birds and mammals. The ground flora supports ancient woodland indicators. Long Wood.

Long Wood is a mixed woodland split by the M25 consisting mainly of conifer plantation and birch. The woodland is mostly immature with some coppice. There is a large whitebeam (Sorbus aria) tree on the northern edge of the wood. The ground flora supports ancient woodland indicators.

Mid Colne Valley

The Mid Colne Valley is of significant ornithological interest, particularly for the diversity of breeding woodland and wetland birds. On the eastern valley slope is one of the last remaining examples of unimproved chalk grassland in Greater London. The ornithological interest of the site is considerable with over 70 breeding and 80 wintering species of bird regularly recorded, including significant numbers of wintering wildfowl. This high diversity reflects the close proximity of the wide range of habitats present: woodland, scrub, grassland, running and standing water, marginal fen and gravel banks.

Moor Mill and Park Street Pits

Moor Mill and Park Street Pits consist of in-filled gravel workings supporting rough grassland, permanent and temporary pools and scattered willow/hawthorn scrub. The grassland is botanically diverse and common spotted orchid has been recorded. The damp hollows and pools are of considerable importance for freshwater invertebrates, and great crested newt are known to breed here. Hyde Lane supports relatively ancient vegetation forming good cover for birds. The lakes and the River Ver to the east of the site support diverse marginal vegetation with good aquatic flora.

Moor Mill South

Moor Mill South and Smug Oak Gravel Pit consist of a back-filled gravel pit with a species diverse flora including the nationally scarce greater spearwort (Ranunculus lingua). The County scarce short styled field rose (Rosa stylosa) is present in scrub areas. Great crested newts have been recorded on the site.

Nockhill Wood

Nockhill Wood is an old coppice with standards and excellent boundary ditches on the northeast sides. Bluebell (Hyacinthoides non-scripta), an ancient woodland indicator species, is present on the site.

North Grove Wood

North Grove Wood is an ancient semi-natural oak, ash and beech woodland with hazel and cherry coppice. The western part of the wood has been planted with european larch (Larix decidua). Most of the ground cover is bramble and bracken with bare ground under the coniferous area. The ground flora supports ancient woodland indicators with abundant bluebells and scattered with foxglove, dog's mercury and wood millet (Milium effusum).

Oakend Wood

Oakend Wood is ancient woodland supporting mature pedunculate oak (Quercus robur), beech (Fagus sylvatica), birch (Betula sp.) with a holly (Ilex aquifolium), rowan (Sorbus acucparia) and hazel (Corylus avellana) coppice understorey. It supports a number of species of Conservation Concern including goldcrest (Regulus regulus), firecrest, nuthatch (Sitta europaea) and bullfinch (Pyrrhula pyrrhula). Denham Marsh Wood is acid woodland situated within Oakend Wood.

Old Rectory Meadows

Old Rectory Meadows provide an exceptional habitat on the outskirts of London. They lay either side of the River Misbourne on alluvium and contain a range of grassland types, notably base-rich and poor marsh, wet alluvial meadows and water meadows with grazed wet and damp meadows, as well as alder carr woodland. The soil is calcareous alluvial clay.

Pheasants Wood

Pheasants Wood is a large woodland site bisected by the M25. The southern part is of ancient origin and the northern part is largely secondary.

Redwell Wood

Redwell Wood is a complex site comprising both ancient woodland of the pedunculate oak/hornbeam type and heathland, together with well developed scrub and secondary woodland. The combination of ancient woodland and heathland habitats is uncommon in the county and both types have been greatly reduced in extent locally and nationally. 

Sarratt Bottom

Sarratt Bottom is an area of alluvial meadow beside the River Chess. The site is an example of damp, species rich, unimproved neutral grassland, traditionally managed for grazing. It is characteristic of lowland Britain, however agricultural change has severely reduced the extent of this habitat nationally. In Hertfordshire this habitat is very scarce.

Scrubbs and Blunts Wood

Scrubbs and Blunts Wood is an semi-natural ancient woodland site replanted with conifers, mainly larch, in the north with mixed plantation in the centre. The southern section is still broadleaf woodland. Bluebell is abundant throughout.

Shenley Lodge Farm Wood

Shenley Lodge Farm Wood is ancient semi-natural woodland with hazel coppice. Ground flora dominated by bluebells (Hyacinthoides non-scripta) and dog's mercury (Mercurialis perennis).

Smug Oak Lane

Grassland south of Smug Oak Lane consists of two parallel fields either side of a stream supporting fairly rank semi-improved neutral grassland. Floristically rich areas support species such as hardheads (Centaurea sp.), oxeye daisy and lady's bedstraw (Galium verum). The small, dammed stream has good aquatic vegetation with reed sweet-grass (Glyceria maxima) and water plantain (Alisma plantago-aquatica).

Templepan Wood

Templepan Wood is ancient semi-natural broad-leaved woodland in the south with conifer plantation in the north. The ground flora supports ancient woodland indicators including abundant bluebells.

Tenements Farm

Tenements Farm consists of buildings and surrounding habitat important for protected species.

Valley Road

The Valley Road area consists of buildings and a surrounding habitat (Solomons Wood) important for protected species.

Welling Grove

Welling Grove is ancient semi-natural woodland. The ground flora is mostly bracken (Pteridium aquilinum) and bramble with some ancient woodland indicators including abundant bluebells.

Whippendell Wood

This is an ancient woodland site in the clay-with-flints region set in a predominantly urban and agricultural setting. There are large areas of retained semi-natural vegetation and a complex of woodland habitats is present on the pebble clays and sandy soils with Oak/Hazel/Ash and Oak/Hornbeam being the major stand types. These woodland types are scarce nationally and also within Hertfordshire.

Winch Hill Wood 

Winch Hill Wood is ancient oak/hornbeam woodland dissected by the M1 motorway. The woodland consists of derelict hornbeam coppice with standards of mature oak, cherry, ash and birch. In addition the wood has a series of chalk pits with mature beech and elder (Sambucus nigra) scrub. There is an ancient woodland bank and ditch with an old hornbeam hedge.