| Site of Special Scientific Interest | |
 | |
| Area of Search | Berkshire |
|---|---|
| Grid reference | SU 639 743 [1] |
| Interest | Biological |
| Area | 75.7 hectares (187 acres) [1] |
| Notification | 1986 [1] |
| Location map | Magic Map |
Sulham and Tidmarsh Woods and Meadows is a 75.7-hectare (187-acre) biological Site of Special Scientific Interest west of Reading in Berkshire. [1] [2]
A Site of Special Scientific Interest (SSSI) in Great Britain or an Area of Special Scientific Interest (ASSI) in the Isle of Man and Northern Ireland is a conservation designation denoting a protected area in the United Kingdom and Isle of Man. SSSI/ASSIs are the basic building block of site-based nature conservation legislation and most other legal nature/geological conservation designations in the United Kingdom are based upon them, including national nature reserves, Ramsar sites, Special Protection Areas, and Special Areas of Conservation. The acronym "SSSI" is often pronounced "triple-S I".
Reading is a large historic university and minster town in Berkshire, England, of which it is now the county town. It is in the Thames Valley at the confluence of the River Thames and River Kennet, and on both the Great Western Main Line railway and the M4 motorway. Reading is 70 miles (110 km) east of Bristol, 24 miles (39 km) south of Oxford, 40 miles (64 km) west of London, 14 miles (23 km) north of Basingstoke, 12 miles (19 km) south-west of Maidenhead and 15 miles (24 km) east of Newbury as the crow flies.
Berkshire is a county in South East England. One of the home counties, Berkshire was recognised by the Queen as the Royal County of Berkshire in 1957 because of the presence of Windsor Castle, and letters patent were issued in 1974. Berkshire is a county of historic origin, a ceremonial county and a non-metropolitan county without a county council. The county town is Reading.
Previously known as Pang Valley SSSI, the site is mostly sandwiched between the River Pang and the Sulham Road and includes Broom Copse, Herridge's Copse, Hogmoor Copse, Park Wood, Moor Copse and Barton's Copse. Much of the southern part of the site is the Berkshire, Buckinghamshire and Oxfordshire Wildlife Trust's Moor Copse Nature Reserve. The whole site lies within the North Wessex Downs Area of Outstanding Natural Beauty. [3] [4]
The River Pang is a small chalk stream river in the west of the English county of Berkshire, and a tributary of the River Thames. It runs for approximately 23 kilometres (14 mi) from its source near the village of Compton to its confluence with the Thames in the village of Pangbourne.
The Berkshire, Buckinghamshire and Oxfordshire Wildlife Trust is a wildlife trust covering the counties of Berkshire, Buckinghamshire and Oxfordshire in England.
The SSSI consists of five areas.
| Location | Unit area (Ha) | Main habitat |
| 51°28′13″N1°04′58″W / 51.4704°N 1.0828°W | 15.24 | Acid grassland - lowland |
| 51°27′57″N1°04′43″W / 51.4659°N 1.0786°W | 15.48 | Broadleaved, mixed and yew woodland - lowland |
| 51°27′38″N1°05′04″W / 51.4605°N 1.0844°W | 27.57 | Broadleaved, mixed and yew woodland - lowland |
| 51°27′18″N1°04′49″W / 51.4551°N 1.0803°W | 7.70 | Broadleaved, mixed and yew woodland - lowland |
| 51°27′57″N1°04′59″W / 51.4659°N 1.0831°W | 9.76 | Neutral grassland - lowland |
The site is in a broad valley of unusually varied alluvial loams, gravel terraces and peat deposits, resulting from flooding in late glacial times by an enlarged River Kennet. The variety in soils and topography results in a mosaic of damp copses and seasonally flooded meadow communities, maintained here by a long history of coppicing and sympathetic grassland husbandry. The woodland on the site supports a rich invertebrate fauna including over 300 species of moth. [5]
Alluvium is loose, unconsolidated soil or sediment that has been eroded, reshaped by water in some form, and redeposited in a non-marine setting. Alluvium is typically made up of a variety of materials, including fine particles of silt and clay and larger particles of sand and gravel. When this loose alluvial material is deposited or cemented into a lithological unit, or lithified, it is called an alluvial deposit.
Gravel is a loose aggregation of rock fragments. Gravel is classified by particle size range and includes size classes from granule- to boulder-sized fragments. In the Udden-Wentworth scale gravel is categorized into granular gravel and pebble gravel. ISO 14688 grades gravels as fine, medium, and coarse with ranges 2 mm to 6.3 mm to 20 mm to 63 mm. One cubic metre of gravel typically weighs about 1,800 kg.
Peat, also known as turf, is an accumulation of partially decayed vegetation or organic matter. It is unique to natural areas called peatlands, bogs, mires, moors, or muskegs. The peatland ecosystem is the most efficient carbon sink on the planet, because peatland plants capture CO2 naturally released from the peat, maintaining an equilibrium. In natural peatlands, the "annual rate of biomass production is greater than the rate of decomposition", but it takes "thousands of years for peatlands to develop the deposits of 1.5 to 2.3 m [4.9 to 7.5 ft], which is the average depth of the boreal [northern] peatlands". Sphagnum moss, also called peat moss, is one of the most common components in peat, although many other plants can contribute. The biological features of Sphagnum mosses act to create a habitat aiding peat formation, a phenomenon termed 'habitat manipulation'. Soils consisting primarily of peat are known as histosols. Peat forms in wetland conditions, where flooding or stagnant water obstructs the flow of oxygen from the atmosphere, slowing the rate of decomposition.
