Selborne Common is a biological Site of Special Scientific Interest west of Selborne in Hampshire. It is a Nature Conservation Review site, Grade I, and is part of the East Hampshire Hangers Special Area of Conservation. It is managed by the National Trust. Topography The Common occupies the crown of Selborne Hill, an easterly guardian of the Hampshire Downs. The highest part has an elevation of above sea level. The southerly and westerly flanks slope away gently; on the other sides the contours are steeper. The steepest slope of all, with a maximum gradient of about 50%, overlooks the village and is called "Selborne Hanger". To the west of this is Coneycroft Hill, which in places is almost as precipitous. Between Selborne Hanger and Coneycroft Hill is a deep dell. Geology The soil on the Common consists of clay with flints, overlying the chalk of which the South Downs are made. The watercourses are underground and discharge into the Oakhanger Stream, flowing north-eastwards, and the Caker Stream, flowing northwards. Both ultimately join the River Wey. Flora The steepest slopes are clad in ancient beechwood (Fagus sylvatica): a "hanger", in East Hampshire, is just such a beechwood. The plateau is occupied by more beechwood, mixed with other broad-leaved species such as English oak (Quercus robur), ash (Fraxinus excelsior) and hawthorn (Crataegus monogyna), and in places is scrubby. A small part of the plateau comprises open grassland with scattered gorse (Ulex europaeus) and stands of bracken (Pteridium aquilinum). Other, smaller areas of chalk grassland have recently been recreated elsewhere. The Common is noted for its wild flowers, with thriving communities of yellow archangel (Galeobdolon luteum), wood spurge (Euphorbia amygdaloides) and wood anemone (Anemone nemorosa). Spurge-laurel (Daphne laureola) is sparsely but widely distributed. The Common is also home to such interesting species as stinking hellebore (Helleborus foetidus), green hellebore (H. viridis ssp. occidentalis), bird's nest orchid (Neottia nidus-avis), violet helleborine (Epipactis purpurata), the extreme rarity E. x schulzei (first British record here, 1931), and green-flowered helleborine (E. phyllanthes). Fauna Various rare molluscs and insects have been recorded. Butterflies on the Common include the Duke of Burgundy (Hamearis lucina), silver-washed fritillary (Argynnis paphia) and purple emperor (Apatura iris). The avifauna includes most of the species typical of broad-leaved woodland in southern England, such as sparrowhawk (Accipter nisus), stock dove (Columba oenas), tawny owl (Strix aluco), European green woodpecker (Picus viridis), great spotted woodpecker (Dendrocopos