Vallis Vale

Also within

Somerset County

Condition (Natural England)

Habitats

Ancient woodland, Fast flowing river and stream

Geology & landscape

Geological Period: Carboniferous, Jurassic · Rock Type: Carboniferous Limestone, Limestone

Birds & fish recorded

Birds

Description

Area, 23.9 ha. 59.1 ac. Description Vallis Vale is an ancient woodland site and supports an ash / wych elm stand type with a restricted distribution in Britain. The Vale is the meeting point of the Hells Stream and the Egford Brook. The two watercourses flow through deeply dissected wooded valleys where shallow calcareous soils have developed on the underlying Carboniferous Limestone strata. The steep slopes support an ancient woodland stand of the local ash wych elm type. The canopy is dominated by ash Fraxinus excelsior. Pedunculate oak Quercus robur and small leaved lime Tilia cordata are less frequent. Although most of the wych elm Ulmus glabra standards have been killed by Dutch Elm disease, many of the rootstocks remain alive and in places new growth is vigorous. Field maple Acer campestre and hazel Corylus avellana dominate the understorey which also includes spindle Euonymus europaeus, privet Ligustrum vulgare, dogwood Cornus sanguinea and guelder rose Viburnum opulus. Ground flora species usually restricted to ancient woodlands include wood spruge Euphorbia amygdaloides, wood anemone Anemone nemorosa, yellow archangel Lamiastrum galeobdolon and Solomon’s seal Polygonatum multiflorum. Dog’s mercury Mercurialis perennis or bramble Rubus fruticosus are dominant in drier areas and ramsons Allium ursinum in wetter parts. Valley alder wood characterised by alder Alnus glutinosa and goat willow Salix caprea occurs along the streams. Bankside vegetation includes angelica Angelica sylvestris, meadowsweet Filipendula ulmaria and yellow flag Iris pseudacorus. Vallis Vale supports large populations of banded agrion Calopteryx splendens and demoiselle agrion Calopteryx virgo. Breeding birds include kingfisher Alcedo at this, dipper Cinclus cinclus and kestrel Falco tinnunculus. Greater horseshoe bats Rhinolophus ferrumequinum have also been recorded in the site. Vallis Vale is one of the few Somerset sites where crayfish Austropotamobius pallipes occur. Geological Vallis Vale exposes some of Britain’s most classic rock outcrops, exhibiting several of the most easily demonstrated examples of angular unconformity available. The famous inferior Oolite – Carboniferous Limestone unconformity first described by Conybeare and Buckland is of great historical significance. The site also contains other examples of the overstep and burial of the Carboniferous Limestone ‘Mendip Island’ in Lower and Middle Jurassic times. A nationally important research and educational locality, of great renown for the part it has played in the historical development of geological science. Hapsford Bridge is a key Rhaetic site showing Westbury, Cotham and Langport Beds in the most extensive sections in the east Mendips. Clays and, sometimes bored, conglomerates with Atreta intustriata overlie bored and encrusted Carboniferous Limestone with angular discordance. The liverwort Naiadita occurs in the Cotham Beds here and Thecodontosaurus was discovered by Charles Moore at this locality in the last century. An historic and important Rhaetian section showing the first effects of the ‘Jurassic’ transgression.

Species mentioned

Plant communities