NVC community SD17 is one of the 16 sand-dune communities in the British National Vegetation Classification

British National Vegetation Classification

The British National Vegetation Classification or NVC is a system of classifying natural habitat types in Great Britain according to the vegetation they contain....

 system.

It is one of five communities associated with dune slacks.

It is a very localised community. There are four subcommunities.

Community composition

The following constant species are found in this community:

• Creeping Bent
  Agrostis stolonifera
  Agrostis stolonifera is a perennial grass species in the Poaceae family. It is stoloniferous and may form mats or tufts...
  
   (Agrostis stolonifera)
• Common Sedge (Carex nigra)
• Silverweed
  Silverweed
  Argentina anserina, also known as Common Silverweed, Silverweed Cinquefoil or just "silverweed", is a flowering perennial plant in the rose family Rosaceae. It is native throughout the temperate Northern Hemisphere, often on river shores and in grassy habitats such as meadows and road-sides...
  
   (Potentilla anserina)
• Pointed Spear-moss (Calliergon cuspidatum)

No rare species are associated with the community.

Distribution

This community is found in two areas - on the east coast, from Spurn Point to northwest Norfolk

Norfolk

Norfolk is a low-lying county in the East of England. It has borders with Lincolnshire to the west, Cambridgeshire to the west and southwest and Suffolk to the south. Its northern and eastern boundaries are the North Sea coast and to the north-west the county is bordered by The Wash. The county...

, and on the dunes of Liverpool Bay

Liverpool Bay

Liverpool Bay is a bay of the Irish Sea between northeast Wales, Cheshire, Lancashire and Merseyside to the east of the Irish Sea. The bay is a classic example of a region of freshwater influence...

.

Subcommunities

There are three subcommunities:

• the Festuca rubra - Ranunculus repens subcommunity
• the Carex flacca subcommunity
• the Caltha palustris subcommunity
• the Hydrocotyle vulgaris - Ranunculus flammula subcommunity