British NVC community OV18 (Polygonum aviculare - Chamomilla suavolens community) is one of the open habitat

Vegetation of open habitats in the British National Vegetation Classification system

This article gives an overview of the plant communities formed by vegetation of open habitats in the British National Vegetation Classification system.-Introduction:...

 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 six communities characteristic of gateways, tracksides and courtyards.

This community is found throughout the lowlands and upland fringes of Britain on loamy and sandy soils that are disturbed or moderately trampled.

There are two subcommunities.

Community composition

The following constant species are found in this community:

• Shepherd's-purse (Capsella bursa-pastoris)
• Scented mayweed (Matricaria chamomilla) (syn.
  Synonym (taxonomy)
  In scientific nomenclature, a synonym is a scientific name that is or was used for a taxon of organisms that also goes by a different scientific name. For example, Linnaeus was the first to give a scientific name to the Norway spruce, which he called Pinus abies...
  
   Chamomilla suavolens)
• Perennial rye-grass (Lolium perenne
  Lolium perenne
  Lolium perenne, common name Perennial Ryegrass, is a grass from the family Poaceae. It is native to Europe, Asia and northern Africa, but is widely cultivated and naturalised around the world.-Description:...
  
  )
• Annual meadow-grass (Poa annua
  Poa annua
  Poa annua, or annual meadow grass , is a widespread low-growing turfgrass in temperate climates. Though P. annua is commonly considered a solely annual plant due to its name, perennial bio-types do exist. 'Poa' is Greek for fodder. It is one of the sweetest grasses for green fodder, but less ...
  
  )
• Knotgrass (Polygonum aviculare
  Polygonum aviculare
  Polygonum aviculare or Common Knotgrass is a plant related to buckwheat and dock. It is also called birdweed, pigweed and lowgrass. It is an annual found in fields and wasteland, with white flowers from June to October....
  
  )

There are no rare species associated with the community.

Distribution

This ephemeral community is widely distributed throughout the lowlands and upland fringes of Britain. It occurs on loamy and sandy soils that are subjected to disturbance and moderate trampling, such as around tracks and gateways on agricultural land, on wasteland, and in recreational areas. Where trampling is heavier, it is replaced by the Poa annua - Plantago major community, OV21

British NVC community OV21

British NVC community OV21 is one of the open habitat communities in the British National Vegetation Classification system...

.

Subcommunities

There are two subcommunities:

• the Sisymbrium officinale - Polygonum arenastrum subcommunity
• the Plantago major subcommunity