CG8 - Sesleria Albicans-Scabiosa Columbaria Grassland

Summary

Synonymy

Magnesian Limestone Rough Pasture Heslop-Harrison & Richardson 1953; Seslerio-Helictotrichetum pratensis Shimwell 1968a.

Constant species

Avenulapratensis, Briza media, Carexflacca, Centaurea nigra, Festuca ovina, Galium verum, Helianthemum nummularium, Koeleria macrantha, Linum catharticum, Lotus corniculatus, Pimpinella saxifraga, Plantago lanceolata, Sanguisorba minor, Scabiosa columbaria, Sesleria albicans, Thymus praecox.

Rare species

Epipactis atrorubens, Linum perenne ssp. anglicum, Primula farinosa, Sesleria albicans.

Physiognomy

The Sesleria albicans-Scabiosa columbaria grassland comprises generally closed swards in which S. albicans is usually the most abundant grass, often dominating as vigorous tussocks, especially when the sward is ungrazed. Festuca ovina (occasionally with a little F. rubra, though rarely exceeded by it) and Briza media are constant, but somewhat variable in abundance. Avenula pratensis and Koeleria macrantha are very frequent, too, though usually in small amounts. There is occasionally a little Agrostis capillaris, Cynosurus cristatus and Brachypodium sylvaticum and, in one sub-community in particular, coarser species such as Avenulapubescens, Dactylis glomerata and Arrhenatherum elatius lend a rank appearance to the sward. Bromus erectus and Brachypodium pinnatum occur rarely, here very much towards their northern limits in Britain and the former prominent only on south-facing slopes. Carex flacca is very common and, with F. ovina, often makes up the bulk of the sward among the S. albicans', C. caryophyllea is also frequent, though usually not so abundant.

Although this vegetation has been very intensively sampled in relation to its extent and the amount of variation it shows, such that it appears somewhat oversolidly defined, the richness of the dicotyledonous element is a real feature of the community. As in the Sesleria-Galium grassland, Thymus praecox and Helianthemum nummularium are both constant and each can be locally prominent, and Sanguisorba minor, Plantago lanceolata, Lotus corniculatus, Campanula rotundifolia, Linum catharticum and Euphrasia officinalis agg. (mostly E. nemorosa) are very frequent as usually scattered individuals. Here, however, there is an additional enrichment from a group of species that are especially characteristic of lowland Mesobromion swards. Especially distinctive among these is Scabiosa columbaria but Galium verum, Leontodon hispidus, Anthyllis vulneraria, Plantago media, Primula veris, Viola hirta, Centaurea scabiosa and Gentianella amarella are also very common and, in two of the sub-communities, Centaurea nigra and Pimpinella saxifraga occur at high frequency.