Synonymy

Limestone hill pasture Smith & Rankin 1903; Festucetum ovinae Moss 1911 p.p.; Limestone grassland Tansley 1939 p.p.; Carboniferous Limestone grassland Pigott 1956, Ratcliffe 1977 p.p.; Sugar Limestone grassland Pigott 1956; Limestone Grassland E Sinker 1960; Potentilla fruticosa localities Elkington & Woodell 1963 p.p.; Seslerieto-Festucetum Ratcliffe 1965; ‘Ordinary’ Limestone grassland Ratcliffe 1965; Seslerio-Caricetum pulicariae Shimwell 1968a; Asperulo-Seslerietum typicum, Helianthemum variant Shimwell 1968a; Potentilletum fruticosae Shimwell 1968a p.p.; Agrosto-Festucetum, Sesleria facies Eddy et al. 1969; Dryas octopetala localities Elkington 1971 p.p.; Festuca ovina-Sesleria albicans vegetation Jeffrey & Pigott 1973; Seslerio-Caricetum pulicariae Shim well 1968a emend. Jones 1973; Thymo-Festucetum sesleriosum Evans et al. 1977; Thymo-Agrosto-Festucetum Evans et al. 1977 p.p.; Sesleria albicans grassland Ratcliffe 1977; Dry sugar-limestone grassland Ratcliffe 1978.

Constant species

Briza media, Campanula rotundifolia, Carex flacca, Festuca ovina, Galium sterneri, Helianthemum nummularium, Koeleria macrantha, Linum catharticum, Sesleria albicans, Thymus praecox, Viola riviniana, Ctenidium molluscum.

Rare species

Alchemilla glaucescens, A. minima, Aster linosyris, Carex capillaris, C. ericetorum, Cypripedium calceolus, Draba incana, Dryas octopetala, Galium sterneri, Gentiana verna, Helianthemum canum, Hypochoeris maculata, Kobresia simpliciuscula, Minuartia verna, Myosotis alpestris, Polygala amara, Potentilla crantzii, P. fruticosa, P. tabernaemontani, Primula farinosa, Sesleria albicans, Thalictrum alpinum, Veronica spicata, Viola rupestris, Tortella densa.

Physiognomy

The Sesleria albicans-Galium sterneri grassland can occur as closed or open swards or, in very rocky situations, as on stabilised talus and small rock ledges or over pavement clints, be reduced to fragmentary assemblages, in which one or more of the major species of the community attain local prominence. The vegetation can be short, but a few centimetres high, with an even closecropped appearance when grazed, or be taller and decidedly tussocky. Sesleria albicans is the most frequent grass and, though it can vary in abundance from dominant to sparse, it is frequently conspicuous with its tufts of rather stiff, glaucous leaves, choked below by persistent sheaths. When growing vigorously and ungrazed, plants can attain a considerable size, spreading laterally by long creeping rhizomes. Then the species behaves more like a winter-green chamaephyte, though its slowly-growing leaves are often masked by dead material which can give a brown tinge to the sward in winter (Dixon 1982).