GL4C Agrostis capillaris – Potentilla erecta grassland
Vegetation
The constant grasses in this community are Anthoxanthum odoratum, Agrostis capillaris, Festuca rubra and Holcus lanatus, while Cynosurus cristatus and Danthonia decumbens are frequent (mean graminoid height = 17.6 cm, n = 180). Potentilla erecta, Trifolium repens, Plantago lanceolata and Galium saxatile are the main broadleaved herbs, with Succisa pratensis, Prunella vulgaris, Hypochaeris radicata and Cirsium palustre frequent (mean forb height = 10.2 cm, n = 180). The bryophyte layer is fairly well developed and contains Hylocomium splendens, Rhytidiadelphus squarrosus, Scleropodium purum and Thuidium tamariscinum. Some sites have a measure of calcareous influence evidenced by the occurrence of Carex flacca and Lotus corniculatus.
Ecology
The Agrostis capillaris – Potentilla erecta grassland is chiefly a community of the lower uplands (mean altitude = 137 m, n = 180; mean slope = 13.2, n = 180). The soils vary from gleys to drained mineral earths (mean organic content = 25.2%, n = 116) and are infertile, humid and strongly acidic.
Sub-communities
No sub-communities are described.
Similar communities
Community GL4C is intermediate in nature between the higher upland swards of GL4B Nardus stricta – Potentilla erecta grassland and the variable, somewhat semi-improved swards of GL4A Agrostis capillaris – Trifolium repens grassland which is found at slightly lower altitudes. The present community has greater forb diversity than GL4B but a stronger calcifuge component than GL4A
Conservation value
This is a fairly species-rich grassland community (species/4 m2 = 27.6, n = 199). Examples on calcareous substrates may relate to EU HD Annex I priority habitat 6210 Orchid-rich calcareous grassland*. Examples on siliceous substrates (but with some calcareous flushing) may relate to EU HD Annex I priority habitat 6230 Species-rich Nardus upland grassland*.
Management
These swards are managed as rough grazing land (typically for sheep). The main threats to these grasslands include overgrazing, improvement, abandonment (e.g. bracken or heath encroachment) and afforestation.