Sesleria caerulea

Tracheophyta MagnoliopsidaPoaceaeSesleriaSesleria caerulea

Ecology

A tufted, rhizomatous perennial of well-drained, mainly open habitats on limestone, including grassland and heath, screes and cliffs, and the grikes and clint-hollows of limestone pavement. It extends locally into open woodland in Ireland and N. England, and is found on sandy loams over micaceous schists in Perthshire. 0-1005 m (Ben Lawers, Mid Perth).

Status

Native

World Distribution

European Boreo-temperate element.

© Shannon, P

Broad Habitats

Light (Ellenberg): 7

Moisture (Ellenberg): 6

Reaction (Ellenberg): 8

Nitrogen (Ellenberg): 2

0

Salt Tolerance (Ellenberg): 0

January Mean Temperature (Celsius): 3.1

July Mean Temperature (Celsius): 13.9

Annual Precipitation (mm): 1262

Life form information

Height (cm): 45

Perennation - primary

Perennial

Life Form - primary

Hemicryptophyte

Woodiness

Herbaceous

Clonality - primary

Tussock-forming graminoid, may slowly spread

Count of 10km squares in Great Britain: 76

Count of 10km squares in Ireland: 89

Count of 10km squares in the Channel Isles: 0

Atlas Change Index: -0.09

Distribution information

JNCC Designations

NBNSYS0000002570

Scarce Atlas Account

Scarce Atlas Account: 

Sesleria caerulea (L.) Ard.

Blue moor-grass

Status: scarce

 

This is a characteristic and often dominant grass of the sheep-grazed Carboniferous limestone of northern England. In the Pennines it grows on shallow well-drained rendzina soils. Although such sites may be subject to summer drought, this has little effect on the competitive ability and vigour of S. caerulea. It characteristically occurs in open communities in scree, in crevices and on ledges of scars, extending back from the edge of the scars on to the usually non-calcareous, overlying drift. Although it can tolerate a pH as low as 5, with increasing depth of drift it becomes patchy and eventually disappears. It is also able to grow under the light shade of limestone ash woodland. The open communities are species-rich with, at the upland sites, such characteristically montane species as Draba incana, Galium boreale, G. sterneri, Minuartia verna and Persicaria vivipara, while lowland sites have more southern, thermophilous species such as Asperula cynanchica, Centaurea scabiosa and Hippocrepis comosa. Occurring throughout the altitudinal range are Helianthemum nummularium, Scabiosa columbaria and Thymus polytrichus. There is a small, recently discovered, relict population in the Peak District. It also occurs in a limited area of east Durham on the drier Permian limestone and locally in the Breadalbanes on strongly calcareous mica schist rocks, where it occurs up to 980 metres and is associated with Dryas octopetala, Saxifraga oppositifolia, Silene acaulis and dwarf willows. 

The flowers appear early, often in March, and the culms elongate considerably after flowering, becoming very conspicuous. They may be grazed by both rabbits and sheep. Fruit production, viability and germination are good.

This species is widespread over large areas in northern England and is not under threat.

S. caerulea is a European endemic, occurring chiefly in the mountains of central Europe from the Pyrenees to the Carpathians. There are isolated records from southern Iceland, southern Spain and Albania. It also occurs in western Ireland, where it grows on limestone and coastal sands, and from northern France to central Germany.

For a detailed account of the ecology of this species, see Dixon (1982).

 

G. Halliday

PLANTATT - Attributes of British and Irish plants. (.zip 1455KB) This dataset was compiled and published in 2004, and last updated in November 2008. Download includes an Excel spreadsheet of the attributes, and a PDF explaining the background and nomenclature. Note that the PDF version is the booklet as published, whereas the Excel spreadsheet incorporates subsequent corrections. A hardcopy can be purchased from the Centre for Ecology and Hydrology.

Atlas text references

Atlas (384b)
Dixon JM
1982.  Biological Flora of the British Isles. No. 151. Sesleria albicans Kit. ex Schultes. Journal of Ecology. 70:667-684.
Halliday G
1997.  A Flora of Cumbria.
Hultén E, Fries M
1986.  Atlas of north European vascular plants north of the Tropic of Cancer. 3 vols.
Meusel H, Jäger E, Weinert E
1965.  Vergleichende Chorologie der zentraleuropäischen Flora. Volume 1. 2 vols.
Stewart A, Pearman DA, Preston CD
1994.  Scarce plants in Britain.