Scilla autumnalis

Tracheophyta MagnoliopsidaLiliaceaeScillaScilla autumnalis

Ecology

A bulbous perennial herb of open, drought-prone grasslands and heathy vegetation in rocky or sandy places near the sea; also on terrace gravels in the lower Thames valley. Lowland.

Status

Native

World Distribution

Mediterranean-Atlantic element.

Broad Habitats

Light (Ellenberg): 9

Moisture (Ellenberg): 3

Reaction (Ellenberg): 6

Nitrogen (Ellenberg): 1

0

Salt Tolerance (Ellenberg): 0

January Mean Temperature (Celsius): 5.9

July Mean Temperature (Celsius): 16.2

Annual Precipitation (mm): 939

Life form information

Height (cm): 20

Perennation - primary

Perennial

Life Form - primary

Bulbous geophyte

Woodiness

Herbaceous

Clonality - primary

Tuberous or bulbous, slowing cloning by offsets

Comment on Clonality

Check

Count of 10km squares in Great Britain: 49

Count of 10km squares in Ireland: 0

Count of 10km squares in the Channel Isles: 14

Atlas Change Index: -0.37

Distribution information

JNCC Designations

NBNSYS0000002183

Scarce Atlas Account

Scarce Atlas Account: 

Scilla autumnalis L. Status: scarce  

Autumn squill

Status: scarce

 

S. autumnalis grows on terrace gravels by the Thames, dune sands on the Isle of Wight, and Carboniferous and Devonian limestones, schists, serpentine and greenstone in south-west England. It survives near the Thames in acidic grass-heath on golf courses where the dominants include Agrostis capillaris, A. vinealis, Calluna vulgaris and Festuca ovina. The Devonian limestones support Bupleurum baldense and Helianthemum apenninum as well as abundant S. autumnalis. At the Lizard Peninsula its open habitats support numerous associates including Herniaria ciliolata and Minuartia verna. In the Channel Islands it is abundant on gneiss with other geophytes such as Ophioglossum lusitanicum and Romulea columnae and therophytes including Poa infirma. It is confined to the lowlands. 

The bulbs of S. autumnalis tolerate long dry periods but promptly resume growth when moistened. Flowering in late summer precedes the appearance of the overwintering leaves. Bulbs are long-lived; seed is freely produced and may be scattered from the capsules of the persistent infructescences up to 40 cm. Germination usually takes place in autumn.

Some of its Thames valley sites (e.g. Chelsea) have been built over, and it has greatly decreased in the Avon Gorge at Bristol since the 18th century, but it remains locally very abundant on, or near, the coasts of Devon, Cornwall and the Channel Islands, especially where periodic droughts on the shallow skeletal soils reduce competition from more aggressive but more mesophytic species such as Prunus spinosa and Ulex europaeus, or introduced species such as Quercus ilex. Only on deeper soils (often with Scilla verna) are grazing, mowing or burning necessary to prevent succession to heath or scrub.

A species of southern and western Europe, extending along the Atlantic coast to Britain. It is also found in north-west Africa and Asia east to Iran.

Two cytological races occur in Britain: a tetraploid from E. Cornwall eastwards, and also in Jersey, and a hexaploid in the south of Cornwall and in Guernsey (Ainsworth, Parker & Horton 1983, J.S. Parker and L.C. Frost in litt.).

 

C. Chatters & D. E. Coombe

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 (316b)
Stewart A, Pearman DA, Preston CD
1994.  Scarce plants in Britain.