A perennial herb, mainly confined to areas within reach of sea water or spray. It is found on muddy or sandy estuarine flats, at the uppermost levels of saltmarshes and the edges of brackish ditches, and on moist coastal rocks and low cliffs. It often grows with C. distans. Lowland.
There has been little change in the distribution of C. extensa since the 1962 Atlas.
European Southern-temperate element.
Light (Ellenberg): 8
Moisture (Ellenberg): 7
Reaction (Ellenberg): 7
Nitrogen (Ellenberg): 5
Salt Tolerance (Ellenberg): 4
January Mean Temperature (Celsius): 4.5
July Mean Temperature (Celsius): 14.5
Annual Precipitation (mm): 1228
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.