A perennial herb of wet, peaty areas, tolerating both acidic soils and those flushed by calcareous springs. It is often found on the margins of pools and in swamps, though it can also thrive on the edges of wet woods, among scattered trees or in fen-carr. Generally lowland, but reaching 370 m near Malham Tarn (Mid-W. Yorks.).
C. diandra has been lost as a result of drainage and scrub encroachment from many lowland sites, especially in S. and E. England, during the 20th century. Most losses occurred before 1930, but are still continuing in England. It is now much better recorded in Scotland and N. Ireland.
Circumpolar Boreo-temperate element.
Count of 10km squares in Great Britain: 378
Count of 10km squares in Ireland: 294
Count of 10km squares in the Channel Isles: 0
Atlas Change Index: 0.22
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.