Carex diandra

Tracheophyta MagnoliopsidaCyperaceaeCarexCarex diandra


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.).



World Distribution

Circumpolar Boreo-temperate element.

Broad Habitats

Fen, marsh and swamp (not wooded)

Light (Ellenberg): 8

Moisture (Ellenberg): 9

Reaction (Ellenberg): 5

Nitrogen (Ellenberg): 3


Salt Tolerance (Ellenberg): 0

January Mean Temperature (Celsius): 3.6

July Mean Temperature (Celsius): 14.4

Annual Precipitation (mm): 1042

Life form information

Height (cm): 60

Perennation - primary


Life Form - primary




Clonality - primary

Rhizome shortly creeping

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

Distribution information

JNCC Designations


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