This rhizomatous perennial herb grows in base-rich, mesotrophic and eutrophic water, often occurring in extensive stands. Its habitats include river banks, lakes and pond margins, marshy areas near streams, fen-meadows and tall-herb fen, and carr; it is notably shade-tolerant. It avoids sites subject to marked fluctuations in water level. Reproduction by seed is poor. 0-370 m (near Garrigill, Cumberland).
C. acutiformis was mapped as `all records` in the 1962 Atlas. Apart from some local declines, its distribution seems generally stable.
Eurosiberian Temperate element.
Light (Ellenberg): 7
Moisture (Ellenberg): 9
Reaction (Ellenberg): 7
Nitrogen (Ellenberg): 6
Salt Tolerance (Ellenberg): 0
January Mean Temperature (Celsius): 3.5
July Mean Temperature (Celsius): 15.3
Annual Precipitation (mm): 889
Height (cm): 150
Perennation - primary
Life Form - primary
Life Form - secondary
Clonality - primary
Count of 10km squares in Great Britain: 1501
Count of 10km squares in Ireland: 195
Count of 10km squares in the Channel Isles: 1
Atlas Change Index: 0.16
Weighted Changed Factor: -2
Weighted Change Factor Confidence (90%)
Atlas text references
1988. Comparative Plant Ecology.
1986. Atlas of north European vascular plants north of the Tropic of Cancer. 3 vols.
1982. Sedges of the British Isles. Botanical Society of the British Isles Handbook no. 1, edn 2.
1965. Vergleichende Chorologie der zentraleuropäischen Flora. Volume 1. 2 vols.
1997. Aquatic plants in Britain and Ireland.