This is a perennial species which grows in large, rapidly flowing rivers with a stable substrate. It is usually found in base-rich and meso-eutrophic water. In Ireland, it is confined to a single, now locally highly polluted, river. Lowland.
This is not a well-understood species; in some areas of Britain it may be under-recorded whereas in others it may be reported in error for other taxa. Historically R. penicillatus subsp. pseudofluitans may have been recorded as R. fluitans, whereas now hybrids with R. fluitans as one parent are more likely to be reported as the species.
European Temperate element.
There are no images in this gallery.
Light (Ellenberg): 7
Moisture (Ellenberg): 12
Reaction (Ellenberg): 7
Nitrogen (Ellenberg): 6
Salt Tolerance (Ellenberg): 0
January Mean Temperature (Celsius): 3.3
July Mean Temperature (Celsius): 15.4
Annual Precipitation (mm): 798
Perennation - primary
Life Form - primary
Clonality - primary
Clonality - secondary
Count of 10km squares in Great Britain: 373
Count of 10km squares in Ireland: 3
Count of 10km squares in the Channel Isles: 0
Atlas Change Index: 1.96
Atlas text references
1988. The Irish Red Data Book. 1. Vascular Plants.
1986. Atlas of north European vascular plants north of the Tropic of Cancer. 3 vols.
Jalas & Suominen (1989)
1997. Aquatic plants in Britain and Ireland.