This rhizomatous perennial herb is frequent as a floating-leaved aquatic in still or slowly flowing waters, and more rarely found as plants with submerged phyllodes in more rapid streams and rivers. It has a very wide ecological tolerance, growing in oligotrophic to eutrophic and base-poor to base-rich water over a wide range of substrates. Although it may be found in shallow swamps, or in water over 5 m deep, it is most frequent at moderate depths of 1-2 metres. 0-760 m (below Stob Ban, Westerness).
There is little evidence for any change in the distribution of P. natans since the 1962 Atlas.
Circumpolar Boreo-temperate element.
Light (Ellenberg): 7
Moisture (Ellenberg): 11
Reaction (Ellenberg): 6
Nitrogen (Ellenberg): 4
Salt Tolerance (Ellenberg): 0
January Mean Temperature (Celsius): 3.5
July Mean Temperature (Celsius): 14.5
Annual Precipitation (mm): 1091
Perennation - primary
Life Form - primary
Clonality - primary
Clonality - secondary
Count of 10km squares in Great Britain: 2340
Count of 10km squares in Ireland: 648
Count of 10km squares in the Channel Isles: 6
Weighted Changed Factor: -16
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.
1965. Vergleichende Chorologie der zentraleuropäischen Flora. Volume 1. 2 vols.
1995. Pondweeds of Great Britain and Ireland. Botanical Society of the British Isles Handbook no. 8.
1997. Aquatic plants in Britain and Ireland.