Potamogeton obtusifolius
Ecology
A rhizomatous perennial characteristically found in mesotrophic or meso-eutrophic, acidic or neutral standing waters in lakes, ponds and flooded mineral workings, or in canals and the backwaters of rivers. It may, however, occupy a broader habitat range in areas such as N. Ireland where it is especially frequent. It fruits freely, and also reproduces by turions. 0-480 m (Angle Tarn, Patterdale, Westmorland).
Status
Trends
Although P. obtusifolius is better recorded than in the 1962 Atlas, the map suggests that it has declined throughout much of its British range. There is less evidence of decline in Ireland.
World Distribution
Circumpolar Boreo-temperate element, with a disjunct distribution.
There are no images in this gallery.
Broad Habitats
Light (Ellenberg): 7
Moisture (Ellenberg): 12
Reaction (Ellenberg): 6
Nitrogen (Ellenberg): 5
Salt Tolerance (Ellenberg): 0
January Mean Temperature (Celsius): 3.4
July Mean Temperature (Celsius): 14.7
Annual Precipitation (mm): 994
Length: 190
Perennation - primary
Life Form - primary
Woodiness
Clonality - primary
Count of 10km squares in Great Britain: 601
Count of 10km squares in Ireland: 155
Count of 10km squares in the Channel Isles: 0
Atlas Change Index: 0.96
JNCC Designations
Atlas text references
Atlas (308a)
.
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.