White water-lily  (Nymphaea alba)

Common and widespread (3).

The white water-lily produces Britain's largest flower (4). This plant roots in the mud at the bottom of the lake (5), the circular floating leaves are dark green on the upper surface, and reddish below (2). The flowers also float; the petals are white, often with a pinkish tinge, and the stamens are bright yellow (2). The seeds, which are produced in large quantities, are smooth and olive-green in colour (2).

The native range of this attractive species is not clear, as it has been widely collected and transplanted (3). It is found throughout most of lowland Britain, but is absent from Orkney (2). Outside of the British Isles, it is found in Europe as far north as Scandinavia, but is absent from Iceland and the Faeroe Islands (2).

You can view distribution information for this species at the National Biodiversity Network Gateway.

Found in a range of aquatic habitats, including ponds, large ditches, mires and the backwaters of rivers (3).

White water-lily flowers are produced between June and September (6); they are visited by bees, flies and beetles, but it seems that they are often self-pollinated(2). There is much variation in the size of both the leaves and the flowers; certain populations in nutrient-poor waters are much smaller than average (2). These differences seem to have some genetic basis, as even when moved to nutrient-rich waters the plants stay small for a number of years (2).

This species is not currently threatened, but is likely to be vulnerable to disturbance by boat traffic as it lacks submerged leaves (3).

Conservation action has not been targeted at this common and widespread species.

There may be further information about this species available via the National Biodiversity Network Gateway.

For more information on British plants and their conservation see Plantlife- the wild plant conservation charity:
http://www.plantlife.org.uk/
Visit the website of the Botanical Society of the British Isles at:
http://www.bsbi.org.uk