Canadian Waterweed

Canadian Waterweed - Elodea canadensis

Alternative names
Canadian Pondweed
Description

Forming deep green masses at or below the water surface, much branched, the shoots not collapsing out of water. Leaves in whorls, usually of three, the lowermost opposite, tongue shaped, at least 2 mm wide curved and minutely toothed. Flowers white or pale purple 4 to 5 mm, the male borne on long thread like stalks.

Similar Species

Elodea canadensis and Elodea nuttalli are very similar but can be separated by the leaf shape. E. canadensis has more oval leaves whilst E. nuttalli has strap-shaped leaves. Watch this video for a useful guide to both these species.

Identification difficulty

with a detailed image showing the leaf shape

Recording advice

A good image is required showing the leaf details.

Habitat

Lakes, ponds and canals.

When to see it

May to September.

UK Status

Widespread and common in Britain.

VC55 Status

Locally frequent in Leicestershire and Rutland. In the 1979 Flora survey of Leicestershire it was found in 122 of the 617 tetrads.

Leicestershire & Rutland Map

MAP KEY:

Yellow squares = NBN records (all known data)
Coloured circles = NatureSpot records: 2025+ | 2020-2024 | pre-2020

UK Map

Additional images

All NatureSpot records