Greater Duckweed - Spirodela polyrhiza
This is an aquatic plant, usually growing in dense colonies, forming a mat on the water surface. Each plant is a smooth, round, flat shiny green disc on top and often purplish underneath. It may measure 4 to 10 mm across and produces several minute roots (at least two, unlike Common Duckweed).
Lemna species
Many roots, large fronds, reddish underside and turns red in autumn, multiple veins
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Mainly found in still water such as ponds.
Spring and summer, dying back in the autumn.
Perennial.
British records are mainly concentrated in central and southern England.
It is near scarce in Leicestershire and Rutland. In the Flora of Leicestershire (Primavesi and Evans 1988) it was found in 7 of the 617 tetrads.
It was on the 2011 VC55 Rare Plant Register (Jeeves, 2011) but does not meet the criteria for the current RPR (Hall and Woodward, 2022) |
Leicestershire & Rutland Map
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UK Map
Species profile
- Common names
- Great Duckweed, Greater Duckweed
- Species group:
- Wildflowers
- Kingdom:
- Plantae
- Order:
- Alismatales
- Family:
- Araceae
- Records on NatureSpot:
- 9
- First record:
- 06/09/2012 (Nicholls, David)
- Last record:
- 27/09/2022 (Nicholls, David)
Total records by month
% of records within its species group
10km squares with records
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