Glyceria fluitans

Water Mannagrass
Scientific classification
Kingdom:	Plantae
(unranked):	Angiosperms
(unranked):	Monocots
(unranked):	Commelinids
Order:	Poales
Family:	Poaceae
Subfamily:	Pooideae
Genus:	Glyceria
Species:	G. fluitans
Binomial name
Glyceria fluitans (L.) R.Br.

Glyceria fluitans (syns Festuca fluitans, Poa fluitans, Panicularia fluitans), known as Floating Sweet-grass and water mannagrass, is a species of perennial grass in the genus Glyceria native to Europe, the Mediterranean region and Western Asia and occurring in wet areas such as ditches, riverbanks and ponds.

It has a creeping rootstock, a thick stem which rises to one metre. The leaves are long, narrow and pale green, rough on both sides, often folded at the keel which lies on the surface of the water.

The species epithet fluitans is Latin for floating.

Glyceria fluitans is a component of Purple moor grass and rush pastures, a type of Biodiversity Action Plan habitat in the UK. This habitat occurs on poorly drained neutral and acidic soils of the lowlands and upland fringe. It is found in the South West of England, especially in Devon.

Glyceria fluitans (1)
Illustration in:
Jakob Sturm: "Deutschlands Flora in Abbildungen",
Stuttgart (1796)

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Wikipedia