Triglochin maritimum

Sea arrowgrass
Scientific classification
Kingdom:	Plantae
(unranked):	Angiosperms
(unranked):	Monocots
Order:	Alismatales
Family:	Juncaginaceae
Genus:	Triglochin
Species:	T. maritima
Binomial name
Triglochin maritima L.

Triglochin maritima is a species of flowering plant in the arrowgrass family Juncaginaceae. It is found in brackish marshes, freshwater marshes, wet sandy beaches, fens, damp grassland and bogs. It has a circumboreal distribution, occurring throughout the northern Northern Hemisphere. In the British Isles it is common on the coast, but very rare inland.

It is like marsh arrowgrass (Triglochin palustris) but has the following differences: it has stolons, is stouter. The leaves are fleshy and not furrowed above. It is not very aromatic. The raceme are more dense and like sea plantain. The flowers are fleshier. The fruits are oval, 4 mm long, 2 mm wide.

It varies in height from 8-30 inches (to 45 cm). It flowers in May to August; flowers are greenish, 3 petalled, edged with purple, 1/8 inch (2mm) across, in a long spike. Common names include seaside arrowgrass,common arrowgrass, sea arrowgrass and shore arrowgrass.

It can be an annual or perennial.

Triglochin concinna is a synonym of this species.

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Wikipedia