Ammophila arenaria

Ammophila arenaria is a species of grass in the family Poaceae. It is known by the common names marram grass and European beachgrass. It is one of two species of the genus Ammophila. It is native to the coastlines of Europe and North Africa where it grows in the sands of beach dunes. It is a perennial grass forming stiff, hardy clumps of erect stems up to 1.2 metres (3.9 ft) in height. It grows from a network of thick rhizomes which give it a sturdy anchor in its sand substrate and allow it to spread upward as sand accumulates. These rhizomes can grow laterally by 2 metres (6 ft 7 in) in six months. One clump can produce 100 new shoots annually.

The rhizomes tolerate submersion in sea water and can break off and float in the currents to establish the grass at new sites. The leaves are up to 1 metre (3 ft 3 in) long and sharply pointed. The cylindrical inflorescence is up to 30 centimetres (12 in) long. It is adapted to habitat made up of shifting, accreting sand layers, as well as that composed of stabilised dunes.