It is a perennial grass forming stiff, hardy clumps of erect stems up to 1.2 metres (3.9 ft) in height.

[4] The rhizomes tolerate submersion in sea water and can break off and float in the currents to establish the grass at new sites.

It is adapted to habitat made up of shifting, accreting sand layers, as well as that composed of stabilised dunes.

This is facilitated by the bulliform cells located at the base of the V-shaped notch which swells and makes the leaf uncurl when filled with water.

It occurs in Australia, Canada, Chile, Falkland Islands (Malvinas) (sub-Antarctic), New Zealand, South Africa and United States (US).

This sand-adapted grass was introduced to the beaches of western North America during the mid-19th century to provide stabilization to shifting sand dunes.

The grass is invasive in the local ecosystems, forming dense monotypic stands that crowd out native vegetation, reduce species diversity of native arthropods, and cover vital open stretches of sand used for nesting by the threatened western snowy plover (Charadrius nivosus).

The presence of this grass was a major cause of the destruction of native dune habitat in Oregon and Washington during the 20th century,[19] where it was planted precisely for its dune-stabilizing effect.

[20] Several methods have been employed in attempts to eradicate the grass in California, including manual pulling, burning, mechanical removal followed by salt water irrigation, and glyphosate application.

[21] The California Conservation Corps also has made major efforts in the removal of the invasive Beachgrass, such as an initiative at Morro Strand State Beach in 2000.

[23] It has been suggested that prior to the removal of this invasive grass from the coasts of New Zealand that surveys be undertaken to establish whether this endemic moth is present in order to assist with the conservation of that species.

[23] Marram grass does not carry any major disease in New Zealand, as only 3 pathogenic fungi (Claviceps purpurea, Uredo sp.