Ammophila arenaria is a species of grass known by the common names European marram grass and European beachgrass. It is one of two species of the genus Ammophila (marram grass). 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 outward. These rhizomes can grow laterally by 2 metres (7 feet) 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 thick and coated in a white waxy cuticle. They are up to 1 metre (3.3 ft) 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.
Invasiveness: Pacific coast of North America
A. arenaria is also recognised as one of the most problematic noxious weeds of coastal California. This sand-adapted grass was introduced to the beaches of western North America during the mid-nineteenth century to provide stabilization to shifting sand dunes. It grew readily and it can now be found from California to British Columbia. 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 alexandrinus). The plant's spread has changed the topography of some California beach ecosystems, especially in sand dunes. The presence of this grass was a major cause of the destruction of native dune habitat in Oregon and Washington during the twentieth century.
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. Studies to find the best methods are ongoing.
- Apteker, Rachel. "Invasive Plants of California's Wildland: Ammophila arenaria". California Invasive Plants Council. http://www.cal-ipc.org/ip/management/ipcw/pages/detailreport.cfm@usernumber=5&surveynumber=182.php. Retrieved 2008-09-18.
- "UC Cooperative Extension Species Profile: Ammophila arenaria". University of California. http://ucce.ucdavis.edu/datastore/detailreport.cfm?usernumber=5&surveynumber=182. Retrieved 2008-09-18.
- Pickart, Andrea J. (1997). "Control of European Beachgrass (Ammophila arenaria) on the West Coast of the United States". 1997 Symposium of the California Exotic Pest Plant Council. http://www.cal-ipc.org/symposia/archive/pdf/1997_symposium_proceedings1934.pdf. Retrieved 2008-09-20.