Marram grass
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| Marram Grass | ||||||||||||
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| Missing image Helmgras_kijkduin_februari_2005.JPG European Marram Grass in dunes near The Hague | ||||||||||||
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Ammophila arenaria |
Marram Grass or Beach Grass is a genus of two species of grass growing almost exclusively on coastal sand dunes, where rhizomes on its extensive root system allow it to survive in a very harsh and windswept ecosystem. The genus is native to both coasts of the North Atlantic Ocean.
Marram has adapted to the harsh conditions of the Main Ridge sand dunes by having leaves which can roll into a tube in dry weather to reduce surface area. They are also shiny and aligned to wind direction in order to reduce transpiration rates and minimise salt deposition from sea spray. Its extensive roots system allows it to tap into deep ground water stores below the dunes, and have small rhizomes which produce necessary nitrates for the plants growth support. The root network also assists in the process of stabilizing a dune.
There are two species of marram grass, barely distinguishable from each other:
- Ammophila arenaria - European Marram Grass. Coasts of Europe (north to Iceland) and northwest Africa. Inflorescence to 25 cm long; broad.
- Ammophila breviligulata - American Marram Grass or Beach Grass. Coasts of eastern North America, including the shores of the Great Lakes. Inflorescence to 30 cm long; narrower.
Both species are listed as invasive plants in many additional areas, where they were introduced to help reduce sand dune erosion. Particular problems are noted on the Pacific Ocean coast of North America, from California north to British Columbia.
A natural hybrid, × Ammocalamagrostis baltica, between Ammophila arenaria and Calamagrostis epigeios occurs in parts of northern Europe, mainly from the Baltic Sea west to eastern England.
External links
- Ammophila arenaria on the northwest coast of North America (http://www.ou.edu/cas/botany-micro/ben/ben183.html) Botanical Electronic News 183 (12 February 1998).
Illustration_Ammophila_arenaria0.jpg