Carex arenaria is commonly known as sand sedge, and there are several other synonyms for this plant as well. Some of the most common synonyms include sand reed, marram grass, sand couch, and beachgrass. These terms all refer to the same plant species, and they are used interchangeably depending on the context. Sand sedge is a perennial grass that grows in dry and open habitats like sand dunes, heaths, and rocky shores. It is an important plant for stabilizing soil and preventing erosion in these fragile ecosystems. Its fibrous root system helps to hold the sand in place, while its leaves provide shelter for small animals and insects.