Smooth Cord Grass (Spartina alterniflora)

Spartina grass, a smooth cord grass, is a grass that grows in saltwater. It is the most common grass in tidal marshes on Georgia's coast. It grows in very large patches, sometimes covering several kilometers (miles) of area. Spartina grass is adapted to live in the difficult environment of a tidal marsh. It can tolerate changes in salinity and water depth as the tides flow in and out of the marsh.

Spartina grass plays an important role in the estuary food web. The grass provides food directly and indirectly to many animals. Insects such as grasshoppers eat the grass, and spiders prey on insects eating the grass. Algae and detritus floating in the water stick to the grass stems. Small animals such as snails cling to the grass and graze on the algae and detritus. Surprisingly, Spartina grass provides the greatest amount of food when it is dead. When Spartina grass dies, it may become a large floating mass of dead grass, called a wrack (see picture). Bacteria and other microorganisms break down the dead grass into pieces of detritus. It takes about a year for the grass to be broken down into pieces of detritus small enough to be eaten by other animals. Clams, oysters, mussels, snails, crabs, and many other animals feed on this detritus.

Spartina grass also provides habitat for many animals. The dense stems provide cover for fish and crabs hiding from predators. Mussels grow in clumps at the base of the stems.