(Spartina alterniflora)

This grass grows in salt marshes (duh!), in two forms, one tall, and one short. The taller one grows closer to the source of salt water, and spreads by rhizomes. These help to bind the soil and provide a place for ribbed mussels to attach to and be somewhat protected. It has special tissue called aerenchyma, which helps get oxygen to the roots. It is able to survive in high salinity areas because it concentrates solutes in its tissues, which allows it to use osmosis to its advantage. The location of this plant is highly dependent on competition (on the upper boundary) and physical stress (on the lower boundary.)