Saltmarsh Cordgrass is the tall grass of the estuaries, growing at the edges of swift channels and wide bays. I grew up calling it Spartina Alterniflora, but recent advances in genetic testing have revealed it to be part of the Sporobulus family of grasses, and it was reclassified in 2019. Whatever you call it, it is the base of the salt marsh, providing habitat, nutrients, and oxygen to the estuary. These “services” have economic values for people too:
The Saltmarsh inspires reverence
“To stand at the edge of the sea, to sense the ebb and flow of the tides, to feel the breath of a mist moving over a great salt marsh, to watch the flight of shore birds that have swept up and down the surf lines of the continents for untold thousands of years, to see the running of the old eels and the young shad to the sea, is to have knowledge of things that are as nearly eternal as any earthly life can be.”
Rachel Carson
What Saltmarsh Cordgrass does for us:
Adaptations
Smooth cordgrass has some amazing adaptations that allow it to live and thrive in quickly moving salt water. They actually have glands that allow the grass to excrete salt, and they have networked roots which hold together and stabilize the grass during high tides and high wave energy. This allows the grasses to serve as a sort of energy sponge when storms are headed to the mainland, absorbing and mitigating that energy before the storm reaches the shore.
Reproduction
This grass has THREE different ways to reproduce. How cool is that?!?
- The roots are an incredibly networked crowd of rhizomes that hold the grasses together but also allow it to spread underground.
- Occasionally, a mat of these breaks off and travels via high tide to another spot, where it can take root in the forever shifting substrate of the maritime environment.
- By flowering. Our grass is blooming right now:
Food
Basically, the saltmarsh cordgrass provides and anchors the entire food chain: it photosynthesizes sunlight into nutrients that can be absorbed. When the grasses eventually break and decay, micro-organisms help decompose it into tiny particles known a detritus. Lots of animals feed on that detritus, including the fiddler crabs in this post. As we move up the food chain, we get to organisms that we like to eat, like shrimp, oysters, and blue crabs. These also support the local commercial fishermen.
Habitat
The Southeast has over 1 million acres of salt-marsh/tidal creek habitat which provide places for young fish, crabs, and even mammals to grow. Birds also use the salt marsh for feeding and nesting.
Climate Resilience
According to SCDNR in its publication, Guide to the Saltmarshes and Tidal Creeks of the Southeastern United States,
Another benefit of the salt marsh-tital creek ecosystem is the reduction of carbon dioxide (a greenhouse gas). Plants take up carbon dioxide from the atmosphere during photosynthesis, converting the carbon into living and dead plant material. Along the coastline, this is termed, “blue carbon”, referring to the carbon captured by coastal plants such as mangroves, sea grasses, and salt marsh grasses and then stored in coastal ecosystems. These coastal plants are reported to sequester 100 times more carbon than forest plants.
In addition to the carbon sequestration, the saltmarsh provides a virtual barrier for the mainland, absorbing wind and wave energy and protecting it from storms and predictable king tide events, as you can see from the pair of photos below.
