Marram Grass, the Weaver of Dunes


In this blog post, Samuel walks us through the role marram grass plays in coastal ecosystems and highlights efforts to protect and restore this important plant. You’ll also find actionable tips on how to share space with marram grass during your next trip to the beach. Let’s tread carefully into the story of marram grass—the unsung hero holding our dunes together.
By Samuel LeGresley, Communications coordinator
I learned at a young age that dunes in New Brunswick are held together by a very special grass called marram grass (Recently reclassified from Ammophila breviligulata to Calamagrostis breviligulata). In the mid-2000s, I was in the Young Naturalists Club (former name of the Nature NB program now called NatureKids NB). Club meetings were held at the Bouctouche Dune pavilions, where marram grass is essential to the structure of this famous sand spit. In fact, the boardwalk at the Irving Eco-Centre was built – and rebuilt several times to prevent walkers from stepping on the grasses and damaging the fine structure of rhizomes, or underground stems. Rhizomes link the plants, creating a weather-resistant “web” or “carpet” that holds sand in place. Despite its importance to dune structure, marram grass is a very fragile grass. Foot and vehicle traffic damage the plants, creating physical breaches in the dunes where plants no longer grow – a relatively common sight today.
As I grew older, I always noticed this grass along the coast. When I was studying geography at university, I was fortunate to learn even more about how marram grass plays an important role at a regional scale, by anchoring dunes through the combined force of longshore drift (the movement of sand along the coast) and the accumulation of sand on the underground network of rhizomes. From this time on, I always thought of dunes as a moving, dynamic ecosystem.


In 2022, working with Vision H2O, I helped develop a campaign focused on the Fs of a dune system: flora, fauna, and function. The function is fairly obvious. Dunes create a barrier between land and sea; a habitat and a food source for fauna. Our iconic Piping Plover is one example of this, as well other shorebirds and insects. In addition to marram grass, sea lymegrass (Leymus mollis), seaside Goldenrod (Solidago sempervirens) and beach pea (Lathyrus japonicus) thrive on healthy dunes. These plants not only provide food and habitat, but work together to literally weave the dune together.

Working under the Healthy Coasts project
Fast forward a few years, and through my work with Nature NB I have had another opportunity to engage with this unique plant. Nature NB’s Wele’k Pemjajika’q Siknikt – Côtes en santé N.-B. – Healthy Coasts NB project works to engage communities in species at-risk conservation projects along the eastern New Brunswick coast.
Marram grass is central to the coastlines this project aims to support, and thanks to partners like the Nature Conservancy of Canada, Ghost Gear Disappear, and community members of Miscou Island – initiatives are now underway to plant marram grass at key locations to restore dunes. Check out the video below highlighting a recent workshop on Miscou.
Planting Marram Grass from seed
While plants and seed can be hard to come by, Vision H2O and other environmental groups are developing expertise to grow marram grass in our region.
For several years, Vision H2O grows the grass from seed, to help nurture dune restoration efforts. Although the transplants are stronger in the short term than these seedlings, this effort makes it possible to achieve the real volume of production that dune restoration requires.
This month, I had the chance to see Vision H2O’s newly-developed seed cleaning, or threshing, process in action. Using a “wind tunnel”, a vacuum sorts the seeds from the small husks. The final product is the small, beige seed at the end of the following video.
The importance of education
Marram grass is the carpet that weaves the dune together, creating a whole ecosystem that supports wildlife and protects communities from extreme weather.
Despite the gains we’ve made in recent years, there’s still a long way to go. You can spread the word about the importance of dune grasses when it’s time to go to the beach.
To protect our dunes, please follow these tips the next time you visit the coast:
- keep motorized vehicles off the dunes and sand spits
- avoid making paths through grasses
- use bridges and boardwalks, where available
- pick up litter found on beaches
For more information on Healthy Coasts, visit coasts.naturenb.ca
