by Alexa Livingston, Rachel Carson NWR Intern

Stretching 50 miles along the southern Maine coast, Rachel Carson National Wildlife Refuge preserves and protects delicate salt marsh ecosystems and the rich history of coastal New England agriculture preserved within them. On any given summer morning, Refuge staff head out to one of the 13 estuaries encompassed by the Refuge to collect data, restore habitat, and discover remnant agricultural structures designed by salt marsh farmers that tell a fascinating story.

In the 1800s, entire coastal New England families were headed to the salt marsh by 3 am. Salt hay (Spartina patens) was easiest to cut while it was still wet with morning dew. With them they carried hay rakes, scythes, and switchel – a drink made with oat cakes, cider, lemon, and sugar (and usually rum), that would ferment over winter and was believed to keep the mosquitoes and green head flies at bay.

Each family member had a role in the harvest. The men would carry the scythes, long poles with handles and curved blades at the end and would spread 6-8 feet apart. In unison, the men would step, count, and swing as they made their way across the salt hay meadows. Women and children would follow behind with hay rakes, sometimes many feet in width, and pull together haystacks that would later be piled high onto a configuration of wooden posts, called staddles, to dry (Figure 1). The staddles were elevated to allow the high tides to flow underneath the drying hay throughout autumn and winter. When the harvest was complete, farmers employed two strategies for collecting their hay. They could bring in a team of horses and wagon to gather the hay when the marsh was frozen. If there was a sufficiently wide creek nearby, they could instead pitch the dried hay onto a gundalow that had been floated in at high tide to transport it back to their farm.  

Figure 1. Farmers stacking salt hay. (Accessed in Oliver, 2022).

The 1800s were the peak for salt hay farming – the marsh became the backbone of the early New England coastal farming communities. Salt hay was higher in nutrients than other hay, and the added benefit of the salt meant that farmers didn’t need to purchase additional salt blocks for their cattle. Salt hay proved to be a good insulator for homes and was used to package fragile commodities like bottles. Salt hay had another unique quality – it was the perfect mulch and fertilizer for gardens, because unlike other hays, its seeds need specific conditions, only found in salt marshes, to germinate.

Though there was a high demand for it, salt marsh farming posed significant risks. Both humans and animals risked getting stuck in peat and mudflats or getting caught in unforeseen storm tides. While farmers of other landscapes were quickly advancing their technologies to manage the land, marsh farmers were bound by tradition, and dependent on the strict environmental cycle of the tides.  To make salt marshes “farmer friendly” as well as increase the total yield of hay per acre, dikes and levees were constructed in the early 1800s to hold back seawater from entering the marshes and a system of ditches and wooden water control structures, called trunks (Figure 2), diverted seawater off the marsh surface (Figure 3). Feeder ditches were used to drain smaller areas of the marsh and were connected to the primary trunks in a grid-like fashion (Figure 4). These efforts made the land more arable, easier to harvest, and safer for the farmers to bring their animals and families across because the ground was drier and more stable.

Figure 2. Remnants of a wooden trunk in a tidal channel at Rachel Carson NWR. (Susan Adamowicz/USFWS).

Figure 3. This widely distributed diagram from 1820 illustrates how farmers were encouraged to alter salt marshes. (Chotanter, 1820).

Unfortunately, farmers could not foresee the unintended consequences their reclamation efforts would have on the ecosystem. Dikes and ditches, once considered “modest” alterations, disrupted the natural hydrology and salinity of the marsh, impacting the plants and wildlife dependent on regular tidal fluctuations. Over time, stagnant pools of water became breeding grounds for mosquitoes and by the late 19^th century, salt marsh farming was losing its value. Salt marshes which were once viewed as the “ocean’s perfect nursery,” became regarded as disease-ridden and dangerous and were drained for development to support the booming coastal tourism industry.

Figure 4. Aerial imagery showing ditches and embankments across a salt marsh at Rachel Carson NWR.

In recent years, marsh restoration professionals have realized the impact agricultural alterations have had on natural elevation-building processes. Vertical accretion is a process that enables marshes to keep pace with sea-level rise by sequestering minerogenic sediment and building organic sediment. Ditches dug by farmers centuries before were not maintained post-farming and embankments continued to block surface sheet flow. As sediment built up and blocked tidal flow in ditches, the marsh surface was unable to drain sufficiently at low tide. As soil saturation increased, plant die-off followed, reinforcing a cycle of mega-pool formation and expansion (Figure 5).

Figure 5. Embankment and surrounding mega-pool at Rachel Carson NWR. (USFWS).

Using these new insights, the LMRD (Land Management Research and Demonstration) Program at Rachel Carson NWR and their partners are developing strategies to reverse the damage and increase marsh resiliency, which ultimately preserves the cultural history associated with them. Their enthusiasm for the work lies in their newfound understanding of the marshes’ ecological response to the farming alterations and to incorporate them into restoration design. To learn more about restoration efforts, visit https://www.fws.gov/project/land-management-research-and-demonstration-areas.

References

Adamowicz, S. C., Wilson, G., Burdick, D. M., Ferguson, W., & Hopping, R. (2020). Farmers in the Marsh: Lessons from History and Case Studies for the Future. Wetland Science and Practice, 37(3), 183–195. https://doi.org/10.1672/ucrt083-224.

Chotanter, A. (1820, October). The Draining of Marshes. American Farmer, Vol 2, 243–245. https://ia801602.us.archive.org/32/items/americanfarmer2021balt/americanfarmer2021balt.pdf.

McKown, J. G., Burdick, D. M., Moore, G. E., Peter, C. R., Payne, A. R., & Gibson, J. L. (2023). Runnels Reverse Mega-Pool Expansion and Improve Marsh Resiliency in the Great Marsh, Massachusetts (USA). Wetlands, 43(35). https://doi.org/10.1007/s13157-023-01683-6.

Oliver, D. (2022, December 18). Cape Cod Salt Marshes – Asset or Swamp? Historical Society of Old Yarmouth. https://www.hsoy.org/blog/2022/12/13/the-cape-cod-salt-marsh.

Sebold, K. R. (1998). The low green prairies of the sea: Economic usage and cultural construction of the Gulf of Maine salt marshes (Publication No. 9913406) [Doctoral dissertation, The University of Maine]. ProQuest. https://www.proquest.com/openview/9835004fa43afb0125e96d3c108213ba/1?pq-origsite=gscholar&cbl=18750&diss=y.

Silveira, J. (Ed.) [hamptonhistoricalsociety8645]. (2012). Salt Marsh Farming on the New Hampshire Seacoast [Video]. YouTube. www.youtube.com/watch?v=TEG_-8RlDp0.

Smith, D. C., Konrad, V., Koulouris, H., Hawes, E., & Borns Jr., H. W. (1989). Salt Marshes as a Factor in the Agriculture of Northeastern North America. Climate, Agriculture and History, 63(2), 270-294. http://www.jstor.org/stable/3743517.