A comeback

Stephen Syphax gave an interesting presentation to the Friends of Dyke Marsh on the wetlands restoration work at Anacostia Park, the first and perhaps most successful being 1993’s 32-acre (13 ha) Kenilworth Marsh project. Syphax is Chief of the Resource Management Division for NPS’s National Capital Parks-East.

Early in the previous century, the tidal lagoons along the slow-moving Anacostia River were viewed as a problem to be rectified: the McMillan Plan captioned an image of the area as “malarial flats to be excavated.” So, wetlands that were home to abundant stands of wild rice (Zizania palustris) were displaced and the river straightened by the Army Corps of Engineers to make way for a golf course, landfill, power plant, and parking lots for RFK Stadium.

Restoration work began in 1991 with pilot-project containments, with the objective of identifying the optimal ground elevation (about 2 meters) for encouraging emergent vegetation. Syphax suggests that too much height promotes the growth of Phragmites australis. Hydraulic dredging (to minimize the suspension of potentially toxic sediments) began shortly thereafter—what Syphax called the arrival of “the big yellow machines.” Novel “water tubes” (think of Godzilla’s garden hose stretched across the marsh) were used as a temporary, low-impact means of containment of dredged-up material as it settled and consolidated. Then came planting of about fifteen species of native plants, 350,000 individuals in all, along with the arrival of another dozen volunteer species—including the invasive Purple Loosestrife (Lythrum salicaria). In retrospect, Syphax says it wasn’t necessary to plant as many different species as they did. Once the plants were established, another machine cut tidal guts into the reclaimed wetland.

A happy result of the restoration work was the sighting of Marsh Wren (Cistothorus palustris) in 1996. And the jewel of the rehab is the reappearance of American Lotus (Nelumbo lutea), which opens its pale yellow blooms over the water each July.

While this phase of the restoration work was quite successful, more recent work in the Kingman Lake area has been hampered by resident populations of Canada Goose (Branta canadensis). The geese saunter over from Langston Golf Course and treat the newly-planted veg as a “salad bar,” in Syphax’s apt phrasing.

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