The Conservation Conversation: The Fight of the Century (Phragmites vs. Spartina, Part 2)

In my last post, I described the two most common salt marsh plants in our area - phragmites (the tall common reed) and spartina (the shorter cord grass).

While both are natural parts of the marshland ecosystem, spartina is ecologically more valuable, but it is also much more sensitive to disturbances, such as dumping and "mudwaves" that raise the elevation of the soil above the plant's comfort zone.

Phragmites, by contrast, are quite happy to grow in disturbed areas. Given the preponderance of disturbed, near-shore areas in our developed, modern world, "phrag" has displaced an awful lot of spartina, resulting in a significant loss of biodiversity and biological productivity in our remaining wetlands. 

In this prize fight, most of the rounds have so far gone to phragmites. During the past few decades, however, efforts have been made to balance the odds and help spartina win a few rounds. Two excellent examples of success in this epic battle can be found right in our own backyard along Alley Creek. 

But first, a short civics lesson. Under the federal Clean Water Act, which was passed in 1972, the filling of wetlands can only be done pursuant to a permit issued by the U.S. Army Corps of Engineers.

The Corps got this job because of its long-time role in keeping navigational waterways free from obstructions, and issuing permits for piers, bridges and the like. For more than a century, it has been the Corps' job - at least on paper - to keep people from dumping inappropriate stuff into the water.

Permits for filling wetlands can be issued when a project is important and can only be built on or near water. In the mid 1990s, such a project was the extension of a LaGuardia Airport runway into Flushing Bay for safety reasons.

The airport obviously couldn't be moved and the only place to extend the runway was into the bay. A total of six acres of open water and wetlands were filled for the extension. Under the conditions of its permit, the Port Authority of New York and New Jersey had to "mitigate" for the loss of those six acres. Mitigation can be achieved through creating new wetlands to replace those lost or by restoring damaged wetlands.

In 1997, the Port Authority mitigated the six acres of lost wetlands in Flushing Bay by restoring 13 acres of degraded wetlands in Little Neck Bay. The selected 13-acre site was immediately west of 233rd Street in the Doug-Bay portion of Douglaston and immediately north of the Long Island Rail Road tracks.

The area was dominated almost entirely by phragmites that had taken over when the ground level was elevated by mudwaves from the construction of the Doug-Bay community in the 1960s. 

The restoration project was carried out with great precision. Soil was scraped from the surface to eliminate the phragmites roots and return the ground to a carefully selected elevation more suitable for spartina than for phrag. 

Channels and a tidal basin were created, allowing seawater to reach far into the 13-acre site during each high tide. During this construction work, the Udalls Cove Preservation Committee - with help from Con Edison - installed an osprey nesting platform at the edge of the tidal basin. After grading was complete, tens of thousands of spartina plugs were planted and surrounded by a network of strings to keep the geese from eating the succulent young shoots. 

The restoration of this 13-acre site was entirely successful. This was a marked difference from a similar effort a few years earlier on the south side of Northern Boulevard that mostly failed because it wasn't yet understood how critical it is to select and achieve precise ground elevations. 

Another restoration project that appears to be very successful is the creation of a large tidal basin and spartina marsh south of the LIRR tracks between Alley Creek and the Cross Island Parkway.

This project, completed a couple of years ago, was also carried out under a wetlands permit. It was put into place to mitigate the impact of the city's construction of a sewage abatement project.

Both restoration areas are great places for bird-watching. And they are both beautiful and interesting areas through which to kayak or canoe. They owe their existence to the Clean Water Act of 1972.