Have you ever stood on a rooftop in New York City and gazed out at the cement forest of skyscrapers sprouting up from every direction? What you may not realize is that outside the large green rectangle of Central Park, there are other small patches of green breathing life into the city. In my first experience on a living roof, I found myself at a hidden sanctuary for rare New York plants, creatively integrated into the façade and rooftop of a residential building.
This is one of two sites in New York City growing a rare, threatened plant from central New York in an otherwise unlikely environment. Due to its specific habitat requirements, the American hart’s- tongue fern would not fit in among the forest of skyscrapers if not for the efforts of several partners including the State University of New York College of Environmental Science and Forestry (SUNY-ESF), the Brooklyn Botanic Garden, Local Office Landscape and Urban Design and Michael K Chen Architecture.
Young American hart’s-tongue fern from SUNY-ESF, Photo: Justin Dalaba, USFWS
This evergreen, perennial fern has caught the interest of biologists, including Don Leopold and Danilo Fernando at SUNY-ESF, for nearly a century, due to its unique tropical appearance and rarity. Listed as a threatened species under the Endangered Species Act, the fern occurs across only a narrow band of habitat extending from New York to northern Michigan, and in two very small populations found within limestone sinkholes in the South. Recently, SUNY-ESF has partnered with our New York Field Office to obtain funding from the Great Lakes Restoration Initiative for genetic studies and efforts to boost populations by producing plants in the university’s lab. SUNY-ESF has expanded these conservation efforts by donating some lab-produced plants from Central New York to a couple of new homes in New York City.
One of the new homes for American hart’s-tongue fern at the Brooklyn Botanic Garden. Photo: Justin Dalaba, USFWS.
So how might a few plants in a big city have an impact? I spoke with Uli Lorimer, a curator of native flora at the Brooklyn Botanic Garden, which is one of two sites harboring this fern in New York City, and he said:
“There really aren’t many places where the public can come and have a personal and intimate experience with a rare plant and especially one that is very much a New York plant.”
Uli Lorimer at the Brooklyn Botanic Garden. Photo: Justin Dalaba, USFWS.
Uli explains, “I think having plants that people can actually see and then combine that with good interpretation to tell people about the story of the plant are really powerful ways to get people to have some kind of value for not just the plant itself, but the hope is that they extend that same set of values to protecting habitat and wild places.” With a little under a million worldwide visitors coming to the Brooklyn Botanic Garden every year, there seems to be an opportunity for many people to be exposed to this plant as a small example of a greater effort for the conservation of endangered species.
Interpretive signage in the native flora garden describing the sensitive habitat of hart’s-tongue fern. Photo: Justin Dalaba, USFWS.
After touring the Brooklyn Botanic Garden, I was able to visit the second new home for these Central New York ferns. Local Office Landscape and Urban Design has come up with a unique designed experiment, now three years in the making, which features a variety of rare, native plants integrated into the wall and rooftop of a recently renovated residential building.
Five-story high residential building featuring the Greenwall in Manhattan. Photo: Justin Dalaba, USFWS.
The Greenwall Project in Manhattan brings three upstate New York climates to the heart of the city, from the “cliff bottom” or “cave dwellers,” to the “cliff face” and reaching high to the “cliff top” of this five-story building. “Some of the habitats or microclimates, if you will, on this building are very close to a lot of the habitats that we find just outside the city or further upstate” says Walter Meyer, an urban designer for Local Office Landscape and Urban Design and professor at Parson’s New School. These plants require very specific conditions, such as levels of moisture, wind and light, meaning this project was not as simple as putting soil in pots on a wall.
Meyer describes the Greenwall project as the “perfect canvas” for conservation with the American hart’s-tongue fern as a “poster child.” Meyer explains,“It is the Canary in the Coal Mine for climate change, meaning it’s one of the most exposed species in New York State to climate change.” With the threat of warming temperatures everywhere, there are increasingly fewer places for such a sensitive species with specific habitat requirements to thrive.
Walter Meyer on the roof of the Greenwall site, where a variety of “cliff top” plants are being grown. Photo: Justin Dalaba, USFWS.
“Typically in science, biology, conservation, a lot of [experiments] are done in labs and the publications are for small circles to be peer-reviewed, but I think there are opportunities where certain lab experiments should start to influence public policy. And when you start to influence the mainstream and public policy, you get more funding opportunities, so it’s a self-feeding loop of funding science in response to climate change and loss of biodiversity,” says Meyer.
American hart’s-tongue fern, strategically placed near the bottom of the Greenwall. Photo: Justin Dalaba, USFWS.
“It’s sort of the perfect species,” says Meyer of the American hart’s tongue fern. He explains that If we had writers, artists, journalists, regulators, policy makers, and decision makers all exposed to such a beautiful plant that is so important to New York State’s biodiversity, it can have an impact on many levels, culturally and ecologically. With the plant and information available at the Brooklyn Botanic Gardens, many city-dwellers and visitors have the opportunity to relate more closely to an important conservation issue through this iconic plant.