Heather Liljengren, a field taxonomist with the New York City Department of Parks and Recreation, examines the seed pods of the Virginia spiderwort at Oakwood Beach, Staten Island. Liljengren collects seeds from across the region for a seed bank of native plants.
Heather Liljengren, a field taxonomist with the New York City Department of Parks and Recreation, examines the seed pods of the Virginia spiderwort at Oakwood Beach, Staten Island. Liljengren collects seeds from across the region for a seed bank of native plants. Andrea Hsu/NPR
Across the New York region, people are still working to rebuild homes and businesses after the havoc wrought by Hurricane Sandy. But the storm also devastated the dunes and native flora of New York's beaches.
When the city replants grasses on those dunes, it will be able to draw on seeds from precisely the grasses that used to thrive there. That's because of a very special kind of bank: a seed bank run by the Greenbelt Native Plant Center on Staten Island.
Heather Lea Liljengren has been a seed collector and field taxonomist for the New York City Parks Department, which runs the Native Plant Center, for more than five years. She's been on the hunt for new deposits: plant seeds that might ensure the survival of the city's flora.
Traipsing through the swampy wetlands of Staten Island's Oakland Beach, Liljengren crashes through towering phragmites, the common reeds that have invaded the world's wetlands and compete with local grasses. When the grasses get this tall — taller than an adult human — "It's hard to remember where the trail used to be," Liljengren says.
She says she loves being in a swamp and is thrilled to be out in the wilds of New York City, hunting for seeds that are ripe for collecting. "When people walk around, they maybe just see green. But when I walk around I am drawn to every small flowering thing, from the ground all the way up into the trees."
"Well, what a treat," she says, peering at the blooms of the thin-leafed iris, iris prismatica. "[This is] one of the only spots, I believe, in the five boroughs where this species naturally still exists. ... The insects that will come and pollinate these irises love them."
That's why native flora is so important, Liljengren says: If these plants disappear, then so will the insects. In time, the loss of species will snowball.
Seeds are coaxed out of dormancy in the nursery at the Greenbelt Native Plant Center on Staten Island. The center considers its seed bank the "Library of Congress" for the region's native plants.
Seeds are coaxed out of dormancy in the nursery at the Greenbelt Native Plant Center on Staten Island. The center considers its seed bank the "Library of Congress" for the region's native plants. Andrea Hsu/NPR
Just Before Sandy, A Serendipitous Seed Hunt
Liljengren was on a routine mission last October, just a few days before Hurricane Sandy. She was collecting seeds from Ammophila breviligulata — the grasses that helped stabilize the dunes on the beaches at Far Rockaway, Queens.
"It was serendipitous for sure," she says. "I was in awe and in marvel of these beautiful large, rolling dunes across the beach." But when Liljengren returned a few weeks ago, all of the dunes were gone. Now, the seeds Liljengren collected that October day will likely be a part of the city's restoration of those very beaches.
Oakwood Beach, on the eastern edge of Staten Island, was also ravaged by Sandy. Rows of small houses with views of the Lower Bay and the Atlantic beyond were damaged — many beyond repair. Like the dunes of the Rockaways, these Staten Island wetlands are also in harm's away. The seeds Liljengren collects may help preserve them.
Liljengren and colleague Judith Van Bers range over the greater New York metropolitan area — 25 counties in three states — in search of native seeds. They've collected more than 500 species and hope to get to 700. "Every seed is a possible plant," Liljengren says.
Back at the Greenbelt Native Plant Center, Van Bers is separating seed from grass, Carex pensylvanica, recently collected on Sparta Mountain, N.J. It's primitive, tedious work.
"It's very, very labor intensive, this next step, which is bringing the seed in and cleaning it," says Ed Toth, the director of the center. "It's the biblical separating the wheat from the chaff."
A Bulwark Against The Impact Of Climate Change
Toth says the seeds that his center collects, stores, plants in a green house and then farms out to others all comprise a kind of plant-seed savings and loan — one that knows its local needs and environments.
"Populations have adapted to local conditions. Those adaptations are captured in their genes," Toth says. "You want to keep that basis healthy and vital."
Of course, threats like rising waters and temperatures may require further adaptation and new genes. "Many species are highly adaptable," he says. "Some may adapt very well if the temperature rises significantly."
But which species? Toth says scientists simply don't know yet. So the aim of his native plant center is to have a huge backup supply in store, before the city discovers its next need, whether that's seeding a landfill, replacing dune grasses on city beaches or planting trees in parks where old trees have fallen.
He figures the bank will be especially important if calamitous conditions become more common.
"It's a hugely complex story about how this is going to unfold, this man-made change that we're bringing upon the world," Toth says. "What we need is the raw genetic material that's contained in these healthy populations. It's like having a Library of Congress in seed, so that all of this tremendous diversity is available to us when we face these problems in the future."