David B. Caruso, Associated Press Yahoo News 2 Apr 10;
NEW YORK – Oriental Bittersweet was an exotic foreigner still found mostly in East Asia when the New York Botanical Garden planted its first specimen in 1897.
Today, it is everywhere. The shrubby vine is common in woodlands and fields in 21 states, ranging from North Carolina, to Maine, to Illinois.
The American Bittersweet, meanwhile, has been in a slow decline.
Once common across the eastern two-thirds of the U.S., the native version of the plant still is around, but it has vanished from many areas now dominated by its hardier, faster-breeding Asian cousin.
"We go entire seasons now without seeing it," said Gerry Moore, director of the science department at the Brooklyn Botanic Garden.
The rise and fall of the two plants has been chronicled by the Botanic Garden as part of a 20-year study that offers a dispiriting outlook on the future of some native flora.
So far, the project has identified 50 native species that have disappeared from metropolitan New York during the last 100 years, and others that have become far less abundant due to factors including the destruction of their habitat, pollution and competition from foreign interlopers.
In some areas, the landscape is also becoming less biologically diverse.
"While you used to have a marsh of 50 or 60 species, you might now have an entire marsh of phragmites, the common reed," Moore said.
The study focused on counties within 50 miles of New York City, but experts say other scientists have made similar findings nationwide.
In the West, sagebrush has been giving way to cheatgrass, which found its way to the U.S. in packing materials and ship ballast in the late 1800s.
Nature lovers strolling through wooded glades, thinking they are among trees that have stood since the Revolution, are actually looking at Norway Maple native to Europe.
Kudzu, which hails from Japan and China, infested the South after farmers in the 1930s through the 1950s were encouraged to use it to stop soil erosion.
Even the pristine open spaces of Grand Teton National Park in Wyoming are now populated with Houndstongue and Yellow Toadflax, both from Europe.
Bit by bit, scientists say, the American landscape is becoming less American.
"We are going to our national parks now and seeing Europe," said Tom Stohlgren, a research ecologist for the U.S. Geological Survey. "We are homogenizing the globe at a very fast rate."
Experts say the trend has many causes, but the biggest one may turn out to be globalization.
European traders and settlers have been bringing Old World plants to the Americas since colonization, but the process has accelerated with every advance in travel.
Now, foreign species arrive so frequently aboard planes, trucks and cargo ships that the odds of the next Oriental Bittersweet arriving are exponentially greater.
"That's the scary part, and the $64,000 question," Stohlgren said. "What we have had is an explosion in trade and transportation, and we have yet to see the full effect of that."
"It took 170 million years for the continents to drift apart, but only 400 years to move them all back together," he said. "I describe this as Darwin on steroids, and we are going to see extremely fast changes because of it."
Climate change and pollution may only worsen the problem, as they make the habitat of many native plants less hospitable, said Peter Raven, president of the Missouri Botanical Garden in St. Louis.
"Obviously the loss of wild areas and their reduction in size makes it harder for natives to persist. As global warming proceeds, it will get worse," he said.
The problem is one that has attracted attention both in the U.S. and globally.
The Nature Conservancy, a leading environmental group, has persuaded some major home and garden retailers to stop selling invasive trees like the Norway maple and Lombardy poplar in regions.
It also has been working with researchers and government regulators on developing models that might predict when a nonnative plant might have the potential to become dangerously invasive, if imported into the U.S.
Several states have established advisory committees on invasive species and a few have banned the sale of plants like the Purple Loosestrife and the Japanese barberry, both of which came over the late 1800s and are now out-competing native flora.
The U.S. Coast Guard has been working on draft regulations for ballast water, aimed at preventing ships from picking up invasive aquatic organisms on foreign coasts and bringing them into North American waters.
Any changes will come too late to prevent some of the native losses identified by Brooklyn Botanic Garden researchers.
Their comprehensive and ongoing survey has found that wildflowers such as the Scarlet Indian Paintbrush, pennywort, Sidebells wintergreen and the Sundial lupine have all seriously declined in the region
At the same time, camphor weed, one found only in the South, has become common throughout the metropolitan area.
"There is still a lot of native diversity out there, but this is an alarm," said Troy Weldy, director of ecological management for the Eastern New York chapter of the Nature Conservancy, and co-author of the New York Flora Atlas.
Species shift due to globalization, he said, "could turn out to be much more of a threat than climate change."
After a 20-Year Mapping Effort, Hoping to Save Dozens of Native Plants
Sindya N. Bhanoo, The New York Times 2 Apr 10;
American colonists once watched for the spring bloom of the Nantucket shadbush, a sign that it was warm enough to bury the winter’s dead.
Today, that shadbush and dozens of other flora native to the New York region face extinction, a result of urban development and the encroachment of invasive plants from foreign lands, scientists from the Brooklyn Botanic Garden report.
Hoping to revive the plants, the scientists recently completed a 20-year project mapping species in every county within a 50-mile radius of New York, providing detailed information on the health of more than 15,000 native and nonnative species.
Humans have clearly made their mark. “Plants from other parts of the world are now quite abundant, but there are many others that have been lost due to urbanization,” said Gerry Moore, the botanical garden’s science director.
Dr. Moore said the institution was hoping the maps would inspire city and county officials and local gardeners to begin planting endangered species.
In addition to the Nantucket shadbush, sometimes called the Juneberry for its edible summer-ripening berries, the study found that at least 50 native varieties were in danger of extinction, including the coastal violet, a unique variety of violet with dissected leaves, and the hairy angelica, a small plant with a burst of tiny white flowers.
Because plants are a crucial part of the region’s broader biodiversity, the loss of a native plant could lead to a disappearance of a native insect, bird or other fauna that depend on it for food, Dr. Moore noted.
The introduction of invasive species from Europe and Asia has played a big role in the retreat of some species, including the American bittersweet, a vine valued for its attractive foliage and small inedible orange berries. It was abundant in the region from the 1800s to the early 1900s, according to records. Then the Asian bittersweet, introduced from East Asia in the 1850s, starting taking over.
Gardeners had embraced the Asian variety because it was easier to grow, but it turned invasive, spreading wildly and eliminating other plants.
Other native plants seem to have diminished as housing, roads and other construction carved through meadows, woodlands and sandy shoreland. Historical accounts first describe the coastal violet as a resident bloom on Staten Island in the late 1800s. Today it is found only in coastal areas of Long Island and in Monmouth County, N.J.
But the Brooklyn Botanic Garden has carefully nursed the coastal violet in its native plant garden in the hope of making seeds available for restoration projects. This year, Dr. Moore said, local gardeners might consider planting that flower, whose seeds can be found at public gardens and nurseries, or the American bittersweet instead of other violets or the Asian bittersweet.
Movements have long been under way on the city and county level to revive native plants. The Greenbelt Native Plant Center, a division of New York’s Department of Parks and Recreation, opened 30 years ago and is still planting native species in the city’s parks and gardens.
The Brooklyn Botanic Garden’s unfolding flora survey has been a critical guide to the center over the years, said Greenbelt’s director, Edward Toth.
“We need to know where to find these things, we need to know where they were historically located, and we need some information on the relative health of these plants,” Mr. Toth said.
Over the last two decades, the botanical garden has relied on dozens of individuals and local botanical groups to survey blocks of land in their neighborhoods, counting and identifying plants in open fields, vacant lots and even sidewalk cracks.
Among the volunteers in the late 1990s was Mariellé Anzelone, who was then a graduate student in ecology at Rutgers who planned to devote her career to tropical biodiversity .
Inspired by the flora project, she changed course, and now designs native plant gardens for yards, terraces and roofs in the New York area.
“There’s actually real nature right here — real, bona fide grasslands and wetlands and meadows right here — but less of it, and that makes it even more precious,” said Ms. Anzelone, 39, who grew up in Westfield, N.J. “Working on this project opened my eyes to the nature in my own backyard.”
New York City study: 50 native plants disappearing
posted by Ria Tan at 4/03/2010 03:34:00 PM
labels exotics, global, global-biodiversity, urban-biodiversity