Boston — TEXAS wild rice, a little-known cousin of the widely eaten wild rice from the cooler climes of the upper Midwest, didn't attract much attention when it began disappearing from the earth. And that's unfortunate, says Donald Falk of the Center for Plant Conservation in Boston.
Texas wild rice can survive hotter and drier weather than its Northern cousin, a property that may be transferable to a number of widely cultivated crops. And human beings haven't yet learned what other secrets the plant may hold - many plants have been found to have important scientific properties, for instance.
That's why botanists sought out the last wild population of the plant and brought back enough seed to begin growing it in a greenhouse. Eventually they hope to have a strong enough ``captive'' population to begin reestablishing the crop in its natural range.
It's a story Mr. Falk, his associates at the center, and the people at 19 botanical gardens and arboretums around the country hope to reproduce many times. About 5,000 times, in fact.
The center, in Boston's Arnold Arboretum, is the heart of a network dedicated to saving the approximately 5,000 endangered plant species found only in the United States.
So far, 221 species from the center's 118-page list of endangered US plants have been taken into protective custody by members of the network, becoming part of its National Collection of Endangered Plants. They hope to add about 100 more to the collection this year.
The reasons for their effort go well beyond scientific curiosity.
When a plant species disappears, a region loses some of its complexity - its ability to bounce back from disturbances like drought, disease, or fire, and the planet's gene pool is diminished, Falk says. Advances in biotechnology mean that the special genetic qualities of a given plant might be transferred to other plants for the benefit of agriculture or the $7 billion-a-year horticulture industry, or used in science.
Rare plants can also help unlock the mysteries of plant biology and ecology, and many are worth saving because their beauty is part of the nation's heritage, Falk says.
But they are disappearing faster than ever, as human populations claim more once-wild areas for agriculture, recreation, and housing developments, or subject the indigenous plant populations to pollution.
Many plants on the endangered list are relatives of plants that have proven economic value, or have qualities such as the ability to grow in marginal areas or tolerate frost, dryness, or salt.
Until 1984, there was no organized effort to identify and save them. The center got its start that year when Falk and co-founder Frank Thibodeau, who both studied environmental policy and conservation strategy at Tufts University graduate school, got to worrying about how, in Falk's words, ``plants don't get their due when it comes to conservation.''
Public attention is captivated by endangered animals like the panda and the California condor, but there are far more endangered plants than animals, Falk says.
So the pair went to Peter Ashton, then director of the Arnold Arboretum, with their idea for a national network. They focused on local arboretums and botanical gardens for the network, Falk says: ``They're the experts at growing local plants, understanding their biology, and educating the public.''
Dr. Ashton gave Falk and Mr. Thibodeau a home on the top floor of the arboretum's visitor center and the names of a few contacts, and they went to work.
The 19 members of the network divide the US, including Puerto Rico and the Virgin Islands, into 14 zones determined by weather patterns and plant species. Each year, each member submits proposals to the center outlining which species they'd like to focus their protection efforts on. The center's Scientific Advisory Council decides which will be selected.
John Fay, chairman of the advisory council and a botanist with the US Fish and Wildlife Service's Division of Endangered Species and Habitat Conservation in Washington, draws a parallel between the center's network and zoos, saying that both act as modern Noah's arks for endangered species. That function also makes them catalysts in the conservation movement, he says.
But he adds that harboring near-extinct plant species in protected gardens is not a panacea: ``You can't capture all the [genetic] diversity of a wild population in a garden population. It's not the same as having a large population in the wild.''
Once a plant is approved for protection, local botanists secure the permits needed to collect an endangered species, talk to local conservationists about where to find the plant and when it is producing seeds, then embark on field trips to collect seeds or cuttings from as many plants as possible, in order to preserve genetic diversity.
Seeds, cuttings, and pollen are stored in facilities specially built for the purpose, usually regional facilities of the US Department of Agriculture. Some seeds and cuttings are used to propagate about 50 plants in a greenhouse, and when they are hearty enough, they are transplanted outdoors.
The eventual goal, though the program is too young to have done this yet, is reintroduction of the plant in the wild.
The center has a staff of eight people and an annual budget of $600,000, about three-fourths of it foundation grants and the rest from private, group, and corporate donations. Individuals, garden clubs, or others can ``adopt'' one protected species for a $5,000 donation, which covers the expense of propagating and caring for a plant once it is selected for protection, Falk says.
``Theoretically, we can prevent the extinction of any more plant species in the US,'' Falk says. The center has about 900 plants on its ``most endangered'' list, however. Plants on that list are known to exist at fewer than six sites in the wild, or to have fewer than 1,000 specimens left.