Hedging Bets with Frozen Seeds

A quarter of the world’s plant species may not exist in 50 years, so in Britain they’re taking precautions

  • Tara Mack - Photographs by Bryan and Cherry Alexander
  • Nov 01, 2000

Rosemary Fitzgerald spots the first one within 10 feet of where she´s parked her car: a bright red berry in a prickly, gray-green bush. This is a good omen. Amateur botanists in the area had warned she might not find any berries at all.

FitzGerald - layered in fleece, cotton and wool to keep out the December chill - snakes her hand through the spiny stems to pluck it. When she pinches the berry in her fingers, out pops the treasure she seeks - three moist seeds.

A rare-plant specialist, FitzGerald is one in a small army of plant enthusiasts, mostly volunteers, who for the last three years have been crawling under brush, rappelling down cliffs and wading through streams in an effort to collect the seeds of every seed-bearing plant in the United Kingdom. She is in the front line of an £80 million ($120 million) project - called the Millennium Seed Bank - to preserve genetic materials by freezing seeds, which can be germinated years later if the wild plants vanish.

Her search has brought her to the New Forest in Hampshire, England, a swath of nature preserve near the southern coast. Its name is deceptive. The New Forest has served as deer-hunting ground for the Crown since William the Conqueror laid claim to it in 1079. Much of it is occupied not by trees but by spongy pastures where ponies graze amid fields of lumpy brown heather.

The seeds she is looking for belong to a plant called butcher´s broom. They are among the last seeds of about 1,400 British plant species to be collected in the first phase of the project, which is now virtually completed. A second phase, which has already started, involves similar collecting from dry lands worldwide. The goal is to gather seeds from 10 percent of the Earth´s flora by 2010, 25 percent by 2025.

Plants in Britain and around the world are in trouble, threatened by everything from encroaching human populations to pollution. Scientists predict that 25 percent of the Earth´s plant species may not exist in 50 years. The bank is a pragmatic response. It acts as a genetic insurance policy.

Finding and harvesting all these seeds is not as easy as it might seem. Some plants don´t flower every year. Others live in difficult-to-reach places. Still others may bloom during a narrow period of time. And those are just the ones you can see. Microscopic seeds present a whole new set of problems.

On this winter afternoon, FitzGerald is tromping through the mud in a patch of the New Forest called Standing Hat. This bit really does look like a forest; it is filled with oak trees whose naked branches seem to scrape the gray sky. Because butcher´s broom is a late bloomer, FitzGerald had to wait until December to begin collecting.

As predicted, few of the scraggly bushes have berries. Every now and then she bends down to collect one or two. But after an hour her cloth bag has only about a dozen, which will yield roughly 36 seeds. Although the seed bank recommends gathering no more than 20 percent of the seeds available so as not to damage the plants´ ability to reproduce, FitzGerald takes most of what she finds, figuring that for every bush she sees, there are several that she never notices.

In the early going of the collecting phase, the seed bank asked for thousands of seeds from each species. But plants such as butcher´s broom are rare and hard to find. "Now, to be able to tick the box for some species, they´ve had to come down to quite small numbers," FitzGerald says.

Once workers collect the seeds, they mail the specimens to Wakehurst Place, headquarters of the Millennium Seed Bank. Packages usually land on the desk of Steve Alton, the UK coordinator. They arrive in his cubicle in varying conditions. One parcel, which was dripping with juice, had a note from the Royal Mail attached apologizing for squishing it.

Wakehurst Place, located in West Sussex, 43 miles south of London, is the rural outpost of the Royal Botanic Gardens, Kew. Its 500 acres of gently undulating terrain feature formal gardens, an Asian heath garden, a winter garden and an ancient woodland. The offices are housed in a gray, sandstone mansion built in 1590, the family home of what was once a large estate. The bottom floor still has a wide wooden staircase, carved ceilings and an ornate fireplace. But the second floor has been transformed into a network of white-walled offices and laboratories. Since 1974, conservationists have been studying and storing seeds there.

When the seeds arrive, Alton takes them down the hall through an air lock to a room that is kept at 15 percent relative humidity, roughly as dry as the Arizona desert. The room resembles a post office, with piles of envelopes and packages lying in plastic trays. One has a note from an irritated collector that says, "Another horrible to handle species." The seeds usually rest there for at least a week drying out.

Once they are dry, they go to a lab where biologists pour them through sifters and air blowers to separate the seeds from the leaves, dirt and twigs. If there are enough seeds, the scientists remove a small sample to run some tests. "One of the things we have to make sure we can do is get these seeds to germinate, because there´s no use in storing large quantities of seeds if we can´t do anything with them," Alton says.

He walks into a narrow room with large cabinets. Inside these cabinets, scientists can simulate a seed´s home climate - length of day, temperature, humidity - to coax it into growing. Another sample goes to be X-rayed, which will show if the seeds are healthy or if there are any insects inside.

Some seeds don´t like being dried out, particularly those from tropical environments outside of Britain. These recalcitrant seeds are sent to a special laboratory, where biologists try to find the best way to store them.

Once the seeds have been cleaned, dried and photographed, they are carried outside to a modern, one-story brick building that houses the seed bank. Two doors whoosh visitors through another air lock into another low-humidity room where seeds wait to go into the bank and employees prepare themselves for the minus-4-degree Fahrenheit temperature inside it. Jenny Sandell, a seed bank assistant, dons a full-body blue thermal suit, gloves and a hat that Velcros under her chin. She´s about to search for a seed they are having problems germinating.

Sandell leans into the heavy, heated door and steps inside. In front of her are neat rows of metal drawers on rolling stacks, like the kind you might find at a library. Despite the cold, the low humidity keeps the shelves free of frost. She can´t see her breath, and even her oval glasses take a while to fog up. Sandell moves quickly once she is inside. It´s so cold in here that workers are told to stay for no longer than 10 minutes to avoid hypothermia.

The bank, about the size of a bedroom, holds more than 200 million individual seeds, representing nearly 4,500 species from around the world. Scientists estimate the seeds can remain intact in this environment anywhere from several decades to several millennia, depending on the seed.

Since the launch of the Millennium Seed Bank project in 1997, storage space has been running out. In 1998, construction of a bigger, more high-tech seed bank began. Wakehurst´s new facility, an £18 million ($27 million) storage and research complex, is about 300 yards away from the 16th century house. The building is all metal, glass and concrete - six shiny tubes that appear to be half buried in the ground. It´s nestled in a depression in the hills to preserve sight lines at Wakehurst. Only a tiny portion of this complex holds seeds. The rest is used to house a visitors´ center, a greenhouse and laboratories, complete with lecture space and dormitories for visiting scientists. It opened to the public in August.

Britain is uniquely suited to this kind of seed-gathering project. "The UK is a fairly small geographical area," Alton says. "The flora isn´t enormous. There are about 1,400 species, a manageable number. And it´s got the advantage of being incredibly well studied. Every square inch of the British Isles seems to have been visited by an amateur botanist. You can´t go anywhere without finding some weekend enthusiast surveying the plants. So there´s all this information about where things grow."

When the project started, Wakehurst already had 579 UK species in the bank. Its goal was to collect another 800. There are still about 32 species to collect.

The second phase of the project, targeting dry lands, will focus on Africa, South America and the United States. Seed bank organizers are interested in these arid and semiarid regions of the world in part because the seeds are more amenable to drying for storage, says Alton, and in part because one-sixth of the world´s population lives in these areas. The bank is focusing on species with social value - wild plants used as medicine or food or firewood.

Use of the collected seeds need not wait until a plant goes extinct. In fact, the seed bank will operate something like a financial bank. Researchers will be able to make small withdrawals for everything from medical research to pollution studies to reintroduction into the wild, Alton says.

But what happens to the seeds after they leave the bank is a sticky issue. Gary Nabhan, cofounder of an Arizona-based program called Native Seeds/SEARCH, is worried that businesses could use the seeds for commercial purposes without sharing profits with the communities where the seeds originated. "I´m actually opposed to the idea of a centralized seed bank," he says. "We need to have regional and local seed banks that literally keep things in their habitat rather than transplant-ing them to backup storage and greenhouses. The main point is to have plant diversity as part of people´s lives, not stuck away in some lab."

Some environmentalists in Britain, even those who applaud the Millennium Seed Bank, have similar reservations. Craig Bennett, a wildlife campaigner for Friends of the Earth, is concerned about how the collection might be interpreted by the public, which could see it as a replacement rather than a backup for habitat conservation. Why preserve a meadow or a forest when we´ve got all their seeds in a bank? "We must make sure the politicians don´t just assume that conservation is about keeping two of every species, as it were, a Noah´s Ark approach," says Bennett. "We have to make sure that we have large areas of viable habitat where species can perform their ecological function."

Peter Marren, a botanist and author of Britain´s Rare Flowers, warns that even plant specialists may become too reliant on the bank. "When a plant becomes extinct locally it´s sending us a message," he says. "It´s saying that circumstances are no longer suitable for this plant that´s been there at least 10,000 years in all probability. Instead of jumping to the nearest seed bank, we should be asking ourselves what it is that extinct plant is trying to tell us."

Alton is the first to agree with these types of concerns. The bank, he says, is in the process of negotiating agreements with countries where it hopes to collect seeds. Those agreements will ensure that the nations where plants grow will have a share of any profits made from the materials the program takes. The exhibits in the seed bank´s visitors´ center also will emphasize the link between the seeds in the bank and their natural habitats, he adds. "You can have all the seeds in the world," Alton says, "but if there´s no habitat for those plants to go back to there´s no point in storing them."

And there´s no point in worrying about any of this if nobody can find the seeds in the first place. That´s why the bank has asked free-lance naturalists like FitzGerald to get the last few pernickety species. But even professionals like her have a difficult time collecting certain seeds.

FitzGerald is just about to give up on finding more butcher´s broom. She has moved from Standing Hat to another part of the New Forest called Ivy Wood. This patch is appropriately decked out for the season, filled with holly trees and winding ivy. She has been searching for two hours and still has fewer than 25 berries. And now rain is beginning to fall. "Working in conservation, one has this massive sense of helplessness most of the time," she says.

She decides to make one last check, poking her head into a spot where the holly and the ivy form a secluded cove. Suddenly she is smiling. "Oh, look at this," she says. "This is the one we´ve been waiting for." Shrouded in bracken and blackberry brambles is a bush dangling dozens of berries like Christmas tree ornaments. She grabs them quickly and soon her bag is filled with nearly 75 berries. Not a bad haul, considering she wasn´t sure she would get any at all.

As she leaves, FitzGerald says thank-you to the butcher´s broom for giving up its berries, knowing that if it ever goes extinct, she and the seed bank may be able to return the favor.

London­based writer Tara Mack is a former reporter for The Washington Post.

Bryan and Cherry Alexander, who specialize in polar region photography, live in Dorset, England.

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