A Plant by Any Other Name Started This Blooming Mess

It’s a humble little plant, with spindly stalks and delicate leaves shaped rather like fingernail clippings. And it has quite an identity crisis.

The father of modern botany, Carolus Linnaeus, named the plant Poa annua in 1753, deeming it a member of the grass family. That was fine until another botanist found the same wispy tufts poking out of clay soil in the brickyards of Pennsylvania in 1814. He declared it a new species: Aira pumila.

A decade and a half later, someone found the same plant in Peruvian mountains. He, too, thought he had discovered a novelty, and named it Festuca tenuiculmis. The modest grass popped up in the western Himalayas and in the highlands of Ethiopia in the mid-19th century. Each time, it got a new name. It was rechristened yet again in a book on “The Flora of British India” in 1896 and in “Grasses of Japan” in 1987.

All told, Linnaeus’ Poa annua has collected at least 60 names over the centuries.

Multiply that confusion many times over, and you’ll understand why the Missouri Botanical Garden is teaming up with botanists worldwide on a 10-year, $100-million effort to standardize plant names.

Scientists estimate that there are between 250,000 and 425,000 unique plant species in the world. But there are more than 1 million plant names. The resulting confusion is more than an academic nuisance.

Researchers screening plants for useful medicinal or nutritional byproducts find it hard to get a handle on how many species they have studied. If they discover a promising compound in a rare plant from a remote mountain, they cannot tell for sure whether that’s the only source -- or whether the same plant grows in abundance in backyards in Palmdale under a different name.

It’s also hard to say for sure whether a plant is endangered when it could be flourishing elsewhere, incognito.

“Conservationists, pharmaceutical researchers, ecologists, agronomists, anybody who deals with plant names starts tearing their hair out when they get into it,” said Lynn Clark, a botanist at Iowa State University and the president of the American Society of Plant Taxonomists, which deals with nomenclature.

Clark sighed the weary sigh of a professor who has seen too many students glaze over at the mere announcement of another lecture on plant names.

“People get pretty irritated with taxonomists sometimes,” she said.

That’s why the Missouri Botanical Garden has started its “World Plant Checklist” project. The ambitious -- some botanists would say impossible -- goal is to identify every flower, fern, grass, moss and tree in the world and determine its rightful name.

The project is modeled after the global checklist for birds -- only, there are fewer than 10,000 avian species in the world, and just a handful of new birds are discovered each year. The plant population is at least 20 times bigger, and about 2,000 species come to light annually.

“If they could come to some sort of global agreement on the nomenclature, it would be wonderful,” said Gordon Cragg, who heads natural-products research at the National Cancer Institute. “It’s a massive job. Good luck to them.”

Initially, the database would include only basic facts: a plant’s name, its range, any synonyms associated with it, and whether it’s endangered. Eventually, botanists hope to link each entry to photographs, maps and herbarium collections such as the one at the Missouri Botanical Garden, which stores 6 million dried plant samples in a cool, dark library that smells pleasantly like a spice rack.

The garden, a lush oasis of hedge sculptures, rose trellises and Japanese tea pavilions in a gritty St. Louis neighborhood, has received a $30-million grant to jump-start the project from local philanthropist Jack Taylor, the founder of Enterprise Rent-a-Car. Administrators are applying for other private and federal grants.

On a scribbled-filled white board in a conference room, the project’s leaders have planned the enormous resources it will take to put together the database. “45 compiler years,” one note says. “52 imager years.” At the bottom, there’s a final tally: They will need a staff of 32 for at least a decade just to compile and input the information.

That’s not counting the botanists who will do all the research.

Missouri scientists will be working in formal collaboration with the two other top botanical research centers in the world: the New York Botanical Garden and the Kew Botanical Gardens near London. They expect as well to call on obscure-but-erudite scientists around the globe.

“We might send a sample out to an orchid specialist in Burma to ask, ‘How do you feel about these synonyms? Does this growth pattern mean it’s related to this other plant over here?’ ” said Bob Magill, research director for the Missouri Botanical Garden. “It takes a lot of detective work.”

Fortunately, they’re not starting from scratch. Several huge online databases, most notably the International Plant Names Index, have assembled authoritative information, including synonyms, on tens of thousands of plants.

And individual botanists build their careers doing the same, researching a particular family of plants -- the aster, say, or the coneflower -- to determine the proper names of every species within that group.

“There’s a lot of activity in this field going on in the trenches, and there has been ever since Linnaeus,” said Scott Russell, president of the Botanical Society of America and a professor at the University of Oklahoma.

Though the subject might seem dry to outsiders, many botanists get fired up about nomenclature. Their passion is an asset and an obstacle to the Missouri project.

On the plus side, it seems clear that scientists around the world will be glad to pitch in when the database gets underway. The downside is that it will be tough to achieve consensus.

The botanical community breaks into two antagonistic camps: the lumpers and the splitters.

The lumpers would like to winnow the number of plant names; they argue that many grasses and flowers defined as “new” over the years are not distinct enough to merit their own names. The splitters take the opposite view; they regard even minute variations in a plant’s molecular structure, growth patterns or physical appearance as reason enough to declare it an independent species.

Given that basic philosophical divide, some botanists are skeptical that the Missouri initiative will yield a definitive global checklist.

“It’s a laudable goal and it’s a logical goal,” Clark said. “But you want to be sure the final list is flexible” so plants can be given new names or merged with existing species as the latest research warrants.

In other words: “We’ll never be done,” Clark said.

She didn’t sound too upset. “That’s what makes this interesting,” she said.