Science

Linnaeus Canadensis

Almost 300 years ago, the great Swedish naturalist sent an acolyte to discover Canada’s flora and fauna

Carolus Linnaeus, the Enlightenment genius who classified the natural world, was a connoisseur of the north. As a youthful adventurer, he set off for Lapland, the far northern reaches of Scandinavia, where, he noted, the indigenous Sami people prepared reindeer milk eighteen different ways. Crossing into the Arctic Circle close to Sweden’s Jokkmokk region, he became one of the Arctic’s first serious scientific explorers. Although he suffered through clouds of gnats and times of hunger, he found the “savage wilderness” of Lapland entrancing, and he returned laden with rare plants. If summer was shorter there than anywhere else in the world, he wrote, it was “nowhere more delightful.”

Establishing himself in the university town of Uppsala, Linnaeus refused to be defeated by the remoteness of eighteenth-century Sweden. Instead, he made the world come to him. In his quest to name every animal and plant on Earth, he sent out seventeen “apostles” on collecting missions. His men explored Canada, accompanied Captain James Cook to the Pacific, and snuck into a closed Japan. While Linnaeus admired the diversity of tropical species, he took particular delight in the life forms of the north. He granted names to arctic and Canadian wildflowers, to the caribou (Rangifer tarandus), and to Odobenus rosmarus, better known as the walrus.

Three hundred years later, the world is still coming to Linnaeus. I joined the thousands who gathered last May in pastel pretty Uppsala to celebrate his tercentenary, captivated by a man who saw natural science as a form of adventure. In the eighteenth century, the world was new, waiting to be discovered, waiting to be shipped, packed, or carried back to Uppsala, where Linnaeus made order out of chaos.

As befits the enormity of Linnaeus’s fame in Sweden, his 300th birthday jubilee was a lavish affair. Along with Swedish royals, in attendance were Kofi Annan, Jane Goodall, and the Japanese emperor, who is an expert on goby fish. Around town, Peter Max-style banners declared Linnaeus “Mr. Flower Power.” To the Swedes, Linnaeus is an irresistibly romantic figure, key to their nationwide passion for nature. But as I would soon learn from Uppsala scholars, Linnaeus was a complex man, and anything but the dreamy flower power type.

Certainly, Linnaeus’s collecting trips demanded enormous personal sacrifice, and two of the northern ones went badly. Anton Rolandsson Martin reached the island of Spitsbergen with a whaling expedition in 1758, but he got ashore for only three days and made very few discoveries. Another apostle, Johan Peter Falck, committed suicide in Russia. All told, seven of Linnaeus’s apostles died in the field, succumbing to malaria and other misfortunes. Fortunately, the Canadian expedition had a happier ending.

For the North American trip, Linnaeus chose a former student, a botanist named Pehr (or Peter) Kalm. Linnaeus knew precisely what he wanted in a disciple, to the point of sounding coldly manipulative, and Kalm struck him as ideal, being of humble origins, sturdy, indifferent to food, and determined not to fail. “Now is the time,” Linnaeus wrote to members of the Royal Swedish Academy of Sciences, urging them to underwrite the North American expedition. “Another time he will be heavy footed, lazy, and comfortable, and too fat to run like a hunting dog in the forests.”

As his hardboiled imagery suggests, Linnaeus was no dry scientist. Instead, for all his erudition, his sensibility was humorous, even bawdy, and that was part of his brilliance as a teacher. Centuries before the computer, biologists praised Linnaeus as a master of information systems. He knew how to boil down complex facts into human terms, so they could be grasped and remembered.

Prior to Linnaeus, plants and animals had long, unwieldy names that scientists often changed at will. In 1753, Linnaeus revolutionized biology with his book Species Plantarum, which gave thousands of plants two-part Latin names. His brilliantly simple naming system would, within his lifetime, gain near universal acceptance, and it is still used today. Once established, Linnaeus expanded his system to animals, giving all life forms a first and last name just like people. Even non-scientists recognize certain of his Latin names, such as Homo sapiens and Cannabis sativa.

As the father of taxonomy — the classification of organisms — Linnaeus also established the hierarchy of the natural world, from kingdom down to species. And he invented an ingenious system of classifying plants that relied on a controversial memory aid: sex. Observing that a tulip has six stamens — the plant’s male reproductive organs — he declared the species a member of Hexandria, “six husbands in the same marriage.”

Beyond his wit, the true nature of Linnaeus’s character remains open to debate. One could argue, for example, about the meaning of a note Linnaeus wrote in 1751, frustrated that Pehr Kalm had not come to visit upon returning from North America: “Take burning firebrands and throw them at Professor Kalm, so that he might come without delay to Uppsala, for I long for him as a bride for the hour of one o’clock at night.” Was this Linnaeus the passionate (even homoerotic) teacher, longing to celebrate his student’s return to Sweden? Or was this Linnaeus the greedy manipulator, longing to get his hands on specimens of plants still unnamed?

Certain contradictions in Linnaeus’s character are revealed in his relationship with Pehr Kalm. If Kalm did not rush to his mentor’s side upon returning to Sweden, this is entirely understandable, for Kalm had left his Canadian mission unfulfilled.

Not surprisingly, Linnaeus had high expectations for his disciple. He wanted Kalm to bring back unknown New World plants so they could be named and entered into Species Plantarum, Linnaeus’s ambitious global plant encyclopedia. (Although Linnaeus encouraged his apostles to collect both plants and animals, Kalm, as a botanist, focused mainly on the vegetable kingdom.) Linnaeus wanted seeds from those plants for his own botanical garden.

He also wanted Kalm to find plants that would boost the economy of Sweden, particularly a cold hardy mulberry that could feed Swedish silkworms. Further, he wanted Kalm to ignore all peril and travel deep into Canada, as far north as Hudson Bay.

Kalm left Uppsala on October 16, 1747, “in the name of the Lord right after dinner.” Then in his early thirties, Kalm was described, according to Paula Robbins’s new biography, The Travels of Peter Kalm, as “tall and towering and with a manly and agreeable countenance.” From England, he sailed on to Philadelphia, where he met John Bartram, the foremost naturalist in the colonies, and Benjamin Franklin. But his true destination was “New Sweden,” the remnant of a Swedish colony in New Jersey, where he established his base and preached occasionally in the local church.

Kalm may have been content there, but Linnaeus and members of the Royal Academy were getting restless. They had urged Kalm to head up to Canada, where the climate more closely matched that of Sweden, to find plants capable of surviving Nordic winters. In May 1749, Kalm dutifully embarked on his journey north, taking advantage of a lull in the long-running war between the British and French.

Accompanied by his manservant, Kalm travelled up the Hudson River, crossing into what was then New France at Fort St. Frédéric in a borrowed birchbark canoe, with hired men to do the paddling. Near the border, he narrowly escaped an encounter with six “Indians” of an unspecified tribe, seeking revenge against the English for the death of a brother. Kalm, telling the tale in his book Travels into North America, knew he could all too easily have been mistaken for an Englishman. Hearing a “bloodcurdling outcry,” he saw the Indians’ boat pass by, “with a long pole at the front, at the extremity of which they had put a bloody human scalp.”

Yet Canada, for all its terrors, had a sophisticated side. Not long after his brush with death, Kalm found himself in polite Montreal society, where he bought two pairs of silk stockings. In the city of Quebec, he was much impressed with the colonial governor general, the Marquis de La Galissonière, a man so well versed in natural history that Kalm compared him to Linnaeus himself.

Continuing down the St. Lawrence, in early September Kalm reached Baie-Saint-Paul, some eighty kilometres past Quebec City, before deciding to turn back. Although far south of Hudson Bay, which Linnaeus had set as a goal, Kalm was tired of playing voyageur. He went to great lengths to justify his decision to Linnaeus, explaining in a long letter that a trip farther north would be impossible or dangerous, as the region was inhabited by “Esquimaux” who, according to French fishermen, “without mercy kill all.” Besides, “nothing useful grows in the northern part of Canada,” he wrote, the diet being only meat and berries, and the land barren — “five times worse” than the way Linnaeus had described Lapland.

On his way back to New York, Kalm had planned to return via Niagara Falls, but the French barred his passage by that route, evidently fearing he might be a spy. When Kalm finally reached the Falls a year later, he wrote a detailed account that Benjamin Franklin rushed into print as the first description of Niagara Falls by a trained scientist. In a letter to a Stockholm librarian, Kalm measured the waterfall’s drop in French feet, Swedish feet, and fathoms, and noted that the force at its ledge was enough “to make the hair stand on end.”

Before sailing back to Europe, Kalm returned to the comforts of New Sweden, where he married the minister’s widow. Full of hope for the future, he then made his way home to Åbo, Finland (at the time part of Sweden), where he had a professorship. He brought dozens of plants and seeds that, once established in Swedish soil, were certain to bring him fame and revolutionize the country’s agriculture. Or at least that was the picture Linnaeus had painted.

Among Kalm’s North American treasures was a fast-maturing corn from which, he predicted, “more than one barrel of gold will be gained.” He had squash, wax myrtle for making candles, white cedar for fence posts, and sugar maple for producing syrup. He had hardy mulberry trees that promised a breakthrough in the Swedish production of silk. He had medicinal plants, including ginseng, which the French used as a stomachic, and the great blue lobelia, which the Cherokee used against syphilis.

The report Kalm sent to his university administration catalogued the failures that ensued. His lobelia sprouted, “but it did not have time to gain any strength before the severe winter arrived, wherefore it withered.” His mulberries failed to grow “more than a finger regardless of the care I have given them.” Although his squash plants bore “beautiful and ripe fruit,” the Swedes never developed a taste for them. According to Kalm authority Karen Reeds, only two of Kalm’s North American imports ever achieved popularity in Scandinavia: the cockspur hawthorn and the Virginia creeper.

In the end, Kalm lacked what it took to be one of Linnaeus’s favourites. His personality was too bland, his prose too tedious. Published starting in 1753, Kalm’s three-volume Travels into North America is not exactly a page turner, though rich in botanical and sociological description. While only two of Linnaeus’s letters to Kalm survive, it is noteworthy that Kalm stopped writing to his mentor in 1758, presumably because Linnaeus had lost interest in his career.

Perhaps Kalm’s most important legacy is that of names. He brought Linnaeus specimens of at least ninety North American plants, from the black raspberry to poison ivy. Some sixty were new to science, as yet unnamed. Although the great blue lobelia never did cure syphilis, Linnaeus respected Kalm’s story enough to name the plant Lobelia siphilitica. More than a few times, Linnaeus paid homage to Kalm’s Canadian journey, naming wild ginger Asarum canadense (“of Canada,” in reference to the general northeast region), the Canada violet Viola canadensis, and wild onion Allium canadense.

And Linnaeus ultimately did reward Kalm as only he could. He named an entire New World genus of plants, the beautiful laurels, Kalmia. This gesture was due, Kalm humbly wrote, to “the peculiar friendship and kindness with which he has always honoured me.”

The best way to get to know Linnaeus is by heading out into nature. Had I chosen to retrace his path through Lapland, I would have been in for rotten weather and a lot of reindeer meat. Instead I chose a far gentler trail, biking through Uppsala on a beautiful morning in May.

Uppsala is a very green city, with about 160,000 bicycles, nearly one for every resident, and an impressive system of bike paths. For the jubilee, the city created a blue-flagged Linnaeus Trail leading sixteen kilometres out to Hammarby, Linnaeus’s country estate. Two days before his birthday, I set out on my borrowed bicycle, the quaint, upright Swedish kind. My first stop was a famous field where thousands upon thousands of snake’s head fritillaries were in bloom — maroon ones and white ones, their petals patterned in an exquisite checkerboard. Linnaeus believed the plants, which are not native to Sweden, escaped from a nearby botanical garden.

Along my route, signs in Swedish and English indicated spots where Linnaeus once led his students on natural history walks. From time to time, he also organized mass excursions through the countryside, with up to 2,000 people and musicians from the local military marching band. When someone brought him a worthy specimen, the bugler would sound a fanfare, and everyone would come running to hear Linnaeus’s commentary.

Climbing gradually, one reaches the redbrick Lutheran church that Linnaeus attended on Sundays, accompanied by his dog. A few kilometres farther down the same road is Hammarby, where Linnaeus spent summers with his wife and five children in a charming wooden house that still stands, along with his now empty natural history museum. The Siberian crabapple planted by Linnaeus was in bloom; I laid my hand on its 250-year-old trunk. In the rocky garden grows a patch of dog’s mercury — the plant pictured, along with Linnaeus himself, on the Swedish hundred-kronor note. Linnaeus wrote about dog’s mercury while still a student at Uppsala, in an essay called Praeludia Sponsaliorum Plantarum, “On the Foreplay to the Wedding of Plants.” Dog’s mercury has separate male and female plants, a fact that helped Linnaeus conceive his sexual system for classifying flora.

Linnaeus’s system is no longer used by botanists, because by the early nineteenth century scientists considered his classifications too arbitrary, being based solely on a flower’s sexual organs. The modern system groups plants into families according to similarities in their leaves, stems, and flowers. This system, too, is changing. Genetic sequencing has forced botanists to revisit old assumptions about plant relationships, as species that look similar sometimes turn out to have divergent evolutionary histories.

Yet if Linnaeus’s sexual system is outdated, it still works. With a little practice, you can learn to place plants into Linnaeus’s twenty four classes, based on the number and configuration of their pistils and stamens. There is a certain romance to using it, a certain frisson of history. I like traipsing around with a magnifying glass around my neck, peering into the centres of flowers. When you find yourself counting the stamens of a wood sorrel flower on a cloudless spring day in the Swedish countryside, and you say, “Aha, ten — so the species belongs to Decandria, ‘ten husbands in the same marriage,’ ” that’s when you know you have truly entered Linnaeus’s sphere.

I confess, however, that Jokkmokk still beckons. Linnaeus’s sense of adventure remains contagious and difficult to suppress, even for an armchair naturalist like me. On July 1, 1732, Linnaeus reached the Lapland alps, where he watched the sun set on the summit of Harrevarto mountain and wrote, “This spectacle I considered as not one of the least of nature’s miracles. O Lord, how wonderful are thy works!”