Sierra Magazine

Undaunted Botany

Even while struggling to survive, Lewis & Clark took time to stop and name the flowers.

By Colin Chisholm

Popular depictions of the Lewis and Clark expedition focus on encounters with vast herds of buffalo or battles with grizzly bears. Yet the naturalist-adventurers were more often quietly preoccupied by the continent's flora, so meticulously documenting every plant new to them that 200 years later we can view the journey through a botanist's eyes. For this we can thank polymath President Thomas Jefferson, one of the young nation's most accomplished naturalists. Of all the sciences, Jefferson favored botany, reasoning that plants provided "the principle subsistence of life to man and beast." After hiring Meriwether Lewis as his personal secretary in 1801, he began training him in Linnaean classification. (Lewis's prior botanical knowledge was gleaned from a childhood tramping through the Virginia woods with his mother, Lucy Meriwether, a talented herbalist.) In 1803, after choosing Lewis to head the Corps of Discovery, Jefferson sent him to Philadelphia for a crash course with the renowned botany professor Benjamin Smith Barton.

In a letter of introduction, Jefferson wrote of Lewis: "It was impossible to find a character who to a compleat science in botany, natural history, mineralogy & astronomy, joined the firmness of constitution & character, prudence, habits adapted to the woods, & a familiarity with the Indian manners & character, requisite for this undertaking. All the latter qualifications Capt. Lewis has. Altho' no regular botanist &c. he possesses a remarkable store of accurate observation on all subjects of the three kingdoms, & will therefore readily single out whatever presents itself new to him in either."

History confirmed Jefferson's judgment, given Lewis's success not only as an expedition leader but as a field botanist. In all, Lewis recorded 177 plants considered new to science. (Clark noted only one.) Lewis was so eager, in fact, that he collected his first new plant before the corps had even shoved off from Camp Wood near the mouth of the Missouri River, in May of 1804. This was the Osage orange (Maclura pomifera); the thorny cuttings he sent to Jefferson came from trees transplanted from an Osage Indian village 300 miles to the west. The fruit, Lewis said, was "the size of the largest orange, of a globular form, and a fine orange colour. . . . So much do the savages esteem the wood of this tree for the purpose of making their bows, that they travel many hundred of miles in quest of it."

For months to come, the lives of Lewis and his men would depend on the botanical skills of the Native Americans. After the party's first encounter with the Teton Sioux in September of 1804, for example, Lewis wrote of the tribe's use of the prairie apple (Psoralea esculenta), a root that he found unpleasant but that "our epicures would admire. . . . it would serve them in their ragouts and gravies instead of the truffles morella." Two weeks later Lewis smoked Indian tobacco (Nicotiana quadrivalvis) with the Arikara Indians, noting that "it does not affect the nerves in the same manner that the tobacco cultivated in the U'S dose." Lewis sent Jefferson a sample, apparently with future commerce in mind. Likewise with the sticky currant (Ribes viscosissimum), which Lewis described as "really a charming fruit and I am confident would be preferred at our markets to any currant now cultivated in the U. States."

Beyond extending scientific knowledge, Lewis had very practical reasons for paying close attention to edible plants. As the corps worked its way up and over the Continental Divide (near present-day Lolo Pass, Montana), the 31 increasingly ravenous men and their guide, Sacagawea, had already butchered several horses and were almost out of meat. Without the help of the Nez Perce Indians, starvation might have put an end to the expedition long before it reached the sea.

The most significant of the edibles, camas (Camassia quamash), was eaten during the first of many friendly encounters with the Nez Perce along Idaho’s Clearwater River. After weeks without adequate nourishment, the men gorged themselves on the plant’s roots, which the Nez Perce steamed in earth-dug ovens; they had, Lewis reported, a “sort of sweetish taste and much the consistency of roasted onion.” Soon after the feast, however, Lewis and several of his men became violently ill. “This root is pallateable but disagrees with me in every shape I have ever used it,” he wrote, although some authorities believe the men’s sickness was caused by the abrupt change from an all-meat diet. Despite Lewis’s unpleasant experience, on the way home the following spring he would still describe a field of blooming camas as “a lake of fine clear water.”

Moving into the Northwest after Lolo Pass, Lewis began encountering numerous unfamiliar tree species. These included sitka alder (Alnus sinuata), western larch (Larix occidentalis), whitebark pine (Pinus albicaulus), lodgepole pine (Pinus contorta), and—most important for the expedition—ponderosa pine (Pinus ponderosa). Lewis described in his journal how, during times of famine, the Indians collected the black lichen (Bryoria) that hangs like hair from ponderosa branches. When Lewis came across several ponderosa pines stripped of their bark, Sacagawea explained that Indians had done so in order to get at the soft, edible undersides. It’s not known whether Lewis and his men sampled this food, but they did fashion the pine logs into badly needed dugout canoes.

After traveling more than 4,000 miles, in November of 1805 the expedition finally arrived at the Pacific. There they built Fort Clatsop and wintered near the outlet of the Columbia River. From December through March, Lewis recorded upwards of three dozen plant species, including the grand fir (Abies grandis). He was especially taken by the huge conifers that surrounded their fort, unlike any he had seen in the east. The Sitka spruce (Picea sitchensis), he wrote, “grows to imence size. . . . in several instances we have found them as much as 36 feet in the girth or 12 feet diameter perfectly solid and entire. they frequently rise to the hight of 230 feet, and one hundred and twenty or 30 of that hight without a limb.” Closer to earth he noted the western bracken (Pteridium aquilinum pubescens), its root “much like wheat dough and not very unlike it in flavour, though it has also a pungency which becomes more visible after you have chewed it for some time; this pungency was disagreeable to me, but the natives eat it voraciously.” The fruit of the salal (Gaultheria shallon) was prepared by the Indians in much the same fashion as the evergreen huckleberry (Vaccinium ovatum), the berries mashed and dried in large cakes weighing as much as 10 or 15 pounds. Combined with salmon, these and other plants provided the Chinook Indians with more than enough to share with the Corps of Discovery until the expedition departed the following spring.

During the corps’ eastward push in the spring of 1806, Lewis collected more than 70 new plants, including modern favorites such as salmonberry (Rubus spectabilis) and balsamroot (Buphthalmum sagittatum). The Nez Perce taught them to prepare and bake the roots of cous (Lomatium cous) like bread. Cous and dog meat, sometimes eaten together, strengthened the party as they approached the mountains. Lewis wrote that “the flavor of this root is not very unlike the gensang. this root they [the Nez Perce] collect as early as the snows disappear in the spring.”

By July 1 the corps had made it over the still snowy Continental Divide, just in time for Lewis to record the Bitterroot Range’s namesake, Lewisia rediviva, with its fleshy, low-slung leaves and ephemeral, light-pink flowers. Lewis took home six bitterroot specimens, which he later gave to botanist Frederick Pursh, who named the genus after Lewis. (Clark got his own genus too—Clarkia pulchella, the ragged robin, collected on June 1, 1806, by Lewis.) Two hundred years later, those same specimens bloom in Philadelphia’s Lewis and Clark Herbarium.

On the long journey home Lewis was accidentally shot in the left buttock by one of his men while hunting along the Missouri. “As writing in my present situation is extremely painfull to me,” Lewis wrote, “I shall desist untill I recover and leave to my frind Capt. C the continuation of our journal. however I must notice a singular Cherry [the pin cherry, Prunus pensylvanica] which is found in the Missouri in the bottom lands about the beaver bends. . . .”

In South Dakota two weeks later, August 29, Lewis paused to collect one of his final specimens, the pink cleome (Cleome serrulata). He had recorded it two years earlier, but after two years and 7,000 miles by foot, horse, canoe, and keelboat, Lewis still maneuvered his vessel to the Missouri’s shore in search of one last flower.


Colin Chisholm lives in Missoula, Montana. He is author of Through Yup’ik Eyes: An Adopted Son Explores the Landscape of Family (Alaska Northwest Books, 2000).

Up to Top