(This paper was read before the Niagara Frontier Botanical Society in 1995.)

Most of us know rhubarb only as that sour and somewhat slimy vegetable served to us by people against whom we have no defense: ever hopeful grandmothers and well-meaning hospital dietitians. In fairness, I also know it in combination with strawberries in my favorite pie. That's how it gets its alternate name: pieplant. Good or bad, how in the world can an author fill 250 pages of text and an additional hundred pages of notes and bibliography about this mundane topic? Well, Clifford M. Foust has done so in a delightful book entitled Rhubarb: The Wondrous Drug (Princeton, New Jersey: Princeton University Press, 1992). It is his story that I have condensed and will relate to you in much modified form. It seems to me that his is a tale much worth retelling.

Mundane topic indeed. From page one I found myself completely absorbed in a book that ranges over 4700 years of medicine, geography, botany, pharmacology, economics, horticulture and -- how can we escape it -- politics. By serving as a microcosm, this remarkable plant brings each of these aspects of our social history into sharp focus. The cast of characters is an historical Who's Who: among them the explorer Marco Polo; the missionary Matteo Ricci, about whom a recent best seller was written; the physician Robert Boyle; the botanist Robert Erskine; the pharmacist George Dragendorff; and our own Massachusetts horticulturist Luther Burbank. And the narrative is driven forward by a fascinating detective story. Foust's history classes at the University of Maryland must be packed.

It turns out that the use of rhubarb stems for food and wine has only about a 200 year history (still less in this country) while the medicinal value of its roots made it a very important weapon in the doctor's pharmacopoeia for at least 20 times as long. I must stress here, because my introductory remarks may have misled you, that it was indeed the root of the rhubarb that supplied the medicine, not the stem that we use in cooking and fermenting. Here are some excerpts from a 16th Century description: The roots were black on the outside, some as big as a man's thigh or leg, and when harvested revealed a yellow interior with many veins of fair red. Juices of this root stained the skin yellow. These roots were dug up in the late fall or winter when the plant was dormant, dried for several days in the sun and then hung to cure in the wind but out of the sun for two months. (Later some growers substituted more rapid oven drying for the initial sun drying, but that tended to leave the center of the root moist, encouraging rot.)

The Chinese herbal, Penking, believed to have been written in about 2700 B.C., describes rhubarb among its plants useful for a variety of medical purposes. The written record is thin from then until sixty years before Christ was born, when the Greek physician Dioscorides was proposing its use not only for stomach aches and excess gas but also as an antidote to poisonous animal bites. Within a hundred years the Roman Pliny extended these uses to colds; liver, kidney and spleen ailments; cramps and convulsions; wounds and bruises. Over time others added uterine fluxes, malarial and childhood fevers; mental diseases; dropsy, jaundice, chronic diarrhea and dyspepsia; nerve, chest and asthmatic complaints and fevers; scurvy, psoriasis and even syphilis. It was for this last that Henry VIII was administered rhubarb on his deathbed in 1547.

That remarkably overoptimistic litany of complaints to be served indicates both how narrow were the options of early doctors and what little they had available to contribute to the welfare of their patients. The medicine rhubarb serves simply as a mild laxative. But that is no small thing and it was indeed the cathartic of choice. For example, in Robert Boyle's 1672 therapeutics, we find his remedy for diarrhea and flux of the belly: ten or fifteen grams of powdered rhubarb (a very light dose) mixed with half a dram of dioscordium (the latter drug derived from a wild yam usually used for hepatic diseases and rheumatism). For yellow jaundice, he recommends two drams of rhubarb with a dram each of saffron and mace, and a handful of hemp seed, bruised and steeped in a quart of white wine. (Ah, the pleasures of jaundice.) Finally, he found rhubarb to be a fine purging electuary for children when mixed with "very good Currans." To these doctors, as Faust tells us, rhubarb "addressed a fundamental medical need -- the elimination of unwanted humors from the body -- without, at the same time increasing the pain and misery of the afflicted, as did other drastic cathartics and countless other remedies."

To understand the importance of this use as a cathartic, moreover, we must first remove from our thinking the medicinal chemistry that has developed only over the past century but that has changed the doctor's approach to health care almost entirely. A hundred and more years ago physicians were necessarily much more (some would say even more) like witch doctors and faith healers than like the modern medical practitioner. Their medicines were herbs grown in gardens or collected in the wild and the alternatives to rhubarb too often fell into the category of "heroic" therapies: harsh and painful purgatives like hellebore, tragacanth and senna that left the patient with more serious problems of looseness and diarrhea, or, at the opposite extreme, severe griping. And other interventions were even worse to our modern eyes: a vein cut and blood dribbling into a basin or forced vomiting or the application of leeches.*

Physicians agreed then that rhubarb was a broadly useful tonic. Unfortunately this left them with a serious problem. How do you get it? All that was known about the plant until very recent times was that it was grown somewhere east of the Caspian Sea and the Volga River -- also known as the Ra River from which the name rhubarb is said to have derived. Raw roots were brought to the West first through Turkey and later by way of Russia, in both cases by caravans out of the vast, unknown reaches of Asia. In the late 13th Century Marco Polo reported it grown in a vague location in northern China and the trade routes seemed to confirm this. But where?

Of course the difficulty of obtaining rhubarb drove up its price. In 1542 France, for example, the cost of rhubarb was ten times that of an equal amount of cinnamon and four times that of saffron. At the same time in England its cost was almost three times that of opium. It was a medicine only for the rich. The poor had to substitute much less effective but at least available herbs like rhubarb's relative, dock. In fact, unscrupulous distributors often laced their valuable rhubarb with dock or simply substituted the less valuable herb, thus serving as models for our modern street dealers of drugs.

Until the middle of the 19th century the largest share of quality rhubarb came to the west by way of Russia. What had been shared with caravan routes through Turkey before that time was converted to a monopoly in 1657 when, acting in the name of the tsar, the Russian Great Prince Aleksei Mikhailovich prohibited "under pain of death with no right of appeal and no expectation of mercy," the purchase and sale of medicinal rhubarb by Russians of all classes as well as Siberians, Bukharans and Tatars. Rhubarb that came in over the caravan routes through Outer Mongolia to the Russian border towns of Irtusk and Kiakhta became the tightly controlled property of the tsars. Russian emissaries to China solidified these arrangements by negotiating the first treaty by outsiders with the Manchu dynasty, the 1689 Treaty of Nerchinsk. For many years after this the Russians were the sole suppliers.

Consider with me the tortuous route of rhubarb from the still unidentified Chinese highlands to the pharmacists of Europe. Once the rhubarb was prepared by the growers, it was baled and carried 1000 to 1500 miles up the trade routes and over the Great Wall of China, across the vast Gobi Desert and then the highlands of Inner and Outer Mongolia, through the Mongolian capital of Ulan Bator and finally down the valley of the River Gol to the Russian border towns southeast of Lake Baikal, a trip of many months.

There a Russian apothecary applied the brak, a measure of quality. He looked for signs of softness and rot, color -- deep yellow best, white worst -- and insect damage. Some was simply burned, acceptable rhubarb separated into three grades.

But remember, we're still over 3000 miles east of present day Moscow and 400 more miles from St. Petersburg, another year-long caravan ride in the Middle Ages. That long trek came next.

In St. Petersburg the brak was applied again because the rhubarb was, of course, subject to further deterioration on the long trip. Then it was loaded on ships bound mostly for Amsterdam and it might have enjoyed the next several weeks if it weren't stowed deep in the ship's hold. Out the Gulf of Finland the ship sailed, down the Baltic, through the narrow Oresund into the open Kattegat and Skagerrak, across the Baltic and finally up the Amstel River canal to the Dutch port.

And now the wholesaler purchases the rhubarb for resale and often transshipment of his valuable cargo.

Like most monopolies, this one had its ups and downs. The Russians wanted as much income as possible from their rhubarb. So they urged more from the East and shipped increasing quantities. But that drove the price down. They tried to hold back, but now the rhubarb rotted in their warehouses. It went on like that for two centuries, up and down, good years and bad, but the amount shipped ever mounting over time until it surpassed a hundred tons a year.

Of course, two things that you might well expect happened. First, other traders sought to find ways to compete. And second, horticulturists sought to obtain and grow the plants. Let me discharge the first of those rather quickly.

The British East India Company began in the early 1700s to purchase in China and ship to England small amounts of rhubarb, but they never competed very well with the Russians. Through the 18th century they were still rounding the Horn, an eight month trip each way. They weren't as good buyers in China and were sold poorer quality stock. At sea dampness was a serious problem as were insects, particularly cockroaches. They didn't apply the brak so, when it came time to sell their goods, they found themselves dropping their prices and still not capturing more than about 10% of the market. In some years frigate captains were even given specific instructions with regard to rhubarb: "Bring none."

Of more interest to botanists is the horticultural side of this story.

First, let's attune ourselves. Linnaeus, the great systematizer of botany -- and practically everything else as well -- lived from 1707 to 1778. We can discharge Columbus claim to have found rhubarb on his first voyage -- it was probably Mexican bindweed which has purgative qualities not equal to rhubarb. Even so, it was still a hundred years before Linnaeus time when the first candidate for the so-called "very true rhubarb" was found in present-day Bulgaria. Seeds were sent to London in 1617 where Charles Parkinson raised them and widely distributed successive seeds to friends across Europe. The resulting plants, usually referred to as rhapontic or English rhubarb, produced a very weak medicine that served with dock as the poor man's rhubarb. The English assigned it the name Rhaponticum verum, the species name an unsuccessful attempt to designate it the true rhubarb. It was around for a long time, as almost 200 years later Thomas Jefferson was sent seeds of this plant by European friends.

Then in 1716 -- now we're at least in Linnaeus' time -- James Sherard, a trained botanist, was British consul in Smyrna, now Izmir (a Turkish Mediterranean port my ship visited at the end of World War II.) That year Sherard retired and brought back to England many plants including a homely rhubarb with warty or ribbed leaves. It was this plant that Linnaeus later catalogued as Rheum ribes. Linnaeus' simplified classification scheme encouraged amateur botanists -- anyone could apply it as it simply involved counting stamens and pistols -- and this was also the time of travels into remote lands. These travelers joined the caravans into the East and even though some measures were taken by those who enjoyed control of exports to mislead them in their quest for rhubarb, the explorers came closer and closer until finally late in the last century they zeroed in on the several high regions in western China where rhubarb was grown and cured.

But in the process there were several different species identified. A 1730 variety was called Rheum compactum for its short stalks, a 1734 kind called Rheum undulatum for its long wavy leaves. Then well into the 19th century came Rheum officinale, Rheum palmatum and finally a variety of this last species with the designation tanguticum. Seeds and later cultivars of each of these species were brought back to the west, grown, distributed and usually claimed as the real thing, the very true rhubarb. As we will see, they may well have been, but they still didn't compete with Russian rhubarb.

Today it is generally considered that the best medicinal rhubarb comes from Kansu Province, 800 miles west of Peking and near the end of the Great Wall of China. Second best comes from Shensi province 500 miles southwest of Peking and the third best from Szuchuan Province that lies another 400 miles in the same direction. Since all of those species regularly interbreed, it matters little which variety is indeed the very true; the best candidate, however, is that last, the tanguticum variety of Rheum palmatum.

Pharmacists and chemists ran increasingly sophisticated tests on all of these species. My favorite early test was one applied to what was called Turkey rhubarb: "Half an ounce of this fresh root, thinly sliced and steeped 24 hours in a half pint of gin [was found to be] most agreeable [and] very cordial [but] not much cathartic." It may not have served its purpose but the testers must have at least come away happy.

Several special characteristics of rhubarb finally became clear only in this century. First, seeds did not breed true. Second, even rootstocks did not produce plants in the west that competed with their relatives in China. The climate, the soil, the 10,000 foot elevation, the weather just could not be matched. All those attempts to reproduce the Chinese rhubarb were bound to fail. Horticulture doesn't have all the answers after all.

This brings us finally to our lifetime. Rhubarb continued to be used until chemists synthesized and duplicated the active agents in very recent years. In one of its forms it was a basic ingredient in such patent medicines as Anderson's Pills, Gregory's Powder, Cuticura Resolvent, Morison's Pills and Green's August Flower. Its non-addictive, non-dependence producing, non-harsh properties placed it at the head of a list of competitors that included dried buckthorn bark, May apple, aloe, senna, even liquid paraffin and later Epsom salts, sulfate or carbonate of magnesia and barbiturate of potassium.

But don't head for your gardens to dig out rhubarb roots to replace your Metamucil or ExLax. Those roots probably won't hurt you, but like rhaponticum they won't do you much good either. Luther Burbank obtained a variety of rhubarb from New Zealand for his cultivars and developed them for the food and drink potential of their stems -- their flavor and texture -- and for their rapid growth and long growing season, rather than for the medicinal properties of their roots. Yours are almost certainly descendants of Burbank's plants. So stick to the stalks of your garden plants not the roots, but avoid the leaves as well. Although they were widely used in the last century as table greens, on many rhubarb varieties those leaves are poisonous.

I conclude these remarks with Faust's own final paragraph. It aptly summarizes this remarkable story: "The history of rhubarb is one of chance and circumstance as much as it is one of systematic and steady accumulation of knowledge and skills. The peculiarity of this botanical lay in its inaccessibility and resistance to human control, as I have argued. The final word, though, is that in spite of a seemingly endless string of failures and frustrations, the quest was worth the candle. We have few better examples of a product of nature that contributed so effectively to improving a quality of life for so many people over such a long time."