This is the third in a series of blog posts called “What’s in a Name,” by my colleague Richard Pearce. After thorough research, he explains to us how plants received their common and latin names.
Botanical lore and nomenclature have always been replete with inexactitudes (see for example Monkey Flower and Gooseberry in this series). But these days conjecture can be propagated instantly across the internet, taking up more or less permanent residence as “fact” in the digital cloud.
To a large extent this is what has happened with the legend of Joe Pye. Visit almost any botanical web site and you will learn that “Joe Pye,” a colloquial name for the indigenous Eutrochium purpureum came from a native American medicine man from Salem, Massachusetts who earned fame and fortune curing colonial settlers of typhus with his eponymous herb.
Other sources may add that the name Joe Pye is a phonetic translation of jopi or jopai, supposedly an early native American word for typhus. Still others assert that Joe Pye was a 19th century Caucasian “Indian theme promoter” (these words always appearing in quotes).
Amazingly, printed books on native North American flora—even credible ones—tend to repeat one or the other versions of this story, seldom bothering to provide a reference as to the source, possibly because the authors regard it as fable. One is anxious to know just how much truth—if any—underlies the seductive tale of an early native American who used a native plant to cure foreigners of a foreign disease.
With the help of original sources from the 18th and 19th centuries, now digitized and available online with instantly searchable texts, and a bit of old-fashioned library work, we can begin to separate fact from fancy in the Joe Pye story.
The Beginnings of a Legend
The first use of the term “Joe Pye” as a common name for a plant was in 1818. It appeared in the widely distributed Manual of Botany, for the Northern and Middle States of America: 2nd edition, authored by the famous New England botanist and geologist Amos Eaton, here reproduced from the original:

(Amos Eaton, Manual of Botany, for the Northern and Middle States of America: 2nd edition,1818)
According to Eaton Eupatorium purpureum and Eupatorium virticillatum were known as Joe Pye and Joe Pye’s Weed, respectively. (Eupatorium purpureum is today termed Eutrochium purpureum and E. virticillatum is most likely Eutrochium dubium, Coastal Plain Joe Pye Weed).
Still more information can be found in the 3rd edition of Manual of Botany, published four years later wherein Eaton added this tantalizing footnote:

(Amos Eaton, Manual of Botany, for the Northern and Middle States of America: 3rd edition,1822)
Changes between the 2nd and 3rd edition of Eaton’s book were modest, mostly pertaining to inevitable shifts in scientific nomenclature, making a detailed footnote on the origin of the name Joe Pye conspicuous. For our purposes it contains three important clues.
First, Eaton directly states that Joe Pye is taken from the “name of an Indian,” not a White man posing as one. Second, he places the use of the plant as a diaphoretic (sweat inducer) in western Massachusetts—not in Salem on the eastern seaboard as the Joe Pye legend of today usually asserts. Third, we learn that president Moore of Williams College used a tea made from one or both of the Eupatorium species listed by Eaton to treat his own “alarming” fever.
Zephaniah Swift Moore was President of Williams College from 1815 to 1821. In 1817, Amos Eaton delivered a series of lectures there on botany and geology. Likely, it was during this time that Eaton learned of Moore’s success in treating his fever with “the liberal and continued use” of Joe Pye’s weed.
The nature of Moore’s fever is unknown and we cannot, of course, attribute any efficacy to his herbal brew on the basis of a single report no matter how enlightened the source. However, it is entirely fair to accept the words of two gentlemen who supposed that Moore’s illness had been cured by a plant known to them as “Joe Pye”.
Before Eaton’s Manual of Botany, and for a time afterward, the popular names for E. purpureum were Trumpet Weed, Gravel Root, Gravelweed, Purple Boneset, Purple Thoroughwort, and Queen (or King) of the Meadow, among several others. Today these names are rarely in use and Joe Pye has become the preferred common term for E. purpureum. (“Gravel” alludes to the plant’s other supposed medical use, eliminating kidney stones, or “gravel.”)
Joe Pye as a botanical name reappears in 1828 when the famous botanist Constantine Samuel Rafinesque included it in his Medical Flora: Or Manual of the Medical Botany of the United States of North America. In Rafinesque’s book, Eutrochium purpureum and Eupatorium perfoliatum are both identified as Joe Pye Weeds. The latter species was then as now more commonly known as Boneset.

(Rafinesque, Medical Flora: Or Manual of the Medical Botany of the United States of North America, 1828)
The wording is close to Eaton’s, suggesting that his Manual of Botany may have been Rafinesque’s source. There are no other books in and around this time that use the term Joe Pye for any Eupatorium or Eutrochium species. Not until the 1840s does “Joe Pye” fully and permanently enter the plant lexicon. Botanical catalogues of native plants from that time on, such as the notable works by Mrs. Wm. Starr Dana, Neltje Blanchan, Ferdinand Schuyler Mathews, Britton and Brown, and the eminent Harvard botanist, Asa Gray, all give Joe Pye Weed as the preferred popular name for E. purpureum.

Mathews, Familiar flowers of field and garden, 1895
So, it can be safely asserted that the term Joe Pye—at least in print—originated with Amos Eaton in 1818, was reiterated by Rafinesque in 1828, and finally came into wide use in the latter half of the 19th century.
But if Eaton was the first to use “Joe Pye,” where did he get the name? For the likely answer we must return again to Williams College.
