Get Involved
About Us
Our Members

Unraveling the Voynich Codex and Flora of the Voynich Codex: An Exploration of Aztec Plants


Unraveling the Voynich Codex by Jules Janick and Arthur O. Tucker. Cham, Switzerland: Springer; 2018. ISBN: 978-3-319-77293-6. Hardcover, 412 pages. $54.99.

Flora of the Voynich Codex: An Exploration of Aztec Plants by Arthur O. Tucker and Jules Janick. Cham, Switzerland: Springer; 2019. ISBN: 978-3-030-19376-8. Hardcover, 353 pages. $219.99.

A review of two recent books that present a detailed case for unraveling the origins and floristic genesis of the Voynich Codex is the type of book review that itself could become a book. Unraveling the Voynich Codex and Flora of the Voynich Codex: An Exploration of Aztec Plants were published in 2018 and 2019, respectively, and both were co-authored by Jules Janick, PhD, the James Troop Distinguished Professor of Horticulture at Purdue University, and the late Arthur O. Tucker, PhD (1945-2019), professor emeritus at Delaware State University.1 The two texts add to the layers of mystery and controversy swirling around the authorship, origins, and content of what has been referred to as the world’s most enigmatic manuscript: the Voynich Codex.

Polish-born antiquarian book dealer Wilfrid Voynich (1865-1930) purchased the codex that bears his name in a lot of manuscripts from a Jesuit order in 1912. He understood the uniqueness of the manuscript and held onto it until his death in 1930, unable to obtain his asking price of $100,000. He bequeathed it to his wife, Ethel Voynich, and when she died in 1960, Anne Nill, a longtime Voynich associate in the antiquarian book business, inherited the manuscript. She sold it to famed antiquarian book dealer, H.P. Kraus (1907-1988) in 1961 for $24,500. Kraus offered it for $160,000, but with no takers, he donated it to the Beinecke Rare Book and Manuscript Library at Yale University in 1969, where today the work known as “Beinecke MS 408” has a permanent home. A full-size reproduction, including the foldout folios, was published in 2016 by Yale University Press, with accompanying interpretive chapters by various specialists.2

Unraveling the Voynich Codex

In the foreword of Unraveling the Voynich Codex, the authors explain that Tucker became interested in the Voynich Codex in June 2012 while studying Latin American herbs and 16th-century codices from New Spain. He observed incorrect plant species identifications by non-botanists in several works pertaining to the manuscript. This led to a collaboration between Tucker and herb expert and former NASA information technologist Rexford H. Talbert in which they identified 37 plants, seven animals, and the mineral boleite, all of which are of Mesoamerican origin. Their original, peer-reviewed article, “A Preliminary Analysis of the Botany, Zoology, and Mineralogy of the Voynich Manuscript,” was published in HerbalGram’s 100th issue in 2013.3 The article “proved a revelation to Janick, who had minor contact with the Voynich Codex” up until that time.4 The collaboration between Janick and Tucker resulted in further plant and animal identifications, and speculative-though-plausible assumptions led them to hypothesize that the Voynich Codex is of 16th-century origin from New Spain, and, ultimately, to the publication of the two books reviewed here.

Unraveling the Voynich Codex lays the foundation for the hypothesis that the codex was created after the European colonization of the American continents, based on hard evidence of plant, animal, and mineral identifications and the previous work of other “Voynichologists.” According to Tucker and Janick, the botanical illustrations, in their crude, two-dimensional depictions, show plants native to the Americas and are comparable in style to those found in the Badianus Manuscript from 1552, titled Libellus de Medicinalibus Indorum Herbis (“Little Book of the Medicinal Herbs of the Indians”; see HerbalGram issue 275). Tucker and Janick admit that their assertions are speculative and that they lack academic expertise in linguistics and astronomy, yet believe that their postulations are plausible.

The 412-page Unraveling the Voynich Codex is divided into four parts. Part I (chapters 1-3) introduces the reader to the Voynich Codex and its origins and provides a possible historical context for the codex in Aztec Mexico and Catholic Spain. Part II (chapters 4-10) lays the groundwork for the authors’ case that the work is of Mesoamerican origins, including analyses of the plant and mineral iconography, identification of animals, and other more speculative stretches of the imagination in map interpretation, astrological illustrations, and other details. In a paper published in 1944, taxonomist Hugh O’Neill identified sunflower (Helianthus annuus, Asteraceae) and a capsicum pepper (Capsicum sp., Solanaceae) among the 359 plant images or “polymorphs” in the codex.6 Tucker and Talbert’s 2013 HerbalGram article identified 37 plant species,3 and a 2016 paper by Tucker and Janick extended the list to 58 identified polymorphs.7 In Part II, they identify two more plants from the Mesoamerican flora.

Part III (chapters 11-13) is a wide-ranging discussion on the topic of “decipherment” with explanations of cryptological analyses, decoding symbols, Mesoamerican languages, and relationships to the cryptic symbols of the Voynich Codex. Decoding the codex remains elusive, but the authors lay out a foundation for understanding the progress, prospects, and problems related to decipherment.

Part IV (chapters 14-16), “The Author and the Artist,” provides the authors’ hypothesis, theories, and evidence pointing to the real possibility that the codex author(s) and artist(s) were post-conquest members of the Aztec nobility, who were trained by Franciscan friars. The Catholic Church created several schools, which trained the sons of caciques (chiefs) from towns close to modern-day Mexico City. The Spanish ruler Charles I (ruling from 1516 to 1556) funded the convent schools where the training took place. The Badianus Manuscript was one product of these institutions. The aim of this section of the book is to “discover if the multifaceted aspects of the [Voynich] manuscript were compatible with the time, place, and history associated with 16th-century New Spain.” In Chapter 14, the authors posit that whoever created the Voynich was a native Mexican polymath with wide interests and many talents.

In Chapter 15, they recount the many claims put forth by various scholars and speculators about the authorship of the Voynich Codex, including Roger Bacon (ca. 1214-ca. 1294), Antonio Averlino (1400-1469), Leonardo da Vinci (1452-1519), Nostradamus (1503-1566), Francisco Hernández de Toledo (1514-1587), John Dee (1527-1608), and Edward Kelley (1555-1597), to name a few! They also provide detailed evidence of the identity of the illustrator.

Chapter 16 summarizes Tucker and Janick’s “Conclusions, Conjectures, and Future Studies.” They are convinced that the Voynich Codex is a Mesoamerican manuscript based on botanical and zoological identification of plants and animals. They convincingly conclude that the depictions of the sunflower and armadillo disprove the assertion that the Voynich Codex is a 15th-century European manuscript.

Flora of the Voynich Codex

The American Botanical Council’s 2019 James A. Duke Excellence in Botanical Literature Award was given to Flora of the Voynich Codex: An Exploration of Aztec Plants. Flora advances the concept that O’Neill’s identification of two Mesoamerican species, sunflower and capsicum pepper, in the Voynich Codex clearly indicates that it is a post-Columbus manuscript. The authors note that this assertion countervails the universally accepted dogma among Voynich scholars and conspiracy theorists that the Voynich Codex is of 15th-century European origin. The authors imply that non-botanist scholars ignore, discount, or explain away the botanical evidence evoked by the two-dimensional botanical illustrations in the work.

In three previous works, Tucker and colleagues had identified 60 species of phytomorphs in the Voynich Codex. In Flora, the number of species with putative identifications increases to 169, with 131 plant images identified from the Voynich Codex herbal section and 41 plants from the pharmaceutical section of the book. Chapter 4 discusses their identification and makes up the bulk of the book (pages 39-220), and Chapter 5 provides an analysis of the botanical findings. The identifications in Chapter 4 include photographic images of the purported associated plant species which show, where appropriate, the live plant, herbarium sheets, botanical illustrations, or comparable 16th-century images. Each entry includes a description with the botanical name and identification; plant distribution; English, Spanish, and, if known, Mesoamerican names; and notes on uses of the plants, including medicinal, culinary, and others. If appropriate, the authors include information about related species. Some plants are identified at the genus level. If the species is questionable, a question mark is inserted in parentheses, and if likely but unconfirmed, they use the abbreviation “cf.” to indicate “compares favorably.”

The authors consulted limited literature regarding medicinal uses of the plants described. For example, for hand fern (Ophioglossum palmatum, Ophioglossaceae), further exploration of the medicinal plant literature would have shown numerous historical uses for the genus. Various Philodendron (Araceae) species have been associated with fish poisons, curare mixtures (paralyzing agents often used to coat poison arrows), and contraceptives in works edited by Richard E. Schultes, PhD (1915-2001), yet the authors write: “Uses: unknown.” The “uses” section is often the weakest point in the individual species entries but opens the door to further explore more wide-ranging medicinal plant literature.


The internet is rife with bloggers and self-proclaimed Voynich experts who, despite scientific evidence to the contrary, continue to hold on to their fanatical beliefs and assertions while leveling persistent attacks on the premise of Tucker and Talbert3 and the two books by Tucker and Janick. All one must do is search “Voynich” to begin the journey down the divergent roads of skepticism, prejudice, and speculation. For some, it is a fulltime pursuit. The stuck-in-medieval-Europe Voynichologists, bloggers, and theorists love to hate the work of Tucker and colleagues, and, in particular, the two works reviewed here, which present the most comprehensive biology-based investigations of the Voynich to date.

Since its discovery in the early 20th century, the Voynich Codex has been analyzed by religious historians, Roger Bacon specialists, early European history experts, conspiracy theorists, space alien devotees, and the hopelessly obsessed. Along with ancillary convincing evidence, Tucker and Janick associate the time period of the manuscript’s creation to post-Spanish conquest of the Aztecs. Clarity of time, place, and subject matter provide the foundational scholarship for further research, and the eventual decryption of the text. These books will serve as a lasting legacy for Tucker and Janick, perhaps equal to that of the Voynich Codex itself.

Steven Foster is an author, photographer, and herbalist who serves on the ABC Board of Trustees.


  1. Bauman H. Arthur Oliver Tucker III: 1945-2019. HerbalGram. 2019;123:78. Available at: Accessed July 21, 2020.
  2. Clemens R, ed. The Voynich Manuscript. New Haven, CT: Yale University Press; 2016.
  3. Tucker A, Talbert R. A preliminary analysis of the botany, zoology and mineralogy of the Voynich Manuscript. HerbalGram. 2013;100:70-75. Available at: Accessed July 21, 2020.
  4. Janick J, Tucker AO. Unraveling the Voynich Codex. Cham, Switzerland: Springer; 2018.
  5. Foster S. The Badianus Manuscript: The first herbal from the Americas. HerbalGram. 1994;27:112-117. Available at: Accessed July 21, 2020.
  6. O’Neill H. Botanical observations on the Voynich MS. Speculum. 1944;19(1):126-128.
  7. Tucker AO, Janick J. Identification of phytomorphs in the Voynich Codex. Hort Rev. 2016;44:1-64.