Get Involved
About Us
Our Members

Siri Sylvia Patricia von Reis: 1931–2021


Siri von Reis, PhD, a Harvard-educated ethnobotanist, author, poet, and fashion model of Swedish and Finnish ancestry, died at home in New York City on August 3, 2021, at age 90. She is known for her published work on hallucinogenic plants in the genus Anadenanthera (Fabaceae) and for authoring multiple works in which she, with the help of colleagues, compiled and organized information from thousands of dried plant specimens from the herbaria (systematically arranged collections of preserved plants and associated data for scientific study) of Harvard University and the New York Botanical Garden (NYBG).

Siri was born on February 10, 1931, to Gustav and Donna von Reis of Bloomfield Hills, Michigan. Her father was the president of Detroit Broach and Machine Company of Rochester, Michigan, and, in 1953, Sweden honored him with the knighthood of the Royal Order of the Northern Star for his efforts promoting Swedish-American relations.1

Siri earned a bachelor’s degree in botany from the University of Michigan in Ann Arbor in 1953. She then attended Harvard University, where she earned a master’s degree in biology in 1957 and a PhD in 1961.1 Between 1962 and 1972, she was a research fellow at the Harvard Botanical Museum, which historically has specialized in the study of economic botany (including ethnobotany), paleobotany, and orchidology. 

In June 1963, she married Arthur G. Altschul (1920–2002), a partner of Goldman Sachs Group, board chairman of General American Investors Company, Inc., member of the prominent Lehman banking family, philanthropist, and art collector.1 Siri’s work often was published under the name Siri von Reis Altschul.

In the book Green Medicine: The Search for Plants that Heal (Rand McNally, 1964), author Margaret Krieg called Siri “the botanist from Bonwit’s,” referring to the now-defunct, high-end department store. Siri was “the only botanist in the world who was a high fashion model while preparing a [Harvard] doctoral thesis [in botany]…. [I]t was a case of being in the world of Christian Dior and Balenciaga by day and delving into the literature of [hallucinogenic] parica, yopo or cohoba snuff at night,” Krieg wrote.

Starting with her doctoral thesis, Siri extensively studied the literature on psychoactive Anadenanthera trees, which grow primarily in savannas but also in the Orinoco rainforest of South America. For millennia, native peoples of the Caribbean and South America have used the bark, seeds, leaves, and other parts of these trees for ceremonial, divinatory, medicinal, and other purposes. The plants are prepared primarily as snuffs, but also smoked, used in enemas, and fermented as a beverage called chicha. The snuffs have many names, including cebil, cohoba, vilca, and yopo. During his second voyage (1493–1496), Christopher Columbus reportedly observed native people using the snuff on Hispaniola in the Caribbean. Later explorers of South America, including Charles-Marie de la Condamine (1701–1774), Alexander von Humboldt (1769–1859), Richard Spruce (1817–1893), and Richard Evans Schultes, PhD (1915–2001), made additional observations.

However, after centuries of reports about these plants, many questions remained until Siri’s research on the subject, which resulted in her monograph The Genus Anadenanthera in Amerindian Cultures (Botanical Museum, Harvard University, 1972). Over six years, she examined almost 450 sources and received about 60 personal communications on the ethnobotany of Anadenanthera alone, a significant undertaking before the internet. In this work, she compiled and interpreted information on the identity, preparation, and native uses of these plants. The work also includes a brief phytochemical and pharmacological review. Siri also revised the taxonomy of the genus and included two species: A. peregrina and A. colubrina. At one time, some psychiatrists who were studying the medicinal potential of chemicals from Anadenanthera considered Siri’s monograph to be “the most complete and authoritative work” they had seen on the subject.

The May 1977 issue of Scientific American featured Siri’s cover article, “Exploring the Herbarium.”2 In the article, Siri wrote:

Some years ago, it occurred to me that the world’s herbaria constitute an accessible and immensely rich source of information on plants with potential food or medicinal value. There are about 1800 public herbaria in the world, housing upward of 175 million dried and pressed specimens that represent the approximately 250,000 different known species and some others not yet identified. I had seen enough of such collections to know that in some instances the field notes attached to a specimen included ethnobotanical information: data on local lore pertaining to the plant and the uses to which it is put by the indigenous peoples of the region. I recognized that for the taxonomists and students of plant evolution who traditionally work in herbaria such information must often appear to be peripheral and incidental, so it would be for the most part overlooked. I decided to pursue the matter. A five-year exploration of the collections in Harvard University’s Gray Herbarium and Arnold Arboretum convinced me that valuable data, gathered and recorded over several hundred years and from all parts of the world, are there on herbarium labels, waiting to be brought to light.

This search, which was completed in 1966, involved examining the estimated 2.5 million specimens of flowering plants in the combined collections of the Gray Herbarium and Arnold Arboretum, and it retrieved notes of health and medical interest on more than 5,000 plant species. Siri compiled and organized these previously unpublished botanists’ notes in her book, Drugs and Foods from Little-Known Plants: Notes in Harvard University Herbaria (Harvard University Press, 1973), a unique source of investigational leads on medicinal and edible plants.

New Plant Sources for Drugs and Foods from the New York Botanical Garden Herbarium (Harvard University Press, 1982), which Siri co-authored with Frank J. Lipp Jr., PhD, followed the same format but resulted from examining the labels of more than three million specimens of flowering plants in the NYBG Herbarium. This search, which started in 1975, took a little more than two years and found more than 4,500 species that are included in the book. Many ethnobotanists still regard these two books as important references.

Siri’s last major contribution to the field was Ethnobotany: Evolution of a Discipline (Dioscorides Press, 1995), which she co-edited with Schultes, the “Father of Ethnobotany.” Through his ethnobotanical research, Schultes helped launch the “Psychedelic Renaissance,” and he previously exemplified Siri’s belief in the potential importance of herbarium data when he found a note attached to a specimen that led him to realize that native people of Mexico were consuming psychoactive mushrooms (primarily in the genus Psilocybe [Hymenogastraceae]). Schultes and Siri’s book included 36 articles by notable figures including Albert Hofmann, PhD, who first synthesized LSD and isolated psilocybin, and Robert Gordon Wasson, a founder of ethnomycology (the study of the historical uses and sociological impact of fungi).

Mark Plotkin, PhD, an ethnobotanist, author, and president of the Amazon Conservation Team, wrote: “Every ethnobotanist must be a boundary walker, typically straddling the divide between academia and tribal cultures. Siri von Reis went one better: she was also a top fashion model…. Her research on the hallucinogenic snuffs of the Neotropics and her compilation of ethnobotanical details from the herbaria of both Harvard and the New York Botanical Garden were both groundbreaking efforts” (email, September 13, 2021).

Michael J. Balick, PhD, vice president, director and philecology curator of the Institute of Economic Botany at the NYBG, knew Siri. “In her role as an associate of the Botanical Museum of Harvard University and honorary curator of ethnobotany at The New York Botanical Garden, Siri von Reis and collaborators inventoried the herbaria at these distinguished institutions,” Balick wrote (email, September 15, 2021). “She cataloged the uses of plants that she found and compiled these into two significant volumes, both published by Harvard University Press. This was a remarkable achievement in an age that predated [the widespread use of] personal computers, databases, and the internet, and was made possible only by hand searching through millions of herbarium specimens to assemble the ethnobotanical notes that generations of field botanists had made — a process that took many years of precise scholarship.

“As a PhD student of Richard Evans Schultes, Siri produced a magnificent work on the genus Anadenanthera and its use in Native American cultures,” Balick added. “This monograph is still widely used by scholars and others who are interested in entheogens (substances that produce an unordinary state of consciousness for religious or spiritual purposes). She was an important figure in ethnobotanical scholarship, and at the same time, always friendly, easy to talk to, and modest about her accomplishments. It was a pleasure to spend time with her and discuss the past, present, and future of ethnobotany. She will be missed.”

Arthur Altschul Jr., Siri’s son, wrote: “Mom considered Richard Schultes her professor, mentor, close friend, and long-time collaborator for almost her entire professional career, starting in Cambridge. Schultes was a looming, larger-than-life character, even in our childhood and as we grew up, and we would see him randomly when he was in New York or Connecticut and would come by to visit Mom and see the family. I would say that no other individual played as much of a role in, or had such an influential impact on, Mom’s professional scientific career. There were many others for whom Mom had deep respect, and with whom she (and often we all) shared friendships, including Robert Gordon Wasson, Frank Lipp Jr., and others” (email, September 21, 2021).   

Siri also served on the editorial board of the Journal of Ethnopharmacology and was a fellow of the Linnean Society of London, which is dedicated to the study and dissemination of information about natural history. In 1983, she received the Distinguished Service Award from the NYBG. A poet, Siri authored The Love-Suicides at Sonezaki: And Other Poems (Zoo Press, 2001) and was also passionate about classical music and art. She is survived by her children, Arthur Altschul Jr., Emily Helen Altschul, and Serena von Reis Altschul; and three grandchildren.


The author would like to thank Mark Plotkin, PhD, and Samantha D’Acunto, reference librarian at the NYBG, for providing information for this article.


  1. Bachrach B. Father Is Escort of Siri von Reis at Her Wedding; Harvard Research Aide is Married Here to Arthur G. Altschul. The New York Times. June 12, 1963. Available at: Accessed September 17, 2021.
  2. von Reis Altschul S. Exploring the Herbarium. Scientific American. May 1977;236(5).