Plant Messengers: A Diverse Panel of Experts on Psychoactive Plants

A Gem from our Vaults: A Historic Session from 1992

The following are edited excerpts from “Plant Messengers” a panel held at the 1992 Bioneers Conference.

This panel has to be one of the most remarkably diverse and unusual gatherings of experts on psychoactive plants ever assembled on one stage: Andrew Weil, MD, perhaps the world’s most famous holistic/integrative physician; Marcellus Bear Heart Williams, a Muskogee medicine man and member of the Native American Church; Edison Saraiva, MD and Florencio Siquera de Carvalho, two of the earliest representatives of the Uniao do Vegetal Brazilian Church to visit the U.S.; Kathleen Harrison-McKenna, an intrepid ethnobotanist, artist and plant woman extraordinaire; and Dennis McKenna, Ph.D. and Charles Grob, MD, two of the world’s leading research scientists studying psychoactive plants.

Dr. Edison Saraiva: I am a physician and homeopathic doctor in Brazil, and I work in the area of eco-toxicology, the toxicity of the environment as it affects human beings, and I also do research on nutrition. I’m part of the Uniao de Vegetal church. I have been drinking hoasca (aka ayahuasca and also called vegetal) for eighteen years. During this time I’ve lived partly in the Amazon area and I’ve worked with the ministry of the interior of a regional area of northwestern Brazil. Throughout these eighteen years, I’ve been drinking the hoasca tea, and I find it helps me to balance my governmental work and my inner life. It is interesting how one can inhabit these two different realms of reality and maintain excellent mental health. The hoasca, when well administered, brings the ability to transform the subtle, non-material world into something very palpable.

Kat Harrison: I’m the President and Project Director of Botanical Dimensions, a nonprofit organization I co- founded for the purpose of collecting, protecting, propagating and understanding plants of ethno-medical significance (including shamanic plants) and their lore. Part of my intent is to broaden our cultural definition of what healing is and what healing plants are, what medicine is, and to incorporate the shamanic plants into categories our culture is gradually accepting in terms of herbal medicines. Botanical Dimensions operates an ethno-botanical garden in Hawaii and another in Peru. I’ve explored these various plants and substances extensively over the last twenty-some years in several cultures throughout the Americas.

Dennis McKenna: I’m also associated with Botanical Dimensions as a research director. If you look at cultures in which shamanism has a strong tradition, almost invariably you find that that tradition is centered on the use of one or more powerfully psychoactive plants. I did my graduate research in ethno-botany in Peru in the early ‘80s, studying ayahuasca, and I came away from that experience with the intuition that this was really a very interesting drug or plant complex, and that it and the methods of the traditional healers who used it were worthy of investigation from both a medical and an ethno-botanical point of view. I found that many of the ayahuasceros I encountered in my field work, who had used ayahuasca on a regular basis, some for most of their adult lives, far from being what we think of as impaired by drugs, were actually extremely mentally well balanced, physically healthy people who were extremely high functioning and actually seemed to have derived a lot of benefit from their incorporation of ayahuasca into their lives.

I realized that we didn’t really know anything about the pharmacology of this drug in humans. We knew a great deal about the chemistry of the plants and their effects on animals, but animal models are not really adequate to describe how these things work in humans. I had long wanted to do a biomedical study of long-term ayahuasca users, but it simply wasn’t feasible to do such a study with traditional indigenous populations or jungle dwelling mestizos, the main users of these substances, so I had put this idea on the back burner until last year when I was invited by Edison and the Uniao do Vegetal to attend a conference in Brazil that they organized to give a paper on my chemical and pharmacological work on hoasca. I realized when I was there that the membership of the Uniao could provide an ideal group to study. Many of them were urban professional people who could be monitored and interviewed and could have medical tests performed with their full consent, and who would understand the value of the research. I broached the idea to Edison and some of his colleagues, and I was a little apprehensive because they regard hoasca as a sacrament, so I was worried they might feel I was being blasphemous in some way, but I found in them an extreme attitude of openness and a desire to understand their sacrament on all levels from the biophysical to the metaphysical. They were enthusiastically receptive to the idea.

So we began working together and I thought I would come back to the U.S. and write a grant and submit it to NIDA, the National Institute on Drug Abuse-the government agency that funds these kinds of studies. I started to write the grant. I worked on it for a year or so, and as I was working on one of the final drafts, I was reading it through and I realized that NIDA would never go for it. I realized that the only chance to fund such a project was to find some private individuals with resources whose lives had been touched by shamanic plants who would be willing to fund this sort of research, and lo and behold a couple of very generous individuals, one of whom is Jeffrey Bronfman, came forward. We picked Dr. Charles Grob from UC Irvine Medical School to act as the principle medical investigator, and we are now ready to initiate a pilot study on the biomedical effects of ayahuasca in people who have used it for many, many years.

Charles Grob, MD: I’m a psychiatrist at UC Irvine. I have had a long-standing interest in the potential medical and psychiatric application of psychedelic drugs. In fact, that is a good part of the reason why I decided twenty years ago to go to medical school. I felt that in order to do that sort of research, I had to get unimpeachable credentials. When I made that decision to go to med school twenty years ago, I figured that in about five years the country would come to its senses and we would be allowed to do sanctioned research the way it should be done, but here we are, twenty years later, and we are barely now on the verge of perhaps being able to resume some serious research on psychedelic substances.

Most people don’t realize that some 35 years ago psychedelic drugs were one of the hottest topics of study within psychiatry. It was widely felt at the time that they might hold an important key to really understanding how the mind works, to understanding psychopathology and to developing new treatments that could help people overcome some mental afflictions and live healthier, more fulfilling lives. I think that potential is still there. Tragically this research was blocked twenty years ago and it has not been allowed to go forth, but I think that is starting to change, though still very slowly and hesitatingly. I had submitted a protocol to do a study on MDMA, which may have considerable therapeutic potential. After a long series of drafts of a protocol, we submitted a proposal to the FDA and the decision there was very encouraging. They essentially felt that this was a worthy area of study and basically should be treated no differently than any other drug. Perhaps we are starting to see a slight paradigm shift, so I was very excited when Dennis asked me if I wished to join him as a co-investigator on the Hoasca Project. Ayahuasca has been used as a medicinal remedy and shamanic plant for thousands of years. It has enormous potential. Our study is essentially designed to look at both the physiology of experienced users when they imbibe the substance and at the biochemistry, particularly as it relates to neurotransmitter function and psychological effects. It is our hope that with the preliminary data that we can gather with our initial trip and work in Brazil that we might be in a better position to approach our own government, NIDA or other government agencies, to approve and support further research here.

Andrew Weil, MD: I am from the University of Arizona College of Medicine. I am a botanist and practicing physician. I practice natural and preventive medicine. My main interest has always been teaching people correct uses of plants and the most profitable uses of plants, and I include shamanic plants in that. I’ve always been interested in the healing potentials of the psychedelic plants and drugs, not just in psychiatric medicine, which is what most of the literature has been about, but in clinical medicine as well, because I have seen remarkable examples of healings from chronic pain syndromes in autoimmune disorders in connection with psychedelic experiences, and I think it’s a shame that physicians are denied the right to experiment with and use those drugs clinically, especially since from a medical viewpoint most of these are among the safest of all known drugs in terms of toxicity. Most of the things that we routinely dispense to patients are much, much more toxic than the true psychedelics.

I am also interested in magical plants other than psychedelics, and an example of one that I have had a long history of involvement with is coca leaf. I think the history of coca is the most flagrant example of the way in which we have gone wrong in our relationships with plants. Coca is the sacred plant of a large population of Native Americans in the Andes. The religious and sacramental significance of coca is enormous in these cultures. If you are in the area where coca is used and watch Indians in an unobtrusive way, you will often see them when they first begin to chew coca take three perfect leaves and put them together in their hand and then blow on them and whisper a prayer to the leaves before they put them in their mouths. There is a tradition of divination involving reading coca leaves in the Andean highlands, done mostly by women. You cannot get the power to read coca leaves in this way, they say, until you have been struck by lightning and survived. These are just a few examples of how central to the spiritual life of Andean culture coca is.

When the Spanish Conquistadores came to the New World, their immediate reaction to coca (and to most everything else associated with Indian life) was that it was satanic and should be suppressed. They tried to do that initially, but then they discovered that Indians worked better if they gave them coca. They enslaved a lot of the Indians and put them to work in mines and found that selling coca to them and profiting from the sale of it as well as getting enhanced labor was in their own selfish interest, so for the next couple of centuries, the only interest that Westerners had in coca was that it was a tool to get more work out of Indians. It wasn’t until about 1869 or 1870 when an Italian neurologist wrote an essay about coca, pointing out that it had very unusual, interesting properties that Europeans got interested in it. Within a year of that, cocaine was isolated from coca, and all scientific interest shifted to cocaine in the belief that all of the active properties of coca leaf were to be found therein in a form far easier to measure and study that in the whole plant. We are paying dearly for that reductionistic mistake to this day. It has led to an epidemic of cocaine use in the world created entirely, initially, by the medical profession, which handed it out as a panacea thinking that it had no downside. Eventually the problems caused by its abuse led to a great public outcry against cocaine, and the medical profession then had the same response it has had for a century or so to every psychoactive drug that it has initially mis-prescribed: it deflected any blame for its prescribing practices and labeled coca an inherently bad substance with no redeeming qualities. When you do this and a drug is banned, instantly a black market comes into existence to supply the thousands of people who have been addicted to it by doctors.

The laws against cocaine drove out of circulation the safe form of that plant, the leaves, which have medicinal properties and are not very prone to abuse as they have low addictive potential, and they created an enormous black market in cocaine. Massive efforts are made to eradicate the plant in the area where it grows, so there has been a constant, bloody, destructive war against coca growers (and the ecosystems in which they live) in the Andes stimulated by the international narcotics control bodies, with the U.S. at the helm. Clearly, this war suppresses Indian peoples. The chewing of coca is a very powerful symbol of Indian identity in these regions, so the people who want coca to go away really want Indians to go away, or they want Indians to turn into us, though the rationale is always posited in medical, psychiatric Terms.

The quality of scientific research on coca’s supposed harm in the Andean areas has been dismal. To cite only one example, in the late ‘60s, the United Nations sent a team of Canadian psychologists into Andean villages to administer standard Western intelligence-scale tests to Indians to “measure” their intelligence. They somehow concluded from the results of this culturally absurd, racist exercise in bad science that coca caused mental deterioration and brain damage, and this was then used as a further rationale to step up the war against the coca leaf. The shame of it is that coca leaf has a whole range of interesting therapeutic qualities not attributable to cocaine alone but to a wide range of chemicals found in the whole plant. You lose positive aspects of the plant in transforming it into cocaine. I think of all the many cases I have looked at of magical plants and relationships that people have formed with them, I have never seen one in which it is so obvious what our culture has done wrong, and the scale on which the mistake has been made and the costs of it, both to us and to the native populations that originally knew how to use this leaf, are just flagrant and horrible and tragic. It would be wonderful if we could shift that.

Marcellus Bear Heart Williams: I have an adopted son named Johnny White Cloud who couldn’t be here today and asked me to come to say something about the Native American church and peyote. So far chemists have found more than 59 different alkaloids in peyote. It has very complex kinesthetic, olfactory, visual and auditory properties. There is a long history of pre-Christian use of peyote. It came to the United States from Mexico, and Indians in the Southwest began using it centuries ago, but not in an organized church context. Different people began to investigate its use in the late 19 th and early 20 th centuries because white settlers who thought Indians were pretty crazy to begin with were really worried about those crazy Indians getting even more loco by eating that loco stuff.

Early in the 20th century, James Mooney, the historian, was taken into some of the peyote meetings. He advised the Indians that they had something really good going on. He told them: “If you want to protect your peyote ceremony, charter yourselves as a church, because before too long the BIA (Bureau of Indian Affairs, but we say BIA stands for “bossing Indians around”) will try to stamp it out, and not only that, but missionaries will also come and try to stamp it out.” The Indians took his advice. On October 10, 1918, at my Uncle Bob Cook’s place in Oklahoma, the Native American Church was chartered.

We had used this peyote long before then, and many of the old timers who have kept traditional ways still address the supreme being by the same name that they used before white men came to this continent, but one of the main leaders who helped found that church back in 1918 had become Christianized into the Methodist faith, and he said we should keep our Indian motifs, the teepee and our traditional paraphernalia in our ceremonies, but that he had been fasting and praying and eating peyote and drinking peyote tea and he had received guiding visions about the structure of the church. It would be called the Native American church and it would also incorporate Christian teachings. Because he was a respected leader, people went along with his vision.

In this church many miraculous things have happened over the years. A lot of psychological and spiritual power seems to evolve within a circle as we do our ceremonies, and people have been cured of serious illnesses. Many, many people have straightened out their lives and stopped drinking. It is not the peyote itself. The peyote is only used as a focal point for the power of the creator. We don’t worship this herb. We acknowledge it as a gift from the creator through which we manifest many positive forces that can help us heal emotional, physical or spiritual illness.

Florencio Siquera de Carvalho: I am a very simple person. I have lived most of my life in the forest. I have learned a lesson that has been very important for me: I know that I don’t know anything. I am a member of the Uniao do Vegetal and I hold it and all its members very dear to my heart. I have been drinking ayahuasca tea for more than thirty years. I leave it up to your criteria, you who are well studied and knowledgeable about many things, to judge whether this tea has or hasn’t been beneficial for me. We use this tea for mental concentration and to cure illnesses of all types. One of the illnesses that the vegetal has cured the most is the fighting amongst neighbors. It has brought people to join their hands together to be friends and brothers. For this reason, I am proud to be a member of this sacred organization, the Uniao do Vegetal, and I don’t consider this particular pride to be a human fault.

Audience Questions and Panelists’ Responses:

Q: How might we use these plants therapeutically outside of a traditional ritual context?

Andrew Weil: One of the problems that happened with early LSD research was that researchers who took LSD themselves and had positive experiences with it and understood its potential to alter consciousness in ways that could serve healing, conducted studies and published their results, but then other people who had never taken LSD and didn’t understand the way it worked and thought of it as a magic bullet went about administering it in other circumstances without attention to set and setting and didn’t get the same positive results. That kind of controversy in the literature, I think, scared a lot of other researchers away from attempting to use LSD therapeutically. The point is that these drugs in themselves don’t have absolute properties. They can have certain positive therapeutic properties if they are used in the right context and if the expectation of both the patient and the doctor are supportive. That is difficult at the moment to explain to many physicians and many psychiatrists who think that the magic is all in the substance. It’s a matter of training people to use these things correctly. The first prerequisite is having the experience yourself and in the right sort of context so that you can transmit it to other people. There’s no substitute for that.

Q: I was wondering if anyone who’s involved with the Hoasca Project has thought of the idea of using it as a possible therapeutic tool to help rehabilitate prisoners and criminals.

Dennis McKenna: Certainly part of the objective of the project, which is a long-term process, is to look at many potential therapeutic uses. I think it would be great if you could use it to treat, for example, chemical dependency. I think it might have great possibilities in that realm, but the initial objectives of the project are more modest than that. Basically nothing is known about the pharmacology of ayahuasca. We are trying to get some baseline data, some limited amount of information about how it acts on human physiology and on human cognitive functions. Once we have that, hopefully, out of that will emerge some suggestions, some ideas as to where to go. In other words, the data sort of defines itself. The way that science works is that you do experiments, you get results, you look at the results and then you try to ascertain what the next logical question to be answered is. But because of the political and regulatory climate in this country we are a long way from being able to use ayahuasca or any other traditional consciousness altering substances in that sort of human research here, especially in prisons. That doesn’t mean that that sort of thing can’t be pursued in Brazil where religious ayahuasca use is now legally recognized or in other countries where there is more openness to such research.

Marcellus Bear Heart Williams: We in the Native American Church really have to hurdle the FDA to get peyote in to our church members who are in prisons, but our ceremonies have helped reform quite a few criminals. I’ll give you an example. Roland Hague was a notorious troublemaker who did drugs, stole cars, robbed banks and went to prison. Even his mother had given up on him. But when he came out, somebody brought him to the church, and he never went back to drugs or crime. He is now a very respected member of the Cheyenne tribe. There is no doubt that it can turn things around.

Dr. Edison Saraiva: In Brazil we are already working all the time with ex-prisoners among our members in the Uniao, getting excellent results with their rehabilitation and social re-integration, and we would like to be able in the near future to also work with prisoners while they are still behind bars.

Q: I’m wondering what you think will happen with the use of ayahuasca analogues in North America. I’ve heard people have discovered high amounts of DMT (editor’s note: dimethyltryptamine-the most active hallucinogen in the ayahuasca brew) and harmaline (the other main chemical component of the tea) in a variety of plants that are indigenous to our region.

Kathleen Harrison: It’s true that upon hearing about ayahuasca in the last decade or so a number of inquisitive North Americans have looked into what might be here in our territory that would have the same components. There is a lot of searching and experimentation going on with several plant species. I think some of the amounts of active components that have been reported are exaggerated, but people could probably come up with a contemporary North American botanical analogue to ayahuasca, and what would happen with it would really depend, as always, with the attitude people prepared it with and how they approached the experience. Such people would be wise to model their use on the indigenous traditions that have a long history of using these substances to build respectful, reciprocal relationships and to achieve healing on many levels. That’s the reason that I have spent so many years studying these cultures and traveling to experience the way that different indigenous people use their shamanic plants. If we use these sacred plants, we have to do it right.

Panel Biographies

Marcellus Bear Heart Williams, (1918-2008), born in Okemah, Oklahoma, was a full-blood spiritual leader of the Muskogee-Creek Nation trained in the traditional ways of his tribe. Highly regarded as a healer and counselor, he was also a respected leader of the Native American Church, Sun Danced with both the Northern and Southern Cheyenne people, and was an ordained minister in the American Baptist Church. Bear Heart was asked to be one of the spiritual counselors for the firemen and their families after the Oklahoma City bombing tragedy and put down prayers with the Fire Department at Ground Zero, New York in November, 2001. Bear Heart helped thousands of people over the course of his life and his book and is the author of The Wind Is My Mother.

Charles S. Grob, M.D., a professor of Psychiatry and Bio-behavioral Sciences and Pediatrics at the UCLA School of Medicine and Director of the Division of Child and Adolescent Psychiatry at Harbor-UCLA Medical Center, conducted the first government-approved study of MDMA, and was the principal investigator of an international biomedical psychiatric research project in the Brazilian Amazon of the plant, ayahuasca. He has also conducted investigations into the effects of psilocybin on anxiety in terminal cancer patients. Dr. Grob has published numerous articles in medical and psychiatric journals and collected volumes, and is the editor of Hallucinogens: A Reader. He is a founding board member of the Heffter Research Institute.

Kathleen (Kat) Harrison is an ethnobotanist, artist, illustrator, and photographer who researches the relationship between plants and people, with a particular focus on art, myth, ritual, and spirituality. Kathleen has taught at the California School of Herbal Studies, Sonoma State University, and the University of Minnesota (with field courses in Hawaii), and has done fieldwork in Latin America for several decades. She is the co-founder and Director of Botanical Dimensions in Occidental, CA (, a nonprofit foundation whose aim is to preserve plant knowledge as it pertains to medicinal and shamanic usage. Kat Harrison’s is a unique voice in ethnobotany. She brings deep integrity and fearlessness and a lovingly intense, profound intelligence to the study of medicinal and sacred plants and human cultures.

Dennis McKenna, Ph.D., is a renowned ethnopharmacologist who co-authored, with his brother Terence, a classic in the field of psychedelic literature, The Invisible Landscape, which recounted their wild adventures in pursuit of Amazonian hallucinogens in 1971. He co-stars in Terence’s later book, True Hallucinations, which further describes that fateful trip. Dennis earned his Master’s degree in botany at the University of Hawaii in 1979 and his Doctorate in botanical sciences in 1984 from the University of British Columbia. In the early 1990s he held positions at Shaman Pharmaceuticals (Director of Ethnopharmacology) and the Aveda Corporation (Senior Research Pharmacognosist). In 1998 Dennis co-founded the non-profit Institute for Natural Products Research (INPR) to promote research and scientific education with respect to botanical medicines and other natural medicines. Dennis is also a founding board member of the Heffter Research Institute and serves on the advisory board of the American Botanical Council. He has served as a board member for Botanical Dimensions and as well, he is the editor-in-chief of The Natural Dietary Supplements Pocket Reference and Botanical Medicines: The Desk Reference for Major Herbal Supplements and the author of countless scientific papers. From 2004-2008, he was Principal Investigator on a project to investigate Amazonian ethnomedicnes as potential treatments for cognitive deficits in dementias and schizophrenia funded by the Stanley Medical Research Institute. In 2010, he served as co-Principal Investigator for the Botanical Dimensions/UNAP Digital Herbarium Project, a three-year project to scan and digitize the 100,000+ specimens in the AMAZ Herbarium at the Universidad Nacional de la Amazonía Peruana (UNAP) in Iquitos, Peru. His most recent book was a memoir: The Brotherhood of the Screaming Abyss: My Life with Terence McKenna.

Edison Saraiva, MD., a Brazilian physician and homeopathic doctor and a specialist in eco-toxicology and nutrition who worked with the Brazilian Ministry of the Interior in the northwest Amazon for many years, is a long time member of the Uniao do Vegetal church which uses ayahuasca as a sacrament.

Florencio Siquera de Carvalho, now deceased, a humble man with very little formal education who endured intense poverty and suffering in his life, most of it lived in the Amazon jungle, became an important spiritual teacher in Brazil’s Uniao do Vegetal church, which uses hoasca (ayahuasca) as a sacrament.

Andrew Weil, M.D., trained at Harvard Medical School, was already well known in 1992, but he subsequently became the most famous pioneer of holistic/integrative medicine on the planet. He has impeccable mainstream medical credentials, but he also has a Harvard degree in botany, and, like Wade Davis, was a student of the amazing pioneer in Ethnobotany, Richard Evans Schultes. He worked for 13 years on the research staff of the Harvard Botanical Museum and traveled extensively throughout the Americas and Africa in the 1970s studying indigenous and folk medical healing traditions. He has become famous with books on natural medicine such as Natural Health, Natural Medicine; Spontaneous Healing; Eight Weeks to Optimum Health; and Eating Well for Optimum Health, but he has also long been one of the sanest voices on drug use in our culture in controversial books such as The Natural Mind and From Chocolate to Morphine. Dr. Weil went on to found and direct the Andrew Weil Center for Integrative Medicine at the University of Arizona, where he also holds the Lovell-Jones Endowed Chair in Integrative Rheumatology, and is Clinical Professor of Medicine and Professor of Public Health. The Center is the leading effort in the world to develop a comprehensive curriculum in integrative medicine. Graduates of that program now serve as directors of integrative medicine programs throughout the United States, and through its fellowship, the Center is now training doctors and nurse practitioners around the world.

A version of this presentation appeared in Visionary Plant Consciousness Edited by J.P. Harpignies, published by Inner Traditions International and Bear & Company, ©2007. All rights reserved.  Reprinted with permission of publisher.

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