In this episode of Plants of the Gods, ethnobotanist Dr. Mark Plotkin takes us on a sweeping journey through the epic history of the spice trade—one of the most transformative chapters in global history. From ancient trade routes and religious rituals to colonial conquests and modern capitalism, spices like cinnamon, pepper, nutmeg, and cloves have shaped agriculture, medicine, navigation, and even warfare. Dr. Plotkin also reviews Roger Crowley’s gripping new book, Spice: The 16th-Century Contest That Shaped the Modern World.

The Plants of the Gods podcast has pioneered the concept of mind-altering substances not being merely hallucinogens but also "ideogens," substances that generate new ideas and creative concepts. Nowhere was this more evident than among artists and the scientists in 19th-century Europe, from Sigmund Freud to Samuel Taylor Coleridge to William James. This episode details this much-overlooked chapter in modern history and discusses a recent book by cultural historian Mike Jay on this topic.

Ethnobotanist Dr. Mark Plotkin discusses Brugmansia, some of the most beautiful hallucinogenic plants in the botanical world. Their bright flowers hang like sacred trumpets and have long been used by traditional healers of the Andes-Amazon region as an important component of their medicine chest. Closely related to the ‘hexing herbs’ of European witches of the Middle Ages (as detailed in an earlier episode), these fascinating plants can heal - or harm.

The spice trade was one of the most influential economic and cultural forces that shaped the modern world. It profoundly impacted cultural exchange, cartographic knowledge and technology, cuisine, spycraft, and medicine. The spice trade strengthened mercantile capitalism and spread both Islam and Christianity while destroying indigenous cultures and tropical rainforests. This episode examines the spice trade from an ethnobotanical perspective.

Hobhouse, Henry. Seeds of Wealth: Four Plants That Made Men Rich. 1st Shoemaker & Hoard ed., Shoemaker & Hoard, 2004.

Levetin, Estelle, and Karen McMahon. Plants & Society. Ninth edition, McGraw-Hill LLC, 2024.

Miller, James Innes. The Spice Trade of the Roman Empire, 29 B.C. to A.D. 641. Clarendon P, 1969.

Milton, Giles. Nathaniel’s Nutmeg: How One Man’s Courage Changed the Course of History. Sceptre, 1999.

Norman, Jill. The Complete Book of Spices. First American edition., Viking Studio Books, 1991.

Rosengarten, Frederic. The Book of Spices. Rev. and Abridged by the author., Pyramid Books, 1973.

Schivelbusch, Wolfgang, and Wolfgang Schivelbusch. Tastes of Paradise: A Social History of Spices, Stimulants, and Intoxicants. 1st Vintage Books ed, Vintage Books, 1993.

Simpson, Beryl Brintnall, and Molly Conner-Ogorzaly. Economic Botany: Plants in Our World. 3rd ed, McGraw-Hill, 2001.

Tannahill, Reay. Food in History. New ed., Three Rivers Press, 1989.

If herbal remedies can help humans, why not our pets? In this fascinating episode of Plants of the Gods, ethnobotanist Dr. Mark Plotkin sits down with veterinarian Dr. Rob Silver, who has spent decades using cannabis, mushrooms, and other botanical medicines to treat animals. From clinical breakthroughs to the surprising science behind plant-based pet care, Dr. Silver shares stories from the front lines of integrative veterinary medicine—and introduces his new book, There’s a Mushroom for That!. Whether you’re a pet lover or a mycology fan, this conversation will change the way you think about both.

Show notes:

The K9 Microdose Project landing page for dog owners interested in a study on mushroom supplementation for their pet: K9Microdose.com

There’s A Mushroom For That!: https://www.amazon.com/dp/B0DJG1M348

Dr. Robert Silver’s apothecary shop for pets: www.wellpetdispensary.com

“Plants of the Gods” has featured dozens of episodes detailing the power, potential, and pitfalls of using hallucinogenic plants and fungi – and even frogs – for healing purposes. The Psychedelic Renaissance is in full swing — but what does it look like to the indigenous peoples themselves?

Anthropologist Dr. Joe Watkins of the Choctaw Nation offers his thoughtful perspective on these fascinating issues.

A mind-blowing mint? Salvia divinorum, a perennial herb in the mint family, has been used by traditional healers in Oaxaca, Mexico, to understand more about what ails a patient. Known for its potent psychoactive effects, Salvia can induce dysphoria and dissociation. But new scientific research is shedding light on the plant's unique effect on the brain, and its potential in treating psychiatric disorders. We continue our conversation with Dr. Chris McCurdy, a medicinal chemist and behavioral pharmacologist at the University of Florida, who is one of the foremost experts on this plant of the gods.

Show notes:

Babu, Kavita M, et al. “Opioid Receptors and Legal Highs: Salvia Divinorum and Kratom.” National Center for Biotechnology Information, U.S. National Library of Medicine, Feb. 2008, pubmed.ncbi.nlm.nih.gov/18259963/.

The tropical Asian tree kratom – a member of the same botanical family that has given us both coffee and quinine – is showing great potential for successfully treating a variety of serious afflictions, from stress to opioid withdrawal. Ironically – depending on dosage – it can act either as a stimulant or a sedative. The episode features an insightful interview with Dr. Christopher McCurdy, the leading authority on this extraordinary plant of the gods.

Show notes:

“About Christopher R McCurdy.” University of Florida College of Pharmacy, pharmacy.ufl.edu/profile/mccurdy-christopher/. Accessed 17 June 2025.

Grundmann, Oliver, et al. “Not All Kratom Is Equal: The Important Distinction between Native Leaf and Extract Products - Grundmann - 2024 - Addiction - Wiley Online Library.” Wiley Online Library, 9 Oct. 2023, onlinelibrary.wiley.com/doi/10.1111/add.16366.

Smith, Kirsten E., et al. “The Rise of Novel, Semi-Synthetic 7-Hydroxymitragynine Products.” Wiley Online Library, 3 Dec. 2024, onlinelibrary.wiley.com/doi/10.1111/add.16728.

Talesnik, Dana. “McCurdy Studies Whether Kratom Can Reduce Opioid Withdrawal, Ease Pain.” National Institutes of Health, U.S. Department of Health and Human Services, 23 June 2022, nihrecord.nih.gov/2022/06/24/mccurdy-studies-whether-kratom-can-reduce-opioid-withdrawal-ease-pain.