by Amy Stewart
WICKED PLANTS
ALSO BY AMY STEWART
From the Ground Up: The Story of a First Garden
The Earth Moved: On the Remarkable
Achievements of Earthworms
Flower Confidential: The Good, the Bad,
and the Beautiful in the Business of Flowers
Wicked Plants
THE WEED THAT KILLED LINCOLN’S MOTHER & OTHER BOTANICAL ATROCITIES
Amy Stewart
ETCHINGS BY BRIONY MORROW-CRIBBS
ILLUSTRATIONS BY JONATHON ROSEN
Published by
ALGONQUIN BOOKS OF CHAPEL HILL
Post Office Box 2225
Chapel Hill, North Carolina 27515-2225
a division of
WORKMAN PUBLISHING
225 Varick Street
New York, New York 10014
© 2009 by Amy Stewart. All rights reserved.
Printed in the United States of America.
Published simultaneously in Canada by Thomas Allen & Son Limited.
Design by Anne Winslow, with thanks to Jean-Marc Troadec.
Library of Congress Cataloging-in-Publication Data
Stewart, Amy.
Wicked plants : the weed that killed Lincoln’s mother and other botanical atrocities / by Amy Stewart; with etchings by Briony Morrow-Cribbs and illustrations by Jonathon Rosen.—1st ed.
p. cm.
Includes bibliographical references.
ISBN-13: 978-1-56512-683-1
1. Poisonous plants. 2. Dangerous plants. I. Morrow-Cribbs, Briony.
II. Rosen, Jonathon. III. Title.
QK100.A1S74 2009
581.6’5—dc22 2009006192
10 9 8 7 6 5 4 3 2
To PSB
Would not the earth, quickened to an evil purpose by the sympathy of his eye, greet him with poisonous shrubs . . . Would he not suddenly sink into the earth, leaving a barren and blasted spot, where, in due course of time, would be seen deadly nightshade, dogwood, henbane, and whatever else of vegetable wickedness the climate could produce, all flourishing with hideous luxuriance?
—Nathaniel Hawthorne, The Scarlet Letter
CONTENTS
Consider Yourself Warned
Aconite
Arrow Poisons
Ayahuasca Vine and Chacruna
Betel Nut
Castor Bean
Ordeal Poisons
Coca
Coyotillo
This Houseplant Could Be Your Last
Deadly Nightshade
Death Camas
Deadly Dinner
Ergot
Fatal Fungus
Habanero Chili
Henbane
The Devil’s Bartender
Iboga
Jimson Weed
Botanical Crime Families
Khat
Killer Algae
Stop and Smell the Ragweed
Kudzu
Lawn of Death
Mala Mujer
Here Comes the Sun
Manchineel Tree
Don’t Look Now
Mandrake
Marijuana
Oleander
Forbidden Garden
Opium Poppy
Dreadful Bouquet
Peacock Flower
Peyote Cactus
Psychedelic Plants
Poison Hemlock
Purple Loosetrife
Weeds of Mass Destruction
Ratbane
Rosary Pea
The Terrible Toxicodendrons
Sago Palm
More Than One Way to Skin a Cat
Stinging Tree
Meet the Nettles
Strychnine Tree
Suicide Tree
Carnivores
Tobacco
Toxic Blue-Green Algae
Duck and Cover
Water Hemlock
Water Hyacinth
Social Misfists
Whistling Thorn Acacia
Guess Who’s Coming to Dinner
White Snakeroot
Don’t Tread on Me
Yew
END NOTES
Antidote
About the Artists
Poison Gardens
Bibliography
INTRODUCTION
Consider Yourself Warned
A tree sheds poison daggers; a glistening red seed stops the heart; a shrub causes intolerable pain; a vine intoxicates; a leaf triggers a war. Within the plant kingdom lurk unfathomable evils.
In his 1844 story “Rappaccini’s Daughter,” Nathaniel Hawthorne described an elderly doctor who tended a mysterious walled garden of poisonous plants. The old man’s demeanor in the presence of his shrubs and vines “was that of one walking among malignant influences, such as savage beasts, or deadly snakes, or evil spirits, which, should he allow them one moment of license, would wreak upon him some terrible fatality.” The story’s hero, young Giovanni, watched from a window and found it most disturbing “to see this air of insecurity in a person cultivating a garden, that most simple and innocent of human toils.”
Innocent? This is how Giovanni viewed the luxuriant vegetation below his window, and it is how most of us approach our gardens and the plants we encounter in the wild: with a kind of naïve trust. We would never pick up a discarded coffee cup from the sidewalk and drink from it, but on a hike we’ll nibble unfamiliar berries as if they had been placed there for our appetites alone. We’ll brew a medicinal tea from unrecognizable bark and leaves that a friend passes along, assuming that anything natural must be safe. And when a baby comes home, we rush to add safety caps to electrical outlets but ignore the houseplant in the kitchen and the shrub by the front door—this in spite of the fact that 3,900 people are injured annually by electrical outlets while 68,847 are poisoned by plants.
You can garden for years without ever suffering the ill effects of a plant like monkshood, whose cheerful blue flowers conceal a toxin that brings on death by asphyxiation. You can hike for miles and never encounter the coyotillo shrub, whose berries cause a slow but deadly paralysis. But someday the plant kingdom’s dark side may make itself known to you. When it does, you should be prepared.
I DIDN’T WRITE this book to scare people away from the outdoors. Quite the opposite is true. I think that we all benefit from spending more time in nature—but we should also understand its power. I live on the rugged northern California coast, and every summer the Pacific Ocean sneaks up behind a family enjoying a day at the beach and claims a life. Those of us who live here know that so-called sleeper waves can kill with no warning. I love the ocean, but I never turn my back on it. Plants deserve the same kind of guarded respect. They can nourish and heal, but they can also destroy.
Some of the plants in this book have quite a scandalous history. A weed killed Abraham Lincoln’s mother. A shrub nearly blinded Frederick Law Olmsted, America’s most famous landscape architect. A flowering bulb sickened members of the Lewis and Clark expedition. Poison hemlock killed Socrates, and the most wicked weed of all—tobacco—has claimed ninety million lives. A stimulating little bush in Colombia and Bolivia called Erythroxylum coca has fueled a global drug war, and hellebore was used by the ancient Greeks in one of the earliest instances of chemical warfare.
Plants that are monstrously ill mannered deserve recognition, too: kudzu has devoured cars and buildings in the American South, and a seaweed known as killer algae escaped from Jacques Cousteau’s aquarium in Monaco and continues to smother ocean floors around the world. The horrid corpse flower reeks of dead bodies; the carnivorous Nepenthes truncata can devour a mouse; and the whistling thorn acacia harbors an army of aggressive ants that attack anyone who comes near the tree. Even a few interlopers from outside the plant kingdom—hallucinogen
ic mushrooms, toxic algae—merit inclusion here for their wicked ways.
If this book entertains, alarms, and enlightens you, I’ve done my job. I’m not a botanist or a scientist but rather a writer and a gardener who is fascinated by the natural world. These are the most fascinating and evil plants from among thousands that grow around the world. If you’re in the market for a comprehensive poisonous plant identification guide, I’ve included a special section for you in the bibliography. And if you suspect that someone has been poisoned by a plant, please do not spend precious time flipping through this book in search of symptoms or a diagnosis. While I describe the possible or probable effects of many toxins, their potency can vary widely depending on the plant’s size, the time of day, the temperature, the part of the plant in question, and how it was ingested. Don’t try to figure it out on your own. Instead, call a poison control center at (800) 222-1222, or seek immediate medical attention.
Finally, do not experiment with unfamiliar plants or take a plant’s power lightly. Wear gloves in the garden; think twice before swallowing a berry on the trail or throwing a root into the stew pot. If you have small children, teach them not to put plants in their mouths. If you have pets, remove the temptation of poisonous plants from their environment. The nursery industry is woefully lax about identifying poisonous plants; let your garden center know that you’d like to see sensible, accurate labeling of plants that could harm you. Use reliable sources to identify poisonous, medicinal, and edible plants. (A great deal of misinformation circulates on the Internet, with tragic consequences.) I did not shy away from including plants that intoxicate, but I included them to provide a warning, not an endorsement.
I CONFESS THAT I am enchanted by the plant kingdom’s criminal element. I love a good villain, whether it is an enormous specimen of Euphorbia tirucalli, the pencil cactus with corrosive sap that raises welts on the skin, on display at a garden show, or the hallucinatory moonflower, Datura inoxia, blooming in the desert. There is something beguiling about sharing their dark little secrets. And these secrets don’t just lurk in a remote jungle. They’re in our own backyards.
WICKED PLANTS
DEADLY
Aconite
ACONITUM NAPELLUS
In 1856 a dinner party in the Scottish village of Ding-wall came to a horrible end. A servant had been sent outside to dig up horseradish, but instead he uprooted aconite, also called monkshood. The cook, failing to recognize that she had been handed the wrong ingredient, grated it into a sauce for the roast and promptly killed two priests who were guests at the dinner. Other guests were sickened but survived.
FAMILY:
Ranunculaceae
HABITAT:
Rich, moist garden soil, temperate climates
NATIVE TO:
Europe
COMMON NAMES:
Wolfsbane, monkshood, leopard’s bane
Even today, aconite is easily mistaken for an edible herb. This sturdy, low-growing herbaceous perennial is found in gardens and in the wild throughout Europe and the United States. The spikes of blue flowers give the plant its common name “monkshood” because the uppermost sepal is shaped like a helmet or a hood. All parts of the plant are extremely toxic. Gardeners should wear gloves anytime they go near it, and backpackers should not be tempted by its white, carrot-shaped root. The Canadian actor Andre Noble died of aconite poisoning after he encountered it on a hiking trip in 2004.
The poison, an alkaloid called aconitine, paralyzes the nerves, lowers the blood pressure, and eventually stops the heart. (Alkaloids are organic compounds that in many cases have some kind of pharmacological effect on humans or animals.) Swallowing the plant or its roots can bring on severe vomiting and then death by asphyxiation. Even casual skin contact can cause numbness, tingling, and cardiac symptoms. Aconitine is so powerful that Nazi scientists found it useful as an ingredient for poisoned bullets.
Nazi scientists found aconite useful as an ingredient for poisoned bullets.
In Greek mythology, deadly aconite sprang from the spit of the three-headed hound Cerberus as Hercules dragged it out of Hades. Legend has it that it got another of its common names, wolfsbane, because ancient Greek hunters used it as a bait and arrow poison to hunt wolves. Its reputation as a witch’s potion from the Middle Ages earned it a starring role in the Harry Potter series, where Professor Snape brews it to assist Remus Lupin in his transformation to a werewolf.
Meet the Relatives Related to aconite are the lovely blue and white Aconitum cammarum; the delphinium-like A. carmichaelii; and the yellow A. lycoctonum, commonly referred to as wolfsbane.
DEADLY
ARROW POISONS
Indigenous tribes in South America and Africa have used toxic plants as arrow poisons for centuries. The poisonous sap of a tropical vine, rubbed onto an arrowhead, makes a potent tool for both warriors and hunters. Many arrow poisons, including the tropical vine curare, cause paralysis. The lungs stop working, and eventually the heart stops beating, but there are often no outward signs of agony.
CURARE
Chondrodendron tomentosum
A sturdy, woody vine found throughout South America. It contains a powerful alkaloid called d-tubocurarine that acts as a muscle relaxant. Useful for hunters, it rapidly immobilizes prey, even causing birds to fall from the trees. Any game caught using arrows poisoned with curare would be safe to eat, because the toxin is only effective when it enters the bloodstream directly, as opposed to the digestive tract.
If the animal (or enemy) is not slaughtered right away, death comes within a few hours as paralysis reaches the respiratory system. Experiments on animals poisoned in this manner have shown that once breathing stops, the heart continues to beat for a short time, even though the poor creature appears dead.
The power of this drug was not lost on nineteenth- and twentieth-century physicians, who realized that it could be used to hold a patient still during surgery. Unfortunately, it did nothing to relieve the pain, but it would allow a doctor to go about his work without the distraction of a patient’s thrashing about. As long as artificial respiration was maintained throughout the surgery to keep the lungs functioning, the curare would eventually wear off and leave no long-lasting side effects. In fact, an extract from the plant was used in combination with other anesthesia throughout most of the twentieth century, but new, improved drugs have taken its place.
The word curare has also been used to refer more generally to a wide variety of arrow poisons derived from plants, including:
STRYCHNINE VINE
Strychnos toxifera
A South American vine closely related to the strychnine tree, Strychnos nux-vomica. Like curare, it causes paralysis. In fact, the two were often used in combination.
KOMBE
Strophanthus kombe
A native African vine containing a cardiac glycoside that goes directly to work on the heart. While a powerful dose may stop the heart, extracts have also been used as a cardiac stimulant to treat heart failure or irregular heartbeats. Nineteenth-century plant explorer Sir John Kirk obtained specimens of the plant to bring back to the Royal Botanic Garden at Kew and inadvertently participated in a medical experiment: he accidentally got a little juice from the plant on his toothbrush and reported a quick drop in his pulse rate after he brushed his teeth.
UPAS TREE
Antiaris toxicaria
A member of the mulberry family native to China and other parts of Asia. The bark and leaves produce a highly toxic sap. Charles Darwin’s grandfather Erasmus claimed that the tree’s fumes could kill anyone who went within miles of it. Although this is only legend, references to the noxious fumes of the upas tree can be found in the writings of Charles Dickens, Lord Bryon, and Charlotte Brontë. A character in a Dorothy L. Sayers novel once described a serial killer as “first cousin to an upas tree.” Like other arrow poisons, the sap contains a powerful alkaloid that can stop the heart.
Charles Darwin’s grandfather Erasmus claimed that the upas tree’s
fumes could kill anyone who went within miles of it.
POISON ARROW PLANT
Acokanthera spp.
An appropriately named shrub native to South Africa that also kills by attacking the heart. Some reports show that it was used in a particularly devious way: the juice was smeared on the sharp seeds of puncture vine (Tribulus terrestris). The seeds grow in the sturdy shape of a caltrop, which is a simple spiked weapon with two or more legs that always lands with one spike pointed up. Metal versions of these weapons have been used since Roman times; it was easy to fling them in the path of an approaching enemy. Puncture vine seeds smeared with the juice of Acokanthera would have been an efficient way to embed the poison in the feet of an attacker, and the half-inch-long spines would slow them down considerably.
ILLEGAL
Ayahuasca Vine
BANISTERIOPSIS CAAPI
and Chacruna
PSYCHOTRIA VIRIDIS
William Burroughs drank ayahuasca tea in the jungle and reported his findings to Allen Ginsberg. Alice Walker sought it out, as did Paul Theroux, Paul Simon, and Sting. It has been the subject of a patent dispute, a Supreme Court case, and a number of drug raids.
BANISTERIOPSIS CAAPI
FAMILY:
Malpighiaceae
HABITAT:
Tropical forests in South America
NATIVE TO:
Peru, Ecuador, Brazil
COMMON NAMES:
Yage, caapi, natem, dapa
The bark of the woody ayahuasca vine, brewed with the leaves of the chacruna shrub, form a potent tea called ayahuasca (or, alternatively, hoasca). Chacruna contains the powerful psychoactive drug DMT (di-methyltryptamine), a Schedule I controlled substance, but the leaves must be activated by another plant, usually Banisteriopsis caapi, before the effects can be felt. The latter contains a naturally occurring monoamine oxidase inhibitor, similar to the compounds found in prescription antidepressants. Put the two together, and you’re in for a mind-altering experience.