Wicked Plants (2 page)

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.

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.

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.

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.

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:

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.

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.

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.

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.

BANISTERIOPSIS CAAPI

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.

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.

One of the best-known religious groups to use the tea is União do Vegetal, or UDV. Its ceremonies usually last for several hours and are closely supervised by a more experienced member of the church. Participants experience bizarre hallucinations; one described it this way: “Dark creatures sail by. Tangles of long, hissing serpents. Dragons spitting fire. Screaming humanlike forms.”

The experience usually ends with severe vomiting. The vomiting is seen as a kind of purge of psychological problems or demons. People who have participated in the ceremony report that it relieved their depression, cured their addiction, or treated other medical problems. Although there is little clinical evidence to support this, ayahuasca’s similarity to prescription antidepressants has interested some researchers, who have called for more detailed studies.

The tea also attracted the attention of Jeffrey Bronfman, a member of the wealthy family that founded Seagram, makers of whisky and gin. Bronfman formed a branch of the UDV church in the United States and began importing the tea. In 1999 his shipment was intercepted by U.S. Customs agents, and Bronfman sued to have the tea returned to him. The case landed in the Supreme Court, and in 2006 the court ruled in his favor, allowing the use of the tea for religious purposes. The court’s ruling was based primarily on the Religious Freedom Restoration Act, which
Congress had passed in response to an earlier Supreme Court ruling against the use of peyote for religious purposes. According to news reports, the church, known as Centro Espírita Beneficente União do Vegetal, has 130 members and meets at Bronfman’s home in Santa Fe. The U.S. Drug Enforcement Administration continues to enforce the laws against nonreligious use of ayahuasca and other products containing DMT.

Meet the Relatives
   
Banisteriopsis Caapi
is a member of a large family of flowering shrubs and vines found primarily in South America and the West Indies.

Meet the Relatives
   
Psychotria viridis
is a member of the coffee family; relatives include cinchona, the quinine tree, and the poisonous ground cover sweet woodruff, which flavors may wine. Another powerful vine in the same genus is
P. ipecacuanha
, from which a treatment for plant poisonings, syrup of ipecac, is made.