Shedding a Dark Light on Suspicious Species

Sunday, May 31, to Sunday, September 6, 2009

Scoundrels or Saints?
Shakespeare Garden

Monkshood (Aconitum species).
Photo: Gertrude K.

Audio Tour

Yew and Harry Potter?

Amy Stewart explains this plant's wicked role in culture and history.

(1:47)

Complete Audio Tour

Lurking amid the tranquil beauty of the Shakespeare Garden are plants offering great benefits—and terrible consequences. A prime culprit here is monkshood, a member of the buttercup family. All parts of the plant are toxic—even sap on the skin can distress the heart. The root resembles that of horseradish, but confusing the two could prove fatal.

Canine connections: The ancient Greeks believed Aconitum sprang from the saliva of Cerberus, the horrible three-headed hound guarding the gates of hell. One alias for the plant is wolfsbane, and in fact, the plant's toxins were once used on arrows to fell wolves. It has also been associated in legend with both the creation and killing of werewolves.

Illustration: Hercules Capturing Cerberus, by Hans Sebald Beham, 1545

Monkshood's powerful alkaloid poison lowers blood pressure, affecting nerves and muscles. The throat numbs, the stomach burns, and vomiting ensues. Heartbeat and respiration slow. Death comes from suffocation.

Nonetheless, like many toxic plants that have been used therapeutically, such as foxglove (Digitalis species) and wormwood (Artemisia absinthium), monkshood has its good side. This charming killer has been used for centuries in traditional Asian medicine—processed in tiny amounts to treat fever, “coldness,” and even appendicitis. Until recently Western doctors used it to numb pain.

This devious flower is composed of lovely purple sepals, more commonly a layer of green or brown leaflike structures protecting a bud or blossom. Here, the single large sepal at the top resembles a cowl, or hood, lending it the common names monkshood and—more sinisterly, devil's helmet.

In Harry Potter and the Sorcerer's Stone, Professor Snape asks Harry the difference between monkshood and wolfsbane. Harry doesn't know the answer. Now you do—they are the same plant!