SCIENCE

Wicked Plants (and Fungi)

May 14, 2009

How could I resist a book with the title Wicked Plants: The Weed That Killed Lincoln’s Mother & Other Botanical Atrocities? This small, elegant volume by Amy Stewart packs in a ton of information on plants that have been used to murder or to intoxicate, some that can inflict pain or cause hallucinations, and others that are “badly behaved” or are just illegal.

The main entries for individual plants include common names, habitat and descriptions as well as stories from history. In the henbane entry, for example, Stewart mentions that the vegetable had been added to beer in the Middle Ages to enhance the intoxicating effects of the brew and that it was in part to eliminate it (and other “suspicious” ingredients) from beer that the Bavarian Purity Law was passed in 1516.

Interspersed are sections that group several plants (and in one, fungi) with similar effects, such as “Stop and Smell the Ragweed.” This entry particularly struck me, as we are deep into allergy season. There are several common garden trees and plants that could be the culprits in our suffering. The mulberry, for one, sheds billions of pollen grains. And it turns out that while Bermuda grass may be popular in the South, it is also one of the most allergenic of the grasses.

There are surprises throughout the book. Many familiar plants have hidden dark sides. My favorite flowers, tulips, produce an irritating sap—a reminder to wear my garden gloves when planting bulbs. And while there are the expected murder stories, more worrisome are the numbers of people who have died eating plants that they didn’t recognize or misidentified or simply didn’t think could be dangerous. Children and pets are, sadly, the most common victims. This is a reminder to not experiment with unknown vegetation, ever.

My one criticism is that the book lacks an index, which makes it difficult to find any specific plant, especially those that have entries only within groups. Overall, though, it is a fascinating read and a must-have for botanists and budding mystery writers.

Oh, and what was the weed that killed Lincoln’s mother? Well, that was white snakeroot (Eupatorium rugosum), which when eaten by cattle, poisons the milk and causes milk sickness. Symptoms include weakness, vomiting, tremors and delirium. Nancy Hanks Lincoln, her aunt and uncle and several other townspeople succumbed to the disease in 1818.