Milksickness Madness
The Autumnal Equinox has just passed. Summer wildflowers are beginning to fade. It is also a time, codified in American history, that the season of “milk sickness” would soon end.
“The localities of the ‘milk sickness,’ so far as they have been ascertained, are limited to portions of some of the Middle, Southern, and Western States of the Union,” wrote Solon Borland, M.D. in his 1845 treatise, An Essay on The Milk Sickness of the Human Subject of the Trembles of Animals, published in Little Rock.
In addition to Arkansas, “It is common to the States of Virginia, North and South Carolina, Georgia, Alabama, Tennessee, Kentucky, Ohio, Indiana, Illinois, and Missouri.” Cases “are most prevalent during the seasons when vegetation is most active and abundant … All observers agree that the disease never occurs in very cold weather. Let this be borne in mind.”
First described by Dr. Thomas Barbee in Bourbon County, Kentucky, in 1809, the milk sickness plagued middle American settlers from the colonial era to the 20th century. The most famous victim, Abraham Lincoln’s mother, Nancy Hanks Lincoln, died October 5, 1818.
The milk sickness affected entire families and destroyed communities. The only way to contract the disease was by drinking milk or eating butter. Livestock, especially horses, cattle and goats, would die in a few days once they exhibited symptoms of the “trembles,” a neurological disorder.
By the early 20th century, the suspected culprit was a plant called White Snakeroot. In 1908, a USDA researcher, A. C. Crawford authored a USDA Bulletin “The supposed relationship of white snakeroot to milksickness or trembles.” He proved that the dried plant produced no symptoms of milk sickness when fed to laboratory animals. But he missed a key clue. Milk sickness only occurred during the growing season before the first frost of autumn—when the plant was fresh.
It was not until 18 years later, in 1926, that another USDA chemist, James F. Couch, showed that fresh, not dried, White Snakeroot caused milk sickness. The following year he isolated the chemical complex—tremetol—as the toxic component.
Blooming now, this native wildflower has white button-like flowerheads, up to a half-inch across, crowded with small star-shaped white flowers. Botanists have called it Eupatorium rugosum and Ageratum altissimum, but today it is known as Ageratina altissima. Indeed, the devil is in the details.