[TEXT ARCHIVE WEB-PUBLISHED MAY 2001.
ORIGINAL PRINT PUBLICATION DATE: FALL 1997.]

Rattlesnake master: Signal species that thrives in quality prairies

By Sheryl De Vore

Early settlers hiking through the 7-foot-tall big blue stem dominating the Chicagoland region’s tallgrass prairies encountered plenty of snakes. They also saw an unusual looking plant they dubbed the rattlesnake master (Eryngium yuccifolium). They believed that rubbing a mixture of the plant’s roots and yucca-like leaves on their skin would heal snake bites.

While there’s no proof this particular herbal remedy works, the name of the plant has endured, and thankfully, so has the plant. In fact, botanists consider the presence of rattlesnake master the sign of a relatively undisturbed prairie. "I can’t ever recall ever seeing one except on expanses of quality prairie," wrote John Madson in his book, Where The Sky Began, Land of the Tallgrass Prairie.

Rattlesnake master has stiff, yucca-like, sharply toothed leaves and grows up to four feet tall. It thrives among big blue stem, compass plant, and other grasses and forbs in mesic or moderately wet tallgrass prairies. It can also sometimes be found in woodlands but rarely, if ever, on edges or disturbed land.

The rattlesnake master has adapted well to harsh prairie life. Sunken pores in the leaves’ upper surfaces reduce water loss during hot, dry summers. Strong cells in the plant’s margins and veins make it difficult for grasshoppers and other prairie insects to chew. They usually give up before causing the plant any damage. The new spring growth, however, provided a tasty, nutritious meal for the earlier human inhabitants of the Chicago Wilderness region.

By summer, the plant has reached its prime. Then, tiny white flowers, almost undetectable to the naked eye, emerge, upon 1-inch round, thistle-like heads. Only with a magnifying glass can one see the flowers’ five sepals, petals, and stamens.

The flowers may not be showy, but the plant is. Scattered in clumps among the grasses, the rattlesnake master appears unchallenged, with its globe-like flower heads blown freely by the wind, adding a new dimension to the flat expanse of the prairie.

While providing an interesting texture to the grassland scenery, the rattlesnake master also offers a home to a state-endangered species, a beautiful and rare moth called the rattlesnake master root borer. Thought extinct, this rare moth was rediscovered at Goose Lake Prairie in Grundy County.

To see this unique member of the parsley family, head for one of your favorite prairies and search for the rattlesnake master.