Button Rattlesnake Master
Today John Bradford and George Rogers wandered through the Sweetbay Natural Area adjacent to the Palm Beach North County Airport. The area is named for the Sweetbay Magnolia (Magnolia virginiana), but this post will feature a much odder plant that was in full bloom today.
What plant looks like a yucca straight from the desert, has white flowers packed into congested heads like so many other locally abundant species, and smells like carrots when bruised? The Button Rattlesnake Master: Eryngium yuccifolium. The globe-shaped heads of small white flowers resemble those of Buttonbush (Cephalanthus occidentalis) and Buttonweed (Spermacoce verticillata, not native). All three were in flower in close proximity. It would be interesting to know how much overlap they have in flower visitor species. Probably much. Many species visit the Eryngium.
Being a member of the Carrot Family (Apiaceae), it comes by the carrot smell honestly. And, yes, the plant has a taproot. The long skinny leaves look more like those of a Monocot (such as a true yucca or a grass) than the Dicot this species is. Around here the plants reach about three feet tall.
Eryngium yuccifolium is odd and beautiful enough to be a garden plant, and it is, being started readily from seeds. The species is distributed across the southern and central U.S. from Florida to Minnesota in diverse wet and dry habitats ranging from limestone glades to pinewoods to tall grass prairie, all demanding the characteristic of requiring durability, especially to withstand fires—burning pine woods in the South and burning prairies in the mid-West. When the top fries or dies, regeneration comes from the taproot.
Why the name “Rattlesnake Master”? According to some accounts, Native Americans rubbed the pulverized root onto the hands to gain mastery over rattlesnakes. (Relevantly somehow, on a prior visit to Sweetbay we encountered a pygmy rattler at the very site where the Eryngium grows.) According to other reports, the name has to do with historical uses to treat snakebites. Extracts from Eryngium roots reportedly reduce inflammation, so the snakebite treatment is a folk use with potential extension into modern pharmacology.
Maturation of the flowers is protogynous (pro-TOJ-eh-nus), that is, female first. The stigmas poke out early between the petals, with the flower remaining otherwise closed. The closed petals hold the stamens in. Eventually the petals spread, the stamens emerge, and it is male-time. The male and female phases overlap, and the flowers are self-compatible, resulting in high seed production. Neat system-eh? The flower is receptive to outside pollination before it can pollinate itself. If there is no outside pollination, then the flower self-pollinates as Plan B. (This post is a collaborative effort by John Bradford and George Rogers. JB took the plant picture. GR took the scenic vista.)