Rattlesnake master

The botanical name, Eryngium, is from the Greek meaning thorny or prickly and the specific epithet yuccifolium refers to the similarity of the leaves to those of Yucca. Eryngium yuccilfolium is in the Apiaceae family (celery, carrot or parsley family).

The common name, Rattlesnake master, came from the erroneous belief that this plant could be used to treat snake bites.

Rattlesnake master has some of the most unique flowers among our native flora. Each globe shaped, spiky inflorescence consists of many (over 100) tiny individual white flowers. A mature plant will have anywhere between 10-40 flowering globes with each containing many minute florets. Each floret is composed of 5 petals with 5 stamens. The stamens have greenish-white filaments and greenish anthers. Florets are subtended by small bracts with the flowering globe subtended by larger, triangular bracts with pointed tips. Each floret has a pair of styles that appear ahead of the stamens. Flowering begins in June and may extend into August.

The distinctive appearance of Rattlesnake master makes it a charming standout in the grassland, glade or garden setting. The flowers (fresh or dried) are also long-lasting in a bouquet (if you can stand to cut them!).

Eryngium yuccifolium is a long-lived perennial wildflower with unique grayish-green coloration. It typically grows to a height of 4-5 feet. Basal leaves are whorled. Stem leaves are alternate and clasp the stem. All leaves are thick and lanceolate in shape with bristly edges. The inflorescence is subtended by prominent leafy bracts (orange circle in image below).

The flowers turn brown and bristly when the seeds are ripe for harvesting.

The unusual flowers of Rattlesnake master are highly sought after by many varied insects. Various types of bees, wasps, flies, butterflies, skippers, beetles and plant bugs can be found visiting the flowers. An extended list of many insect visitors can be found on the website, Illinoiswildflowers. Below you'll find photos of the insects I've documented in Arkansas.

Many types of wasp visit the flowers of Rattlesnake Master. Some are quite beautiful with interesting markings or green eyes! I am particularly fond of the large Horse guard wasp as it preys on horse flies, which my horse despises.

I see many more wasps than bee visitors. The metallic green sweat bees are particularly beautiful, but as they are quite small, their beauty is easier to appreciate on photographs!

Butterflies

Other insect visitors-

There are so many insects visiting these flowers and sometimes they get testy with each other. Take a look at this battle between an Assassin bug and a couple of Green sweat bees!

Rattlesnake master isn't too picky about its habitat. It does very well among grasses and other forbs in the full to partial sun of prairie habitat. It also does well in the hot, rocky ozark glades. In fact, it will thrive just about anywhere except for full shade or wetland. Overall, this is an easy-to-please native plant.

While Natureserve lists Rattlesnake masters as Secure, most of the states in its range lack status ranking on the site. It is listed as Secure in Georgia and North Carolina, Apparently Secure in Iowa, Vulnerable in Ohio, Imperiled in Virginia and Michigan. It is Critically Imperiled in Nebraska and Possibly Extirpated in Maryland. All other states within its range show No Status Ranking.

In Arkansas, Erynigum yucciflium has a Conservation value of 8, meaning "Conservative taxa with strong fidelity to intact habitats". "These taxa tend to exhibit late-successional characteristics like long lifespans with low seed sets and an inability for far ranging dispersal."

Prehistoric sandals discovered in Missouri were found to use fibers from Eryngium yuccifolium for padding.* What a great idea. I can imagine that layers of the thick yucca like leaves of Rattlesnake master could be very comfortable in the sole of a pair of sandals. The sandals were discovered in the 1950s and were dated using accelerator mass spectrometry in 1977.

*Science.1998 Jul 3;281(5373):72-5. doi: 10.1126/science.281.5373.72.