Thank you for bringing this plant to our attention.
I had heard of rattlesnake master plants though I was not sure what they looked like.
Of course, the name “rattlesnake master” prompts all kinds of suggestions as to potential medical uses. The best documented use, made by John Adair during the 1700s, describes the use of the plant’s sap as a preventative to snakebite, used during ceremonial handling of rattlesnakes. The sap and roots were also used to treat a wide variety of maladies and as a diuretic. The Mesquakies used it in their ceremonial rattlesnake dance and used the roots to treat rattlesnake bites.
In the prairie or in the garden, rattlesnake master is a favorite of native insects. Monarch butterflies, skippers, and other butterflies visit the flower heads for nectar. Soldier beetles visit the flowers to eat pollen; major pollinators include a diversity of bees, wasps, and flies.
https://www.fs.usda.gov/wildflowers/plant-of-the-week/Eryngium-yuccifolium.shtml
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