Cirsium horridulum
Asteraceae
John and George last week explored a low pine woods with marshes, ponds, and Sandhill Cranes in the West Jupiter Wetland. The site was a floral showplace of White Violets, Pineland Daisies, Yellow Sneezeweeds, Orange Milkworts, and more in colorful bloom. The trailside all-stars were native Purple Thistles, Cirsium horridulum.
Nothing could be less horrid than this proud wildflower. (The “horridulum” presumably relates to the thorns on the foliage and on the bracts under the flower head.) Thistles are especially happy plants for me, evoking childhood memories of bike rides, railroad tracks, and cows in the pasture.
The broad term “thistle” embraces several thorny members of the Composite Family. The name is ancient, as are writings about thistles. They’re the symbol of Scotland, according to lesson, due to the painful spines tipping the fate of battle. You can scarcely find a plant group applied medicinally in more ways. Uses include treating swollen veins, controlling blood sugar, and relieving gastrointestinal discomforts.

Thistle uses extend beyond medicine. Thistles solidify cheese as a vegetable rennet. And there’s nothing cozier than a goldfinch nest lined with thistledown. Thistledown provides the poofy end for blowgun darts. CLICK Ever notice the similarity between artichokes and thistles? Artichokes are thistles of sorts, and weedy thistles, including C. horridulum, have had their soft inner regions served in foods.

What do you do if your pastures invaded by exotic thistles? Find a natural enemy of course and introduce it to smite those uninvited botanical guests. But watch out…that can backfire if the pest plant has native relatives. A weevil introduced from the Old World to control Old World Thistles in American pastures broadened its palette to native thistles, including our own Cirsium horridulum. The full extent of the problem remains to be seen.



Mary Hart
February 16, 2013 at 4:06 am
Like you, thistles are a conduit for happy memories – photographing my 5-yr. old son 40 odd yrs. ago watching bumble bees on thistle flowers. Thistles bring so much colour to fields and byways.
George Rogers
February 16, 2013 at 7:39 am
My thoughts exactly! Thanks Mary.
FeyGirl
February 17, 2013 at 8:28 pm
Beautiful images… And FASCINATING!
George Rogers
February 17, 2013 at 8:35 pm
Thanks—such a nice note to end a tiring day!
annsbirdventures
February 20, 2013 at 9:00 am
It may be my Scottish ancestry, but I’ve always loved thistles. I’ve tried to sort them out in N.C., but I think I’ll have to send you a photo this summer and see what you think. I hope they’re the natives ones! I won’t let the weedeaters near them til I find out.
Thanks, George, for your always- fascinating articles.
Ann
George Rogers
February 20, 2013 at 9:41 am
Hey Ann, you can’t love birds and not love thistles! Protect them because thorns don’t stop weedeaters. I soooo miss NC! Needed you yesterday, due to a vocal but unidentified bird who joined the native plants class unmatrculated.
annsbirdventures
March 1, 2013 at 12:55 pm
I really wanted to come on that field trip but we were leading our own at Merritt Island National Wildlife Refuge in Titusville. Next time!