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Yellow Thistle

Cirsium horridulum


Clearly a large thistle, but I can't identify it. Leaves streaked heavily with red-purple don't seem to match anything. And the color of the flower, deep reddish-maroon, isn't typical of other large thistles, which tend to be light purple. An odd Bull Thistle, maybe?


Along the edge of a rural road. Growing by a ditch which carries water at times, but was dry the day I took these photos. The foliage at the base of the plant looks like a giant dandelion. Each plant had, usually, one flower ... occasionally two or three ... but never clusters. Around it, grasses, buttercups, a field that looked like it was probably used to graze dairy cattle. The photos are of two or three plants, but they weren't the only ones ... there were 10 or more within just a few steps.


For awhile, I thought maybe the thistles I photographed that day were Bull Thistles whose leaves and flowers were given an atypical color by the presence of an unusual substance in the ground. Kind of the way, supposedly, you can change the color of a hydrangea by sticking nails in the dirt around it ... I don't know if that's true, maybe just an an old wive's tail.

But that's not it. I've seen other large thistles this color throughout the region over the years. It's probably going to end up to be something really easy, but I've been fooling around with an ID for a couple of years ...

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suzmonk 10 years ago

It does, doesn't it? Especially the second photo ... fierce.

EmilyUmbarger 10 years ago

This was definitely NOT an easy one! hah I'm glad to have helped. (If truth be told, it reminded me from something you might have seen in Little Shop of Horrors!) :)

suzmonk 10 years ago

Well, at least it wasn't an easy one! So, the big, deep-red thistle is called Yellow Thistle. Go figure, but I think you're right. Thanks so much for your help! This thistle has been bugging me for three years ... and yes, they are beautiful.

EmilyUmbarger 10 years ago

I'm pretty sure this is the horridulum species. Ironically called the yellow thistle, only rarely are the blossoms actually yellow. They are more often red/reddish purple/purple. I had a lot of fun looking this one up! Beautiful thistle!

Spotted by

Macon, Mississippi, USA

Spotted on Apr 28, 2010
Submitted on Jul 4, 2013

Spotted for Mission

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