Lots of big thistles are blooming now by the road to Duck Hollow in Pittsburgh. At first I couldn't identify them but my guess was that anything growing so well by the road was probably alien and invasive. I was right.
Nodding thistle or musk thistle (Carduus nutans) is a biennial from Africa and Eurasia that came to this continent by accident, perhaps in ballast water. It thrives in disturbed soil at roadsides and landslides and in heavily grazed pastures. It's a thorn in the side for cattle farmers and an alien invasive.
A view of the entire plant shows many thorns and the reason why its called "nodding."
Despite its mean reputation, I think it's beautiful. The buds look like reddish-purple star bursts as they open.
And the color of the flower is outstanding. My favorite view is too wide for this blog's narrow format so click here for a closeup of color without thorns.
(photos by Kate St. John)