Musk Thistle

Musk Thistle (also known as Nodding Plumeless Thistle) is a striking flower. There is only one flower per stem, which is somewhat unique among thistles, and they have no ray flowers, which is unique among composite flowers.

 

Unfortunately Musk Thistle (Carduus nutans, Carduus macrocephalus) is deemed an invasive alien species in Colorado.

Done