Southern Europe, the Mediterranean, and Central Asia
Musk thistle is an upright forb that typically grows as a biennial but can also grow as a winter annual. Plants grow 5 ft (1½ m) tall on average from a fleshy taproot. Leaves are large, dark green, hairless, waxy, and coarsely lobed with white, spiny margins. Stems are stout and have spiny wings along their lower sections only. Flower heads are solitary at the ends of stems and branches. They have magenta florets and purple, wedge-shaped bracts. Seeds are straw-colored and topped by a tuft of fine hairs.
Introduced thistles currently infest millions of acres across North America, primarily occurring in or along roadways, waterways, agricultural fields, rangelands, pastures, forests, and disturbed areas. They are responsible for millions of dollars of damage annually in reduced agricultural yields and lowered forage value in grazing systems. Introduced invasive thistles can also displace native vegetation, negatively impacting wildlife and threatening the delicate ecological balance within many habitats.
Randall, C.B., J.E. Andreas, and J. Milan. 2024. Introduced Thistles: History and Ecology in North America. In: R.L. Winston, Ed. Biological Control of Weeds in North America. North American Invasive Species Management Association, Milwaukee, WI. NAISMA-BCW-2024-8- INTRODUCED THISTLES-P. https://bugwoodcloud.org/resource/files/29168.pdf