[Cal-IPC] Invasive: Carthamus lanatus (woolly distaff thistle) is a winter annual forb (family Asteraceae) found in disturbed open sites, roadsides, pastures, annual grasslands, and waste areas. Its spiny foliage can injure livestock. It is primarily found in the northern coast ranges of California.
Cal-IPC Rating High (link added by Mary Ann Machi)
[Wikipedia] Mediterranean Basin native, Noxious weed: Carthamus lanatus is a species of thistle known as woolly distaff thistle,[1] downy safflower[2] or saffron thistle. It is closely related to safflower (Carthamus tinctorius). This annual plant is a native of the Mediterranean Basin, but it is familiar in other places where it was introduced and has become a noxious weed, such as in parts of North America and southern Australia[3] with similar climates. (link added by Mary Ann Machi)