Oh, good heavens no! Those are the ones I'm having issues with as well as what's called Scotch cottonthistle.
In fact, in Missouri, both of those species are considered noxious weeds, and according to Missouri statute #263.460, "the prosecuting attorney for each county declared a noxious weed control area may bring an action in the circuit court of the county to enjoin such nuisance."
Anyway, I can't stand 'em.