IDENTIFICATION — All the surfaces of the leaves and stems of musk thistle are covered with sharp prickles. The spiny multi-branched stems reach 2 to 6 ft. tall. From summer to fall, its showy red-purple flowers open, the flower heads drooping as they age.
FAVORITE CONDITIONS — The seeds of this biennial weed sprout in summer, in full sun or shade, in areas not regularly cultivated, such as fence rows, garden perimeters and lawns.
CONTROL — Sharp spines make hand-pulling this weed difficult. So hoe the young plants or spray a broadleaf herbicide before the seeds ripen.