Musk Thistle

flowers emerge in early May to August and may produce 1,200 seeds per head and as many as 120,000 seeds per plant. Seeds may remain viable in the soil for over ten years.
is usually a biennial although it may germinate and flower in a single year. It typically grows in open disturbed soil or heavily grazed areas.
generally prefers to grow in pastures because the drainage is good, and livestock will avoid it due to its spiny leaves and stems.

Small areas can be eradicated by digging. Plants must be cut off below the soil, leaving no leaves attached. Mowing usually prevents seed production, if done prior to flowering. When plants are cut or mowed late in the flowering stage, viable seed can still develop. Because there can be a wide variety in the maturity of plants, a single mowing is not likely to provide satisfactory control.
Establishing and maintaining dense, vigorous, competitive pasture can effectively prevent establishment. Healthy pasture is particularly important in the autumn, when most thistle seeds germinate. It is important not to over-graze pastures or dry rangeland areas.
There are herbicides on the market that have proven effective. Non-crop, grass-friendly products like Milestone, Redeem, Transline, Curtail, Escort, and Telar have proven to be the most effective. Late season treatments of Telar may temporarily injure cool season grasses. Other products such as those containing 2,4-D or Dicamba have also been used. Treatments should be applied during the rosette stage through bolt, and late in the fall. Always read and follow the label when using any herbicide.