Origin:
A native of Eurasia that was introduced to the United States in the late 1800’s, and now is widely distributed over the western U.S.
Biology:
This is a perennial weed with very extensive and deep root systems, with reproduction not only from seed but also from the creeping roots. Plants are not poisonous, but they are bitter and unpalatable to livestock, making their common presence in hay fields a problem.
Identification:
Mature plants are bushy and well-branched, and may be 3 feet tall. The stems are erect and are covered with grayish white, soft hairs. The plants are heavily leaved, with the leaves having several shapes. The basal leaves may be narrow and up to 5 inches long, and have margins that are deeply lobed. Leaves higher up on the stems have no stalks, may be only 2 inches long, and are only slightly lobed along their margins. At the upper areas of the plant the leaves are narrow and have smooth margins. Flower heads grow at the ends of nearly all the branches of the stems as solitary heads. The bracts form a large, swollen cone enclosing the flowers, and the flowers are composed of violet ray flowers that are long and thin, giving it an overall soft appearance.
Characteristicts Important to Control:
Roots can be as deep as 8 feet and are widely spreading, with new shoots growing from these roots. Physical removal would be very difficult.
