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DescriptionThis adventive biennial plant is a low-growing rosette during the 1st year. During the 2nd year, it sends up one or more flowering stems 1-3' tall. These stems branch sparingly above the withered remains of the rosette. Each stem is round, hairless, and often somewhat enlarged at the base of each leaf. The cauline leaves alternate sparingly and become smaller as they ascend the stems. They are up to 12" long and 1" across, lanceolate-linear in shape, smooth along the margins, and hairless. Their veins run parallel to each other, and at the base each leaf strongly clasps the stem. The basal leaves are similar to the cauline leaves in structure and appearance. Both the stems and leaves contain a white latex. Each stem terminates in a long naked stalk bearing a single flowerhead. Each flowerhead is about 2" across when fully open, consisting of numerous yellow ray florets and about 8 green floral bracts that are lanceolate-linear in shape. The ray florets spread outward from the center of the flowerhead; the outer florets are noticeably longer than the inner florets. Each floret has a truncated tip with 5 small teeth. At its base, there is a columnar reproductive structure consisting of a yellow divided style and black anthers that are appressed together around the middle of the style. The floral bracts extend to about the outer margin of the flowerhead; sometimes, they are a little shorter or longer than the width of the flowerhead. The blooming period occurs from late spring to mid-summer and lasts about 1–1½ months. The flowerheads open up during the morning and close again by the afternoon. Each floret is replaced by an oblong achene that has a long thread-like beak, to which there is attached a tuft of hairs. These hairs are slightly plumose because they contain small hair-like branches. They are usually white at the base, but become dull brown toward their tips. Collectively, these achenes with their tufts of hair form a large spheroid ball that spans about 3–3½" across. Distribution of the achenes is provided by the wind. The root system consists of a fleshy taproot. This plant spreads by reseeding itself.