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DescriptionThis introduced perennial plant is 1-3' tall and little branched. The central stem is glabrous to slightly hairy and often angular or furrowed. A small tuft of basal leaves develops at the base of the plant, while alternate leaves occur sparingly along the central stem. These leaves are up to 5" long and ¾" across, becoming smaller as they ascend the stem. The basal and lower leaves are often oblanceolate with slender petioles, while the middle to upper leaves are more oblong and often clasp the stem. Their margins are coarsely dentate, and some of the alternate leaves are often pinnatifid toward the base. The upper and lower surface of each leaf is hairless (or nearly so). The central stem terminates in a single flowerhead on a long stalk that is nearly naked. This flowerhead spans about 1¼2" across and has a typical daisy-like appearance. It consists of 15-35 white ray florets surrounding numerous tiny disk florets that are yellow. The receptacle of the disk florets is noticeably flattened. Each disk floret has 5 tiny lobes at its apex and is perfect, while each ray floret consists of a white oblong petal and is pistillate. At the base of the flowerhead, are several series of green floral bracts with margins that are brown and membranous. The blooming period occurs during early to mid-summer and lasts about 1½ months. Each floret is replaced by an oblongoid dark achene that has about 10 light ribs. The achenes are without tufts of hair. The root system is densely fibrous and forms offsets from short rhizomes. This plant often forms dense colonies where it is allowed to grow undisturbed.