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DescriptionThis perennial wildflower is 1-3' tall, branching frequently. The stems are light gray-green, terete, and sparsely to moderately covered with short fine hairs. The alternate leaves are 1½-3' long, ¾-1½' across, and lanceolate, oblanceolate, or ovate in outline; each leaf is pinnate-pinnatifid with 2-6 pairs of lateral leaflets and a terminal leaflet. The leaflets are oblong in shape and pinnatifid with pointed lobes. The upper surface of each leaf is light to medium gray-green, while the lower surface is light gray-green; both surfaces are sparsely to moderately covered with short fine hairs. The lower leaves have short flat petioles, while the upper leaves are sessile or nearly so. The upper stems terminate in individual flowerheads about 1½-2' across. Each flowerhead consists of 20-32 yellow ray florets that surround a large dome-like cluster of golden yellow disk florets. The ray florets are fertile and pistillate (female); the petaloid (petal-like) extension of each ray floret terminates in 2-3 blunt teeth. The tiny disk florets are fertile and perfect; the corolla of each disk floret is narrowly tubular with 5 spreading lobes. Around the base of each flowerhead, there are numerous phyllaries (floral bracts) that are arranged together in a single series. Individual phyllaries are light green, linear in shape, and membranous along their upper margins; they are sparsely to moderately covered with short fine hairs. The peduncles (stalks) of the flowerheads are relatively long and unbranched; they are similar in appearance to the stems. The crushed foliage has an aromatic scent. The blooming period occurs from mid-summer to early fall, lasting about 2 months. The florets are replaced by narrowly oblongoid achenes about 2 mm. in length; these achenes are slightly four-angled and slightly flattened. At the apex of each achene, there is a short angular crown.