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DescriptionThis native perennial wildflower is 3-7' tall and largely unbranched, except at the apex, where the flowering stalks occur. The central stem is light green or pale purple, terete, glabrous, and sometimes glaucous. The alternate leaves are 3-5" long and 1/32/3" across, becoming only slightly shorter while ascending the central stem. Sometimes there are leafy lateral stems that develop from the leaf axils of the central stem, but they are very short and insignificant. The alternate leaves are narrowly lanceolate to elliptic, slightly to sharply toothed along their margins, and sessile; each leaf tapers gradually towards its tip and base. The upper surfaces of the leaves are medium to dark green and glabrous, while their lower surfaces are a slightly lighter shade of green and glabrous or nearly so (sometimes there are fine hairs along the major veins below). Each leaf has 3 veins (a central vein and 2 lateral veins) that are nearly parallel to each other. The central stem terminates in a panicle of flowerheads up to 1' long and 1' across. There is some variability in the shape and size of the panicle across different populations of plants. Individual branches of the panicle are light green, slightly to moderately pubescent, and recurved. There are usually some leafy bracts along the branches of the panicle; these leafy bracts are similar to the leaves, except they are smaller in size. Individual flowerheads are a little less than ¼" across, consisting of about 7-15 yellow ray florets and 5-11 yellow disk florets. At the base of each flowerhead, there are appressed floral bracts in 2-5 overlapping series; individual floral bracts are linear-lanceolate in shape. The blooming period occurs from late summer to early fall for about a month. Both ray and disk florets produce small achenes with sessile tufts of hair. The achenes are bullet-shaped, flat-topped, and finely pubescent. The root system is fibrous and rhizomatous. Colonies of plants are often formed from the rhizomes.