General Information |
Distribution | Native from southern Canada and the United States south to tropical America, widely naturalized.
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Habit
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Plants green, 1-15 dm tall, unbranched or nearly so to the inflorescence, glabrous to coarsely hirsute.
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Leaves
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Leaves numerous, oblanceolate to linear, those of the central half of the stem 4-10 cm long, 0.3-0.6 cm wide, the basal ones deciduous and broader, becoming progressively reduced above, margins entire to toothed.
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Flowers
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Heads usually numerous; involucre 3-4 mm high, bracts sometimes purple-tipped, glabrous or with a few small scattered hairs; ray florets 25-40 per head, female, rays 0.5-1 mm long; pappus yellowish to yellowish brown, in a single series, somewhat longer than the inner florets.
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Chromosomes
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2n = 9, 18, 32, 54
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