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..2 Flowers yellow; middle and outer phyllaries hispid; heads usually 5-8 mm across at anthesis, the involucre campanulate
..2 Flowers white; middle and outer phyllaries glabrous or puberulent; heads usually 2-4 mm wide at anthesis, the involucre cylindric
....3 Plants glabrous or apparently so; plants mostly annual
....3 Plants conspicuously pubescent, as on the hispid leaves; plants mostly perennial