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..2 Inflorescence of (1-) 2-20 heads, in a corymbiform array; disc flowers red to maroon
..2 Inflorescence of 1 (-3) heads; disc flowers yellow
....3 Leaves lyrate-pinnatifid; [ne. TX westward]
......4 Hairs of the stem thick-based, erect, mostly 1.0-1.5 (-2.0) mm long, commonly distinctly flattened and vitreous; lower leaf surfaces greenish; leaves lanceolate to deltate, the mid- and upper-stem leaves sessile; stem internodes mostly < 3 cm long
........5 Upper leaf surfaces generally softly pubescent with very thin, basally appressed or basally reclining hairs; leaves strongly, weakly, or not at all bicolored; stem vestiture relatively dense and matted (or less so); hairs of the stem whitish, or with purplish cross-walls near the base of the hair only; [more widespread]
........5 Upper leaf surfaces hispidulous-scabrous with thick-based hairs that are basally erect; leaves not bicolored; stem vestiture only moderately dense, the stem surface visible; hairs of the stem often reddish-brown to purple because of dark cross-walls; [w. LA and e. TX]