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..2 Disc florets 8-14; lower cauline leaves deltate
..2 Disc florets 18-55; lower cauline leaves hastate to deltate or lanceolate
....3 Herbage glandular, fetid, and viscid
......4 Subshrubs; herbage glabrous; stems usually multiple, branching upwards
........5 Ray flowers 0; calyculi bractlets black-tipped; [alien, widespread]
..........6 Plants 3-7+ dm; herbage loosely arachno-tomentose, unevenly glabrate or glabrescent; mid-stem leaves lanceolate, 3-10 cm (bases tapered or truncate, sometimes clasping)
..........6 Plants 8-12 dm; herbage glabrous or glabrate; mid and upper leaves ovate to broadly lanceolate, 10-20 cm (bases clasping)