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|1 Leaves basally disposed, the basal leaves (these sometimes withered by flowering season) and/or lower stem leaves larger than the upper stem leaves; leaves (at least the lower stem or basal) toothed.|
|..2 Plant with a short, thick, fibrous-rooted rhizome that produces short basal offsets, and also producing long, slender, scale-leaved rhizomes up to 15 cm long, and producing plantlets at their tips; plants in clonal colonies of many interconnected plants; [Coastal Plain, extending into the lower Piedmont of NJ, DE, MD, DC, VA, NC, and nc. SC]|
|..2 Plant only with a short, thick, fibrous-rooted rhizome that produces short basal offsets; plants in scattered populations of cespitose individuals; [Piedmont, Mountains, and Interior Low Plateau, extending eastwards into the Coastal Plain only in c. SC, GA, FL Panhandle, AL< and MS]|
|1 Leaves cauline, basal rosette lacking, the mid-stem leaves the largest; leaves entire (or with 1-2 teeth in S. tortifolius).|
....3 Leaves (2-) 4-8 cm long, 0.2-1.2 cm wide, linear to oblanceolate, 6-12× as long as wide, not twisted at the base (the leaf blade in a more-or-less horizontal plane); leaves glabrous (but with a ciliate margin), glandular-punctate; involucres glabrous
|....3 Leaves 1.5-4 cm long, 0.6-1.5 (-2.0) cm wide, obovate, 1.5-4× as long as wide, twisted at the base (bringing most of the leaf blade into a more-or-less vertical plane); leaves puberulent, glandular-punctate, and with prominent resin globules (at 10× magnification); involucres puberulent|