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1 Mid-stem leaves narrowed above the clasping base to an elongate petiolar portion (1/8-1/2 of the blade length) which flares abruptly into an ovate to lanceolate upper portion 10-55 mm wide; stem slightly to strongly zigzag in the upper portion |
1 Mid-stem leaves linear, lanceolate; stem usually straight (lacking bends alternating at the nodes). |
..2 Phyllaries appressed (or in some species the outer slightly spreading); plants 0.5-8.5 (12) dm tall. |
....3 Leaves linear, 1.5-5 (-9) mm wide; [NJ, PA, WV, and OH northwards] |
....3 Leaves linear to broadly lanceolate, 8-45 mm wide; [collectively widespread]. |
......4 Lower stems hirsute, upper stems hirsutulous; [Buck Creek Serpentine Barren, Clay County, NC] |
......4 Lower stems glabrous and glaucous; upper stems glabrous or sparsely hirsute; [collectively widespread]. |
........5 Leaves basally disposed, the largest basal and persistent; largest leaves linear, to 20 cm × 2.5 cm, avg. 10× as long as wide; leaf margins often strongly scabrous; [mainly of the Coastal Plain, of SC and GA west to AR and TX] |
........5 Leaves cauline, the largest on the stem; largest leaves narrowly to broadly lanceolate, avg. < 9× as long as wide; leaf margins usually only slightly scabrous; [mainly of inland provinces, of NS west to MB, south to GA, Panhandle FL, MS, LA, and OK]. |
..........6 Larger leaves > 5× as long as wide, rarely > 2.5 cm wide, the bases slightly clasping; [NY and KY south to GA, Panhandle FL (Jackson County), and MS] |
..........6 Larger leaves < 5× as long as wide, often > 2.5 cm wide, the bases strongly clasping; [NS west to MB, south to GA, LA, and OK] |
..2 Phyllaries slightly to distinctly spreading, loose, or recurved-squarrose, some at least foliose; plants (4-) 8-30 dm tall. |
............ 7 Upper leaf surfaces glabrous or soft-pubescent (puberulent). |
............ ..8 Leaf margins revolute; flowering array branches ascending and densely leafy, the leaves overtopping the heads; [inland provinces] |
............ ..8 Leaf margins planar; flowering array branches spreading to ascending, with small, bracteal leaves; [mainly Costal Plain, SC northwards]. |
............ ....9 Leaves linear, > 10× as long as wide; leaf bases only subclasping |
............ ....9 Leaves lanceolate, 6-10× as long as wide; leaf bases clasping |
............ 7 Upper leaf surfaces scabrous. |
............ ......10 Stem leaves cuneate or rounded to an only slightly clasping base |
............ ......10 Stem leaves strongly auriculate-clasping. |
............ ........11 Upper and lower leaf surfaces nearly the same color; upper stem leaves smaller in size than the midstem leaves |
............ ........11 Upper and lower leaf surfaces distinctly different in color (the lower pale green, the upper dark green); upper stem leaves (on branches leading to heads) equal or nearly so in size to mid-stem leaves |
............ ..........12 Plants to 6 dm tall; {other characters}; [nw. NC] |
............ ..........12 Plants 10-30 dm tall; {other characters}; [widespread] |