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1 Leaves petiolate or sessile, none of them clasping the stem. |
2 All or most of the largest leaves sharply serrate; apex of the leaves acute to attenuate. |
3 Axis of raceme with at least some of the hairs 0.13-0.25 mm long; nutlets 2-3 mm long; flowering Apr to early Jul (or later if burned) |
3 Axis of raceme with hairs < 0.1 mm long; nutlets usually 3-4 mm long; flowering Jul-Oct. |
4 Perennating buds usually borne directly on the primary rhizome or at the ends of short, vertical secondary rhizomes (horizontal secondary rhizomes usually lacking), the plant thus forming clumps; nonglandular trichomes of the raceme axis < 0.1 (-0.13) mm long; sterile floral bracts usually present below lowest flowers; flowers (16-) 18-37 mm long |
4 Perennating buds usually borne at the ends of elongate, horizontal, secondary rhizomes, the plant thus forming clonal patches; nonglandular trichomes of the raceme axis frequently 0.15-(-0.20) mm long; sterile floral bracts usually not present below lowest flowers; flowers (13-) 14-28 mm long |
2 Half or more of the larger leaves bluntly toothed to entire; apex of the leaves obtuse, or acute to attenuate. |
5 Calyx and rachis of the inflorescence bearing stalked glands (visible at 10× magnification or greater); nutlets 1.7-2.0 mm long, usually warty over the surface |
5 Calyx and rachis lacking stalked glands; nutlets 2.0-3.6 mm long, smooth. |
6 Uppermost pair of leaves below the terminal raceme often no larger than the floral bracts, the next pair of leaves down the stem 0.4-3.2 cm long, generally 0.1-0.3× as long as the internode above |
6 Uppermost pair of leaves below the terminal raceme usually considerably larger than the floral bracts, the next pair of leaves down the stem (1.5-) 2.0-12.8 cm long and 0.3-2× as long as the internode above. |
7 Leaves (some of them) present at or after anthesis usually petiolate, the petioles often > 2 cm long, the petiolate leaves typically the lowest and among the largest leaves present |
7 Leaves present at or after anthesis usually sessile (rarely a few petiolate, but these with petioles < 2 cm long and the petiolate leaves usually not among the largest leaves present) |
1 Leaves, 1 or more of them, conspicuously or inconspicuously clasping the stem. |
8 Perennating buds borne directly on the primary rhizome or at the ends of short, vertical secondary rhizomes (horizontal secondary rhizomes lacking), the plant thus forming clumps |
9 Most or all of the larger leaves sharply serrate; larger leaves usually < 2.5 cm wide and > 5× as long as wide |
9 Most or all of the larger leaves bluntly serrate to entire; larger leaves usually > 3 cm wide or < 5× as long as wide. |
10 Raceme axis densely tomentose, the hairs mostly 0.2-0.3 mm long; calyx lobes at anthesis generally 2-3 mm long, attenuate or cuspidate |
10 Raceme axis puberulent to pubescent, the hairs almost all < 0.2 mm long; calyx lobes at anthesis generally 1-2 mm long, mostly acute |
8 Perennating buds borne at the ends of elongate, horizontal, secondary rhizomes, the plant thus forming clonal patches. |
11 Calyx and inflorescence rachis bearing stalked glands as well as nonglandular hairs; leaves mainly 2-3× as long as wide |
11 Calyx and rachis with nonglandular hairs only; leaves mostly > 3.5× as long as wide. |
12 Flowers 22-35 mm long; larger stem leaves acute to attenuate at the tip; axis of raceme with at least some of the hairs 0.13-0.25 mm long; larger stem leaves mostly sharply serrate |
12 Flowers smaller, or most of the leaves obtuse at the tip, or hairs of the raceme axis < 0.13 mm long; larger stem leaves bluntly toothed to entire. |
13 Flowering calyx tube (1-) 2-4 mm long; flowers < 20 mm long |
13 Flowering calyx tube 3-7 (-8) mm long; flowers usually > 20 mm long. |
14 Uppermost pair of leaves below the terminal raceme usually considerably larger than the floral bracts, the next pair of leaves down the stem (1.5-) 2.0-12.8 cm long and 0.3-2× as long as the internode above; principal stem leaves usually widest at or below the middle of the blade |
14 Uppermost pair of leaves below the terminal raceme often no larger than the floral bracts, the next pair of leaves down the stem 0.4-3.2 cm long, generally 0.1-0.3× as long as the internode above; principal stem leaves usually widest at or above the middle of the blade |