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Key to Dichanthelium, Key A: Plants densely tufted, often cushion-forming; leaves basally disposed, the blades ascending or spreading-ascending,
not forming a distinct rosette of basal leaves shorter than the culm leaves; autumnal culms branching basally or from the lower nodes

Poaceae

Dichanthelium

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1 Spikelets 2.4-4.5 mm long.
  2 Nodes, internodes, and sheaths glabrous; blades 4-13 cm long, 5-8 mm wide, the surfaces smooth, glabrous; spikelets 2.4-2.9 mm long, glabrous; not known to produce axillary (autumnal) inflorescences
  2 Nodes bearded or otherwise pubescent; internodes and sheaths variously pubescent to glabrate; blades 6-35 cm long, 2-6 mm wide, one or both surfaces scabrous and often pubescent; spikelets 1.7-4.5 mm long, glabrous or pubescent; plants produce axillary (autumnal) inflorescences.
    3 Spikelets 2.8-3.8 (-4.5) mm long, the second glume and sterile lemma pointed or beaked and extended beyond the summit of the fertile lemma; first glume 1.2-2 mm long
    3 Spikelets 1.7-2.8 mm long, the second glume and sterile lemma blunt or broadly pointed, not extending beyond the summit of the fertile lemma; first glume 0.7-1.2 mm long
      4 Fresh plants light green to blue-green; leaf sheaths usually pilose; ligule of largest culm leaves 3-6× as wide as long; culm blades to 35 cm long, usually pilose on the upper surface
      4 Fresh plants darker green; leaf sheaths usually glabrous; ligule of largest culm leaves usually > 6× as wide as long; culm blades to 15 cm long, usually glabrate to glabrous on the upper surface
1 Spikelets 0.9-2.3 mm long.
        5 Longer blades > 6 cm; if only 6 cm, then sheaths, especially the lower, retrorsely long-pilose (D. laxiflorum).
          6 Spikelets 1.2-1.5 mm long, glabrous
          6 Spikelets (1.4-) 1.7-2.3 (-2.8) mm long, pubescent.
             7 Longer blades 10-35 cm long, 2-6 mm wide; sheaths glabrous to variously pilose, but not conspicuously retrorsely long-pilose; nodes variously pubescent to glabrate; spikelets 1.7-2.3 (-2.8) mm long
               8 Fresh plants light green to blue-green; leaf sheaths usually pilose; ligule of largest culm leaves 3-6× as wide as long; culm blades to 35 cm long, usually pilose on the upper surface
               8 Fresh plants darker green; leaf sheaths usually glabrous; ligule of largest culm leaves usually > 6× as wide as long; culm blades to 15 cm long, usually glabrate to glabrous on the upper surface
             7 Longer blades 6-18 cm long, 7-12 mm wide; sheaths conspicuously retrorsely long-pilose; nodes bearded with retrorse or spreading hairs; spikelets (1.4-) 1.9-2.3 (-2.5) mm long
        5 Longer blades 1.5-6 cm; sheaths glabrous or pubescent, but not retrorsely long-pilose.
                 9 Blades 1-3 mm wide, glabrous, eciliate or basally ciliate; spikelets 0.9-1.2 (-1.4) mm long.
                   10 Spikelets pubescent, 1.2-1.4 mm long; blades involute, often falcate, 2.5-6 cm long; [endemic to c. and s. FL scrub]
                   10 Spikelets glabrous, 0.9-1.2 mm long; blades flat, not falcate, 1.5-4 (-5) cm long; [wet sites, VA s. to FL, w. to e. LA]
                 9 Blades 3-8 mm wide; spikelets 1.1-2.1 mm long (or if < 1.5 mm long, then blades either pubescent on one or both surfaces or ciliate to the apex).
                     11 Spikelets pubescent, 1.5-2.1 mm long; blade surfaces glabrous
                     11 Spikelets glabrous, 1.1-1.8 mm long; blade surfaces pubescent or glabrous.
                       12 Blades glabrous, or sparsely pilose only near the adaxial base; spikelets 1.4-1.8 mm long
                       12 Blades pilose, at least abaxially; spikelets 1.1-1.6 mm long

Key to Dichanthelium, Key D: Spikelets 2.1-3.2 mm long, larger culm blades < 13 mm wide,
at least the lower culm nodes bearded with a usually spreading-ascending collar of dense and/or longish hairs

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1 Ligule with a dense ring of short hairs 0.5-1 mm long, and behind it a ring of longer hairs 1-5 (-8) mm long called the pseudoligule (see introduction for discussion of the so-called double ligule).
  2 Culm bases hard, thickened, corm-like; plants producing basal branches instead of rosettes, the branches ultimately producing the largest leaves, 4-13 cm long and 4-11 mm wide; vernal spikelets 2.3-2.7 mm long, 1.2-1.5 mm wide, autumnal spikelets 2.6-2.9 mm long, 1.0-1.1 mm wide; spikelets basally attenuate, the glumes attached 0.2-0.4 mm below expanding base of upper glume and lower lemma; [currently known only from sand ridges in peninsular FL]
  2 Plants without this combination of characters.
    3 Culms > 100 cm long; node pubescence densely retrorse; larger blades 12-20 cm long; spikelets acute; vernal spikelets 1.9-2.3 mm long, slightly < 2× as long as wide; autumnal spikelets 2.2-2.5 mm long, > 2× as long as wide
    3 Culms < 100 cm long (rarely longer); node pubescence various; larger blades 3-12 cm long; spikelets rounded to blunt, < 2× as long as wide.
      4 Plants velvety-pubescent throughout; nodes retrorsely bearded; internode pubescence retrorse to spreading; blades usually ciliate above base as well as basally; mature vernal panicles 3-7 cm long, 2-5 cm wide, about 2/3 as wide as long
      4 Plants densely pubescent to glabrate, but lacking velvety pubescence; nodes with spreading to ascending pubescence (sometimes retrorse in D. villosissimum); internode pubescence ascending, appressed, or spreading; blades ciliate only at base (sometimes appearing ciliate laterally in D. ovale var. ovale); mature vernal panicles 4-10 cm long, nearly or equally as wide.
        5 Lower internodes with retrorse or spreading hairs to 3+ mm long; blade adaxial surface pilose with hairs to 4+ mm long, these appressed and angled away from the leaf axis; spikelets 2.1-2.5 mm long
        5 Lower internodes pilose with (spreading-) ascending to appressed hairs, or nearly glabrous; blade adaxial surface sparsely appressed-pubescent to glabrate; spikelets 2.1-3.1 mm long.
          6 Spikelets 2.1-2.6 mm long; lower culm blades usually sparsely appressed-pubescent on both surfaces, eciliate or ciliate at the base only
          6 Spikelets 2.5-3.1 mm long; lower culm blades usually glabrous adaxially except for long hairs at or near the margin (appearing ciliate), appressed-pubescent abaxially
1 Ligule a single structure, without a pseudoligule.
             7 Culm bases hard, thickened, corm-like; plants producing basal branches instead of rosettes, the branches ultimately producing the largest leaves, 4-13 cm long and 4-11 mm wide; vernal spikelets 2.3-2.7 mm long, 1.2-1.5 mm wide, autumnal spikelets 2.6-2.9 mm long, 1.0-1.1 mm wide; spikelets basally attenuate, the glumes attached 0.2-0.4 mm below expanding base of upper glume and lower lemma; [currently known only from dry sand ridges in peninsular FL]
             7 Plants without this combination of characters.
               8 Ligule 2-5 mm long, ciliate
               8 Ligule < 2 mm long, ciliate or membranous.
                 9 Ligule a stramineous to light brown membrane, with or without terminal cilia; peduncle antrorsely scabrous but not hairy.
                   10 Panicle rachis smooth, pellucid-punctate; first glume 0.3-0.6 (-0.8 ) mm long, as broad as or broader than long, truncate to obtuse; larger leaves 10-25 cm long, 8-15 mm wide; ligule 0.5-1.3 mm long; lowest elongate culm internode > 2 mm in diameter; lowest nodes usually glabrous or pubescent
                   10 Panicle rachis scabrous or smooth, not pellucid-punctate; first glume 0.5-1.1 mm long, longer than wide, rounded to acute; larger leaves 3.5-12 cm long, 3-9 mm wide; ligule 0.1-0.6 mm long; lowest elongate culm internode < 2 mm in diameter; lowest nodes retrorsely bearded or glabrous.
                     11 Lowest nodes usually retrorsely bearded; ligules (0.1-) 0.3-0.6 mm long; largest vernal blades 7-12 cm long, (4.5-) 6-9 mm wide; panicle peduncle scabrous; spikelets ovate-lanceolate, acute, 2.0-2.4 mm long; first glume lanceolate, blunt to acute; fertile lemma smooth
                     11 Lowest nodes usually glabrous; ligules 0.1-0.2 (-0.3) mm long; largest vernal blades 3.5-7 cm long, 3-6 mm wide; panicle peduncle smooth; spikelets elliptic, blunt to acute, 1.6-2.2 mm long; first glume ovate to rotund, rounded to acute; fertile lemma papillose
                 9 Ligule entirely of white hairs; peduncle variously hairy or glabrous, but not antrorsely scabrous.
                       12 Culms with a viscid band below the retrorsely bearded nodes; internodes, sheaths, and blades velvety-pubescent
                       12 Culms without a viscid band below the retrorsely, spreading, or antrorsely bearded nodes; internodes and sheaths not velvety-pubescent, blades velvety-pubescent in some.
                          13 Basal as well as cauline blades linear, 5-15 cm long,; 1-4 mm wide, 30× or more as long as wide; spikelets 2.8-3.8 (-4.5) mm long
                          13 Blades < 15× as long as wide (if > 15×, then spikelets 1.9-2.5 mm long and sheaths retrorsely pilose in D. laxiflorum).
                            14 Blades (15-) 20× or more as long as wide, increasing in length upwards on culm; blade adaxial surface (weakly-) strongly scabrous; sheaths glabrous; second glume and sterile lemma exceeding fertile lemma
                            14 Blades < 15× as long as wide, similar or more often decreasing in size upwards on culm (if increasing, then sheaths strongly retrorsely pilose in D. laxiflorum); blade adaxial surface smooth to moderately scabrous; second glume and sterile lemma shorter than to exceeding fertile lemma.
                              15 Nodes retrorsely bearded; larger vernal leaves 7-15 mm wide.
                                16 Sheaths retrorsely pilose with hairs 2-3 mm long; basal leaves usually numerous, ascending, similar in size and shape to the culm leaves; culms branching only at the base in autumnal phase
                                16 Sheaths glabrous or pilose (if pilose, then hairs not both retrorse and 2-3 mm long); basal leaves rosette-forming, usually much shorter than culm leaves; culms branching above base in autumnal phase.
                                  17 Plants rarely > 1 m in length; lower internodes glabrous to sparsely hairy; vernal cauline leaves 3-7; spikelets 1.8-2.8 mm long, elliptic to lance-ovate, blunt to acute, glabrous or pubescent
                                  17 Plants often > 1 m in length; lowest internodes moderately to densely villous; vernal cauline leaves 6-15; spikelets 1.8-2.2 mm long, obovoid to broadly ellipsoid, rounded to blunt, pubescent
                              15 Nodes spreading to antrorsely bearded; larger vernal leaves 3-10 mm wide.
                                    18 Culm internodes glabrous to sparsely pilose; culm nodes bearded with long retrorse hairs; blade surfaces glabrous to velvety-pubescent
                                    18 Culm internodes, at least the lower, strigose, pilose, or villous; culm nodes bearded with ascending or spreading hairs; blade surfaces glabrous or variously hairy.
                                       19 Lower nodes bearded with erect-ascending, soft, and long hairs; mid-culm blades usually 20× or more as long as wide.
                                         20 Spikelets (3.0-) 3.2-3.8 mm long, fusiform, pointed at summit, attenuate at base, with both glumes attached 0.3-0.5 mm below sterile lemma, the autumnal spikelets 3.5-3.8 mm long; larger vernal blades 3-6 mm wide, the lower and mid-culm blades of similar width; autumnal blades involute
                                         20 Spikelets 1.8-3.1 mm long, obovate, blunt, and the base not attenuate except in D. arenicoloides with autumnal spikelets 2.3-3.1 mm long; larger vernal blades 2-8 mm wide, the lower usually wider and often shorter than mid-culm blades; autumnal blades involute or flat.
                                           21 Longest vernal blades to 16 cm, widest vernal blades 4-8 mm, usually longitudinally wrinkled; vernal and autumnal spikelets 2.3-3.1 mm long; autumnal blades flat, the larger to 9 cm × 2-4 mm
                                           21 Longest vernal blades to 6 (D. aciculare) or 12 (D. arenicoloides) cm long, 2-5 mm wide, not noticeably wrinkled; vernal spikelets 1.5-2.8 mm long, autumnal spikelets either 1.5-2.3 (D. aciculare) or 2.3-3.1 (D. arenicoloides); autumnal blades involute, the larger to 6 cm × 1.5 mm.
                                             22 Longest vernal blades to 6 (-8) cm, widest vernal blades 2-5 mm; vernal and autumnal spikelets 1.7-2.3 mm long, blunt, not attenuate, the glumes attached <0.2 mm below sterile lemma; first glumes 0.6-0.9 mm long; larger autumnal blades to 3 cm by 1 mm
                                             22 Longest vernal blades to 12 cm, widest vernal blades 3-4 (-5) mm; vernal spikelets 2.1-2.8 mm long; autumnal spikelets 2.3-3.1 mm long, pointed, attenuate, the glumes attached 0.3-0.5 mm below sterile lemma; first glumes 0.7-1.5 mm long; larger autumnal blades to 6 cm by 1.5 mm
                                       19 Lower and often mid-culm nodes bearded with spreading, stiffish, and short-to-long hairs; mid-culm blades usually 15× or less as long as wide.
                                               23 Blades stiff, often longitudinally ribbed, at least the lower villous or strongly pilose on the abaxial surface, and pilose to hirsute on the adaxial surface, at least proximally.
                                                 24 Spikelets 2.3-3.0 mm long; ligule < 1 mm long; mid-culm blades 4-8 mm wide
                                                 24 Spikelets 1.7-2.0 (-2.3) mm long; ligule 1-2.5 mm long; mid-culm leaves 2-5 mm wide
                                               23 Blades not noticeably stiff nor longitudinally ribbed, pubescent or strigose underneath, glabrous above or with a few long hairs near the base.
                                                    25 Spikelet bases strongly attenuate, apices blunt to beaked; first glume (2/5-) ½-2/3 (-4/5) as long as spikelet, attached 0.3-0.5 (-0.7) mm belong expansion of second glume and sterile lemma; larger vernal blades 3-6 (-7) mm wide
                                                    25 Spikelet bases not noticeably attenuate, apices rounded to obtuse; first glume < ½ as long as spikelet, attached < 0.3 mm below expansion of second glume and sterile lemma; larger vernal blades 5-12 mm wide.
                                                      26 Culms 50-140 cm long; lowest internodes usually purplish; leaf sheaths often viscid-spotted; leaf blades glabrous abaxially, glabrous and scabrous adaxially; spikelets 1.8-2.2 mm long
                                                      26 Culms 15-60 cm long; lowest internodes usually olive- or bluish-green; leaf sheaths not viscid-spotted; leaf blades appressed-pubescent abaxially, glabrous and smooth to appressed pubescent adaxially; spikelets 2.1-3.1 mm long.
                                                        27 Spikelets 2.1-2.6 mm long; lower culm blades usually sparsely appressed-pubescent on both surfaces, eciliate or ciliate at the base only
                                                        27 Spikelets 2.5-3.1 mm long; lower culm blades usually glabrous adaxially except for long hairs at or near the margin (appearing ciliate), appressed-pubescent abaxially

Key to Dichanthelium, Key F: Spikelets 0.8-2.0 mm long, lower culm internodes variously hairy

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1 Longer hairs of ligule 2-5 mm long.
  2 Ligule with a distinct ring of short hairs in front of the long hairs.
    3 Peduncle, panicle axis, and sheaths puberulent with hairs 0.1 mm long; larger blades 3-6 cm long, 3-5 mm wide; spikelets 1.3-1.7 mm long
    3 Peduncle, panicle axis, and sheaths pubescent with hairs more than 0.1 mm long; larger blades 12-20 cm long, 7-9 mm wide; spikelets 1.9-2.3 mm long
  2 Ligule without a distinct ring of short hairs in front of the long hairs.
      4 Culms > 100 cm long; node pubescence densely retrorse; larger blades 12-20 cm long; vernal spikelets 1.9-2.3 mm long, nearly 2× as long as wide; autumnal spikelets 2.2-2.5 mm long, > 2× as long as wide
      4 Culms < 100 cm long (-rarely longer); node pubescence various; larger blades 3-12 cm long; spikelets (1.0-) 1.1-2.0 mm long, less than 2 × as long as wide, rounded to blunt.
        5 Blades of mid-culm leaves lanceolate, thin or firm but not stiff, length and width various, less than 15× as long as wide
        5 Blades of mid-culm leaves linear or narrowly lanceolate, stiff, acuminate, often involute, 4-10 cm long, 2-5 mm wide, about 15-20× as long as wide
1 Longer hairs of ligule < 2 mm long.
          6 Culm leaves basally crowded, ascending, usually matted or cushion-forming, larger than the mid and upper culm blades.
             7 Sheaths conspicuously retrorsely long-pilose; longer blades 6-18 cm long and 7-12 mm wide; spikelets (1.4-) 1.9-2.3 (-2.5) mm long
             7 Sheaths variously pubescent or glabrous, but not conspicuously retrorsely long-pilose; longer blades 2-6 cm long and 1-8 mm wide; spikelets 0.9-2.1 mm long.
               8 Leaf blades 1-4 mm wide, glabrous, the margins eciliate or basally ciliate; spikelets 0.9-1.5 mm long, glabrous; autumnal form branched from lower and mid nodes as well as from basal nodes.
                 9 Leaf blades 1.5-4 (-5) cm long; spikelets 0.9-1.2 (-1.4) mm long
                 9 Leaf blades 4-12 (-20) cm long, some at least 7 cm long; spikelets 1.2-1.5 mm long
               8 Leaf blades 2-10 mm wide, pubescent or glabrous, the margins coarsely papillose-ciliate throughout; spikelets 1.1-2.1 mm long, glabrous or pubescent; autumnal form branched from basal nodes only.
                   10 Spikelets pubescent, 1.5-2.1 mm long; blade surfaces glabrous
                   10 Spikelets glabrous, 1.1-1.8 mm long; blade surfaces pubescent or glabrous.
                     11 Leaf blades glabrous, or sparsely pilose only near the adaxial base; spikelets 1.4-2.1 mm long
                     11 Leaf blades pilose, at least abaxially; spikelets 1.1-1.6 mm long
          6 Culm leaves not basally crowded, the lowest leaves spreading and rosette-forming, usually smaller than the culm leaves.
                       12 Blades progressively longer upwards on culm, the larger 9-20 cm long and 3-8 mm wide, (15-) 20 × or more as long as wide, firm but not stiff, not longitudinally grooved or wrinkled; blade adaxial surface (weakly-) strongly scabrous; sheaths glabrous; second glume and sterile lemma exceeding fertile lemma
                       12 Blades similar or more often decreasing in size upwards on culm; if 15 × or more as long as wide, then larger blades 4-10 cm long and 2-5 mm wide, stiff and longitudinally grooved or wrinkled (sect. Angustifolia); blade adaxial surface smooth to moderately scabrous; sheaths glabrous or pilose; second glume and sterile lemma shorter than to equaling fertile lemma.
                          13 Blades of mid-culm leaves linear or narrowly lanceolate, stiff, acuminate, often involute, 4-10 cm long, 2-5 mm wide, about 15-20× as long as wide.
                            14 Ligule less than 1 mm long; nodes glabrous to sparsely pubescent, not bearded; blades glabrous (lowest sometimes sparsely pilose); autumnal blades involute
                            14 Ligule (1-) 1.5-2 (-2.5) mm long; nodes bearded with spreading-ascending hairs; blades moderately hirsute; autumnal blades flat
                          13 Blades of mid-culm leaves lanceolate to lance-elliptic, thin or firm but not stiff, length and width various, < 15× as long as wide.
                              15 Internodes crisp-puberulent.
                                16 Ligule 0.7-1.5 mm long; first glume acute; spikelets elliptic when viewed dorsally, biconvex or elliptic when viewed laterally, not strongly nerved
                                16 Ligule < 0.5 mm long; first glume obtuse to truncate; spikelets obovate when viewed dorsally, plano-convex when viewed laterally, strongly nerved.
                                  17 Spikelets (1.8-) 1.9-2.2 (-2.5) mm long; first glume 0.8-1.2 mm long; lower culm blades 2-8 mm wide
                                  17 Spikelets 1.5-1.8 mm long; first glume 0.5-0.8 mm long; lower culm blades 2-5 mm wide
                              15 Internodes variously hairy but not crisp-puberulent.
                                    18 Culms (55-) 70-140 cm long; nodes retrorsely bearded; vernal cauline leaves 6-15; blades 6-15 cm long, 8-13 mm wide, glabrous
                                    18 Culms < 60 cm long; nodes not retrorsely bearded; vernal cauline leaves 2-7; blades to 14 cm long and 17 mm wide, glabrous or pubescent.
                                       19 Internodes (sparsely-) moderately to densely pubescent to pilose; ligule 1-5 mm long; blade margins either weakly ciliate, papillose-ciliate basally only, or eciliate, lacking a white-beige cartilaginous edge 0.2 mm wide.
                                         20 Larger mid-culm blades 4-7 cm long, 4-7 mm wide, glabrous to sparsely pubescent adaxially; ligule 1-5 mm long; spikelets 1.1-1.5 mm long
                                         20 Larger mid-culm blades 3-6 cm long, 3-5 mm wide, long-pilose adaxially; ligule often with a ring of hairs < 1 mm and scattered longer hairs to 4 mm; spikelets 1.3-1.7 mm long
                                       19 Internodes sparsely pilose; ligule < 1 mm long; blade margins various.
                                           21 Blades 5-14 cm by 5-17 mm, basally truncate to cordate, margins only ciliate basally if at all, without a white-beige margin up to 0.2 mm wide
                                           21 Blades 1.5-6 (8) cm by 2-8 mm, basally narrowed to rounded, blade margins either coarsely papillose-ciliate throughout or glabrous with a white-beige cartilaginous edge about 0.2 mm wide.
                                             22 Blades with white-beige cartilaginous margins 0.2 mm wide; spikelets 1.4-1.7 mm long; autumnal form branching from middle and upper nodes
                                             22 Blade margins coarsely papillose-ciliate throughout; spikelets 1.1-2.1 mm long; autumnal form branching from the base.
                                               23 Spikelets pubescent, 1.5-2.1 mm long; blade surfaces glabrous
                                               23 Spikelets glabrous, 1.1-1.8 mm long; blade surfaces pubescent or glabrous.
                                                 24 Blades glabrous, or sparsely pilose only near the adaxial base; spikelets 1.4-1.8 mm long
                                                 24 Blades pilose; spikelets 1.1-1.6 mm long

Key to Dichanthelium, Key G: Spikelets 0.8-2.0 mm long, lower culm internodes glabrous

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1 Ligule 1-5 mm long.
  2 Ligule (1.5-) 2-5 mm long; sheaths glabrous to variously pubescent; internodes glabrous or pubescent; nodes glabrous, or bearded with ascending, spreading, or tangled hairs; leaves 3-10 cm long, 3-10 mm wide; spikelets 0.8-1.9 mm long
  2 Ligule 1-2 mm long; sheaths sparsely to moderately spreading short-pilose; internodes glabrous; nodes retrorsely bearded; leaves 1-4 cm long, 2-5 mm wide; spikelets 1.2-1.4 mm long
1 Ligule < 1 mm long.
    3 Basal leaves rosette-forming, usually much smaller than the culm leaves, not matted or cushion-forming; culms branching at the mid and upper nodes in age.
      4 Blades of mid-culm leaves typically long and acuminate, linear or narrowly lanceolate, usually 10-20× as long as wide, only 2-5 mm wide when < 8 cm long.
        5 Vernal leaf blades 9-20 cm long, the larger usually 5-8 mm wide, becoming longer upwards on the culm, (weakly-) strongly scabrous on the adaxial surface; spikelets sparsely pubescent to glabrous
        5 Vernal leaf blades to 11(14) cm long, those on the upper culm smaller or similar in size to those below, the adaxial surface not scabrous except sometimes on the margins (or scabrous in D. neuranthum with leaves no more than 5 mm wide and spikelets moderately glandular papillose-pubescent).
          6 Spikelets (glandular-) papillose-pubescent; blades 1-3 (-5) mm wide; first glume 0.8-1.0 mm long; culms to 4 dm tall
          6 Spikelets glabrous; blades 3-8 mm wide; first glume 0.3-1.1 mm long; culms to 10 dm tall.
             7 Leaves 3-8 mm wide; panicle (8-) 20-40 mm wide; first glume 0.6-1.1 mm long, blunt to acute
             7 Leaves 3-5.5 mm wide; panicle 2-5 mm wide; first glume 0.3-0.4 mm long, truncate to obtuse
      4 Blades of mid-culm leaves lanceolate, mostly 10× or less as long as wide, usually 7 mm or more wide when as much as 8 cm long.
               8 Spikelets elliptic, oblong, or obovate; lower culm blades 3-12 (-15) mm wide, thin, tapered to the base; plants often freely branching in age, becoming top-heavy with a mass of fascicled, reduced leafy branches and inflorescences
               8 Spikelets broadly elliptic to suborbicular; lower culm blades 6-30 mm wide, broad and cordate to subcordate at the base; plants sparingly branched in age, not becoming top-heavy with fascicled, reduced leafy branches and inflorescences.
                 9 Leaf blades not noticeably thick; ligules ciliate, to 0.8 mm long; spikelets 1.8-2.6 mm long, elliptic, obtuse to subacute; first glumes 0.5-1.0 mm long
                 9 Leaf blades thickish; ligule obsolete or with cilia < 0.8 mm long; spikelets 0.9-1.9 mm long, obovoid to spherical, rounded; first glumes 0.2-0.8 mm long.
                   10 Spikelets 0.9-1.2 mm long; longer blades 6-8 cm long, erect to erect-ascending
                   10 Spikelets 1.2-1.9 mm long; longer blades 8-20 cm long, ascending or the uppermost erect.
                     11 Mid-culm blades to 25 cm long, 14-30 mm wide, the uppermost 10-15+ cm long; vernal panicles to 20 cm long, often less than half as wide as long; spikelets 1.3-1.6 (-1.7)
                     11 Mid-culm blades to 10 cm long, 5-11 (-14) mm wide, the uppermost 3-9 cm long; vernal panicles to 14 cm long, usually more than half as wide as long; spikelets (1.4-) 1.5-1.8 mm long
    3 Basal leaves similar to or larger than the mid and upper culm leaves, often matted or cushion-forming; culms branching at the base (also at mid and upper nodes in D. chamaelonche vars. and D. dichotomum var. glabrifolium).
                       12 Longer blades > 6 cm; if only 6 cm, then sheaths retrorsely long-pilose (D. laxiflorum).
                          13 Spikelets 1.2-1.5 mm long, glabrous
                          13 Spikelets 1.7-2.3 (-2.8) mm long, pubescent.
                            14 Longer blades 6-18 cm long by 7-12 mm wide; sheaths conspicuously retrorsely long-pilose; nodes bearded with retrorse or spreading hairs; spikelets (1.4-) 1.9-2.3 (-2.5) mm long
                            14 Longer blades 10-35 cm long by 2-6 mm wide; sheaths glabrous to variously pilose, but not conspicuously retrorsely long-pilose; nodes variously pubescent to glabrate; spikelets 1.7-2.3 (-2.8) mm long.
                              15 Fresh plants light green to blue-green; leaf sheaths usually pilose; ligule of largest culm leaves 3-6× as wide as long; culm blades to 35 cm long, usually pilose on the upper surface
                              15 Fresh plants darker green; leaf sheaths usually glabrous; ligule of largest culm leaves usually > 6× as wide as long; culm blades to 15 cm long, usually glabrate to glabrous on the upper surface
                       12 Longer blades 1.5-6 cm; sheaths glabrous or pubescent, but not retrorsely long-pilose.
                                16 Blades 1-3 mm wide, glabrous, eciliate or basally ciliate; spikelets 0.9-1.4 mm long.
                                  17 Spikelets pubescent, 1.2-1.4 mm long; blades involute, often falcate, 2.5-6 cm long; [endemic to c. and s. FL scrub]
                                  17 Spikelets glabrous, 0.9-1.2 mm long; blades flat, not falcate, 1.5-4 (-5) cm long; [wet sites, VA s. to FL, w. to e. LA]
                                16 Blades 3-8 mm wide; spikelets 1.1-2.1 mm long (if < 1.5 mm, then blades either pubescent on one or both surfaces or ciliate to the apex).
                                    18 Spikelets pubescent, 1.5-2.1 mm long; blade surfaces glabrous
                                    18 Spikelets glabrous, 1.1-1.8 mm long; blade surfaces pubescent or glabrous.
                                       19 Blades glabrous, or sparsely pilose only near the adaxial base; spikelets 1.4-2.1 mm long
                                       19 Blades pilose, at least abaxially; spikelets 1.1-1.6 mm long