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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
1Ligule 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).
2Culm 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]
3 Culms > 100 cm long; nodepubescence 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
5 Lower internodes with retrorse or spreading hairs to 3+ mm long; bladeadaxial surface pilose with hairs to 4+ mm long, these appressed and angled away from the leaf axis; spikelets 2.1-2.5 mm long
1Ligule a single structure, without a pseudoligule.
7Culm 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]
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.
13Basal 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
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); bladeadaxial surface smooth to moderately scabrous; second glume and sterilelemma 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
17 Plants often > 1 m in length; lowest internodes moderately to densely villous; vernalcauline leaves 6-15; spikelets 1.8-2.2 mm long, obovoid to broadly ellipsoid, rounded to blunt, pubescent
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 sterilelemma, 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 sterilelemma; 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 sterilelemma; first glumes 0.7-1.5 mm long; larger autumnal blades to 6 cm by 1.5 mm
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 appressedpubescent 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
2Ligule without a distinct ring of short hairs in front of the long hairs.
4 Culms > 100 cm long; nodepubescence 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); nodepubescence 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
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
6Culm 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; bladeadaxial surface (weakly-) strongly scabrous; sheaths glabrous; second glume and sterilelemma 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); bladeadaxial surface smooth to moderately scabrous; sheaths glabrous or pilose; second glume and sterilelemma 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.
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
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
1 Internodes glabrous (sometimes lowest internodes sparsely to moderately pubescent).
2Ligule 1-2 mm long; sheaths sparsely to moderately spreading short-pilose; nodes retrorsely bearded; leaves 1-4 cm long, 2-5 mm wide; spikelets 1.2-1.4 mm long
3 Leaf bladebasalcilia usually conspicuous; larger vernal blades 6-10 cm by 6-10 mm; internodes, especially lower, sometimes pilose; spikelets obovoid; plant often yellowish-green (orange-brown in age)
3 Leaf bladebasalcilia usually inconspicuous or absent; larger vernal blades 2.5-10 cm long, 2-9 mm wide; all internodes glabrous (rarely the lowest sparsely pilose); spikelets ellipsoid; plant often green to purplish.
4 Spikelets (0.9-) 1.1-1.5 mm long, moderately densely to densely puberulent, most hairs < 0.1 mm long; panicles 3-8 cm long, usually more than ½ as wide as long; larger blades 2.5-8 cm long
4 Spikelets (1.3-) 1.4-1.9 mm long, (glabrous-) sparsely to moderately pubescent, most hairs > 0.1 mm long; panicles 4-12 cm long, usually less than ½ as wide as long; larger blades 7-10 cm long
5Peduncle, panicleaxis, and/or sheaths of vernal culms puberulent with hairs 0.1 mm long, sometimes also pubescent with longer hairs, but never grayish-villous; larger leaf blades 2-7 cm long, 2-7 mm wide.
6 Spikelets 0.8-1.1 mm long; mid-culm leaf blades 2-4.5 cm long, 2-5 mm wide; sheaths sparsely puberulent to glabrous, lacking papillose-based longer hairs
7 Larger mid-culm leaf 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
8 Culms > 100 cm long; nodepubescence 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
8 Culms < 100 cm long (-rarely longer); nodepubescence various; larger blades 4-12 cm long, < 15 × as long as wide; spikelets (1.0-) 1.1-2.0 mm long, less than 2× as long as wide, rounded to blunt.
9 Sheaths and internodes of vernal culms gray-villous with a dense, tangled, or matted mixture of slender hairs 2-4 mm long, variously ascending, spreading, and retrorse, papillose or non-papillose, often with shorter hairs beneath; leaf blades velvety-pubescent on abaxial surface, the margins ciliate (or appearing ciliate) for half or more their length.
10 Plants drying light green to yellow-green; culms usually < 60 cm long; lower internodes rarely more than 1.3 mm in diameter; panicles usually < 8 cm long; primary branching at most nodes before maturation of vernalpanicle, longer branches often exceeding the culm
10 Plants drying olive-green, sometimes purplish; culms usually > 60 cm long; lower internodes usually > 2 mm in diameter; panicles usually 9-11 cm long; primary branching sparingly from middle nodes after maturation of vernalpanicle, longer branches not exceeding culm
13 Leaf blades 5-12 cm long, 6-12 mm wide; spikelets 1.5-2.0 mm long; peduncle, panicleaxis, and sheaths variously pilose, but lacking puberulent hairs 0.1 mm long
13 Leaf blades 3-7 cm long, 3-7 mm wide; spikelets 1.1-1.7 mm long; puberulent hairs 0.1 mm long often present on peduncle, panicleaxis, or sheaths.
14 Larger mid-culm leaf blades 4-7 cm long, 4-7 mm wide, glabrous to sparsely pubescent adaxially; ligule 1-5 mm long, the hairs of one series; spikelets 1.1-1.5 mm long
14 Larger mid-culm leaf blades 3-6 cm long, 3-5 mm wide, long-pilose adaxially; ligule often with a short series of hairs <1 mm long in front of a series with hairs to 4 mm long; spikelets 1.3-1.7 mm long