Dichanthelium strigosum

(Muhl. ex Elliott) Freckmann
Common names: Cushion-tufted panicgrass
Synonyms: Panicum strigosum
Treatment appears in FNA Volume 25. Treatment on page 446.
Revision as of 03:04, 30 July 2020 by imported>Volume Importer
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Plants densely cespitose. Basal rosettes poorly differentiated; blades 1-5 cm, lanceolate, grading into the cauline blades. Culms 5-45 cm, slender, erect or spreading; from a dense tuft of predominantly basal leaves, lower internodes short, upper 3-5 internodes elongate; nodes glabrous or bearded; internodes glabrous or pilose; fall phase with spreading culms and branches arising from near the bases forming a dense, flat tuft. Cauline leaves 2-4; lower cauline sheaths longer than the internodes, mostly glabrous or pilose with ascending hairs, margins finely ciliate; ligules 0.2-2 mm, at low magnification appearing to membranous and ciliate, at high magnification evidently of hairs that coherent at the base; blades 1.5-6 cm long, 3-8 mm wide, lanceolate, glabrous or softly pilose, margins with prominent papillose-based cilia, at least basally. Primary panicles short to long-exserted; rachises and branches often pilose. Spikelets 1.1-2.1 mm, obovoid to broadly ellipsoid, glabrous or pubescent, hairs not papillose-based. Lower glumes 1/3 - 1/2 as long as the spikelets, acute to obtuse; upper florets 0.8-1.7 mm, ellipsoid, subacute.

Distribution

Puerto Rico, Va., Ga., Tex., La., Ala., Tenn., N.C., S.C., Miss., Fla.

Discussion

Dichanthelium strigosum extends from the southeastern Flora region south into Mexico, the Caribbean, and into northern South America.

The primary panicles are briefly open-pollinated in April or May; the secondary panicles, which are produced from May through November, are cleistogamous. The three subspecies are mostly sympatric and sometimes grow together, with occasional intergradation.

Selected References

None.

Key

1 Spikelets pubescent, broadly ellipsoid, 1.6-2.1 mm long; lower glumes about 1/2 as long as the spikelets; blades glabrous Dichanthelium strigosum subsp. leucoblepharis
1 Spikelets glabrous, obovoid, 1.1-1.8 mm long; lower glumes about 1/3 as long as the spikelets; blades pilose or glabrous. > 2
2 Blades pilose; spikelets 1.1-1.6 mm long Dichanthelium strigosum subsp. strigosum
2 Blades glabrous or sparsely pilose near the base; spikelets 1.4-1.8 mm long Dichanthelium strigosum subsp. glabrescens

"usually distinctly longer and narrower" is not a number."decumbent" is not a number.

... more about "Dichanthelium strigosum"
rounded +  and attenuate +
anatomy +  and kranz +
Mary E. Barkworth +
(Muhl. ex Elliott) Freckmann +
1 (?) +  and 3 (?) +
keeled +  and rounded +
pseudopetiolate +  and branching +
divergent +  and parallel +
coherent +
intravaginal +, extravaginal +, branching +  and basal +
swelling +
membranous +
disarticulating +  and pseudopetiolate +
non-radiate +  and radiate +
green +  and yellowish +
separable +
distinct +
1.5 cm15 mm <br />0.015 m <br /> (6 cm60 mm <br />0.06 m <br />) +
pilose +  and glabrous +
lanceolate +
1 cm10 mm <br />0.01 m <br /> (5 cm50 mm <br />0.05 m <br />) +
0.3 cm3 mm <br />0.003 m <br /> (0.8 cm8 mm <br />0.008 m <br />) +
spikelike +
0 cm0 mm <br />0 m <br /> (1 cm10 mm <br />0.01 m <br />) +
not developed +
terete +  and compressed +
papillose-based +
sometimes longer +
Cushion-tufted panicgrass +
branching +  and hollow +
decumbent +  and sprawling +
slender +
5 cm50 mm <br />0.05 m <br /> (55 cm550 mm <br />0.55 m <br />) +
Puerto Rico +, Va. +, Ga. +, Tex. +, La. +, Ala. +, Tenn. +, N.C. +, S.C. +, Miss. +  and Fla. +
capillary +
germination +
pistillate +  and staminate +
sometimes longer +
compressed +  and terete +
shorter or longer +
subtending +
unequal +
membranous +
not papillose-based +
uncinate +
0.1 cm1 mm <br />0.001 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
membranous +
Oval (?) +  and Round (?) +
bracteate +  and ebracteate +
solid +  and hollow +
pilose +  and glabrous +
spreading +  and erect +
5 cm50 mm <br />0.05 m <br /> (45 cm450 mm <br />0.45 m <br />) +
coriaceous +
0.02 cm0.2 mm <br />2.0e-4 m <br /> (0.2 cm2 mm <br />0.002 m <br />) +
membranous +
inconspicuous +
pilose +  and glabrous +
1/3 +  and 1/2 +
acute +  and obtuse +
complex +  and simple +
concealed +  and prominent +
bearded +  and glabrous +
2 +  and 1 +
subterranean +
dry +  and fleshy +
in triplets +  and paired +
pubescent +  and glabrous +
1 +  and 60 +
unisexual +  and bisexual +
obovoid +  and broadly ellipsoid +
0.11 cm1.1 mm <br />0.0011 m <br /> (0.21 cm2.1 mm <br />0.0021 m <br />) +
1 +  and 3 +
fused +  and free +
2 +  and 3 +
dome--shaped +  and triangular +
Panicum strigosum +
Dichanthelium strigosum +
Dichanthelium sect. Strigosa +
species +
membranous +
subacute +  and ellipsoid +
0.08 cm0.8 mm <br />8.0e-4 m <br /> (0.17 cm1.7 mm <br />0.0017 m <br />) +
chartaceous-indurate +
plant +  and cespitose +
aquatic +  and terrestrial +
dioecious +, monoecious +  and synoecious +