Chasmanthium sessiliflorum

(Poir.) H.O. Yates
Common names: Longleaf chasmanthium
Endemic
Synonyms: Uniola sessiliflora Chasmanthium laxum subsp. sessiliflorum
Treatment appears in FNA Volume 25. Treatment on page 346.

Culms 60-150 cm, (1) 2-3.5 mm thick at the nodes, unbranched, leafy for 40% of their height. Sheaths pilose; collars pilose; ligules 0.2-0.3 mm, entire; blades (15) 20-50 cm long, 4.5-9.5 (15) mm wide, linear-lanceolate, sparsely pilose adaxially. Panicles (9) 20-70 cm, contracted or open, erect; branches tightly appressed or ascending to strongly divergent; axils of panicle branches glabrous or scabridulous at the edges; pedicels 0.3-2.5 (5) mm. Spikelets 4-10 mm long, 6-9 mm wide, with 4-7 (8) florets, lower 1 (2) florets sterile, fertile florets divergent to 80°. Lower glumes 1.2-2.7 mm, 3-5-veined; upper glumes 1.4-2.2 mm, 3-5-veined; calluses glabrous; fertile lemmas 3.5-5.9 mm, usually curved or irregularly contorted, 7-9-veined, keels not winged, apices scabridulous; paleas 2.8-4 mm; anthers (0.8) 1.3-1.6 mm, varying in length within a spikelet. Caryopses 2-2.5 mm, exposed at maturity. 2n = 24.

Distribution

Va., Okla., Miss., Tex., La., Mo., Ala., Tenn., N.C., S.C., Ark., Ga., Fla.

Discussion

Chasmanthium sessiliflorum grows in rich woods, meadows, and swamps, especially on the coastal plain. It grows throughout most of the southeastern United States.

Selected References

None.

Lower Taxa

None.

"varying" is not a number."leafy" is not a number."decumbent" is not a number.

0.8 cm8 mm <br />0.008 m <br /> (?) +
0.13 cm1.3 mm <br />0.0013 m <br /> (0.16 cm1.6 mm <br />0.0016 m <br />) +
scabridulous +
Acuminate (?) +  and Acute (?) +
J. Gabriel Sanchez-Ken +  and Lynn G. Clark +
(Poir.) H.O. Yates +
1 (?) +  and 3 (?) +
keeled +  and rounded +
pseudopetiolate +  and branching +
divergent +  and parallel +
intravaginal +, extravaginal +, branching +  and basal +
swelling +
not pseudopetiolate +
20 cm200 mm <br />0.2 m <br /> (50 cm500 mm <br />0.5 m <br />) +
linear-lanceolate +
4.5mm;9.5mm +
scabridulous +
ascending;appressed +
spikelike +
brown +  and reddish-black or black +
compressed +
0.2 cm2 mm <br />0.002 m <br /> (0.25 cm2.5 mm <br />0.0025 m <br />) +
fusoidlike +
Longleaf chasmanthium +
ascending +  and erect +
60 cm600 mm <br />0.6 m <br /> (150 cm1,500 mm <br />1.5 m <br />) +
not woody +
0.2 cm2 mm <br />0.002 m <br /> (0.35 cm3.5 mm <br />0.0035 m <br />) +
Va. +, Okla. +, Miss. +, Tex. +, La. +, Mo. +, Ala. +, Tenn. +, N.C. +, S.C. +, Ark. +, Ga. +  and Fla. +
less +  and 1/3 +
large +  and small +
capillary +
pistillate +  and staminate +
sometimes longer +
basal +  and distal +
rudimentary +
4 +  and 7 +
fertile +  and sterile +
round +  and compressed +
reduced +
(2)3-9-veined +
subtending +
acute +  and acuminate +
subequal +
membranous +
uncinate +
subbasal +  and basal +
hollow +  and solid +
compressed-keeled +
0.35 cm3.5 mm <br />0.0035 m <br /> (0.59 cm5.9 mm <br />0.0059 m <br />) +
0.02 cm0.2 mm <br />2.0e-4 m <br /> (0.03 cm0.3 mm <br />3.0e-4 m <br />) +
membranous +
inconspicuous +
0.12 cm1.2 mm <br />0.0012 m <br /> (0.27 cm2.7 mm <br />0.0027 m <br />) +
concealed +  and prominent +
2 +  and 1 +
well-developed +
2-keeled +  and gibbous +
0.28 cm2.8 mm <br />0.0028 m <br /> (0.4 cm4 mm <br />0.004 m <br />) +
9 cm90 mm <br />0.09 m <br /> (?) +
20 cm200 mm <br />0.2 m <br /> (70 cm700 mm <br />0.7 m <br />) +
5 cm50 mm <br />0.05 m <br /> (?) +
0.03 cm0.3 mm <br />3.0e-4 m <br /> (0.25 cm2.5 mm <br />0.0025 m <br />) +
dry +  and fleshy +
staminate +, pistillate +, subsessile +, pedicellate +  and solitary +
0.4 cm4 mm <br />0.004 m <br /> (1 cm10 mm <br />0.01 m <br />) +
1 +  and 60 +
compressed +
0.4 cm4 mm <br />0.004 m <br /> (5 cm50 mm <br />0.05 m <br />) +
6mm +  and 9mm +
free +  and fused +
triangular +  and dome--shaped +
Uniola sessiliflora +  and Chasmanthium laxum subsp. sessiliflorum +
Chasmanthium sessiliflorum +
Chasmanthium +
species +
membranous +
0.14 cm1.4 mm <br />0.0014 m <br /> (0.22 cm2.2 mm <br />0.0022 m <br />) +
plant +, colonial +  and cespitose +
aquatic +  and terrestrial +
pilose +, scabrous +  and glabrous +