Chasmanthium sessiliflorum

(Poir.) H.O. Yates
Common names: Longleaf chasmanthium
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.


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


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


Lower Taxa

J. Gabriel Sanchez-Ken +  and Lynn G. Clark +
(Poir.) H.O. Yates +
Longleaf chasmanthium +
Va. +, Okla. +, Miss. +, Tex. +, La. +, Mo. +, Ala. +, Tenn. +, N.C. +, S.C. +, Ark. +, Ga. +  and Fla. +
Uniola sessiliflora +  and Chasmanthium laxum subsp. sessiliflorum +
Chasmanthium sessiliflorum +
Chasmanthium +
species +