GrassBase - The Online World Grass Flora

Descriptions

W.D. Clayton, M. Vorontsova, K.T. Harman & H. Williamson

© Copyright The Board of Trustees, Royal Botanic Gardens, Kew.

Schizachyrium gracile

HABIT Perennial; caespitose. Culms erect; 20–80 cm long; wiry. Ligule an eciliate membrane. Leaf-blades filiform; terete; 4–30 cm long; 0.5–1 mm wide.

INFLORESCENCE Inflorescence composed of racemes; terminal and axillary.

Racemes 1; single; sinuous; 2–5 cm long. Rhachis fragile at the nodes; plumose on margins. Rhachis hairs 2–3 mm long. Rhachis internodes cuneate; 3–4 mm long. Rhachis internode tip transverse; cupuliform; with simple rim.

Spikelets spreading; in pairs. Fertile spikelets sessile; 1 in the cluster. Companion sterile spikelets pedicelled; 1 in the cluster. Pedicels filiform; curved; 3–4 mm long; plumose; with 2–3 mm long hairs.

STERILE SPIKELETS Companion sterile spikelets represented by single glumes; linear, or lanceolate; 2–3 mm long; shorter than fertile; deciduous with the fertile. Companion sterile spikelet glumes membranous; acute; awned; with 1–1.5 mm long awn.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets linear, or lanceolate; dorsally compressed; 3.5–5.5 mm long; falling entire; deciduous with accessory branch structures. Spikelet callus bearded; base obtuse; inserted. Spikelet callus hairs 2–3 mm long.

GLUMES Glumes dissimilar; exceeding apex of florets; firmer than fertile lemma. Lower glume lanceolate; 1 length of spikelet; cartilaginous; 2-keeled; keeled laterally. Lower glume intercarinal veins absent. Lower glume surface flat. Lower glume apex dentate; 2 -fid. Upper glume lanceolate; membranous; 1-keeled; 3 -veined. Upper glume apex acute; muticous.

FLORETS Basal sterile florets barren; without significant palea. Lemma of lower sterile floret lanceolate; hyaline; 2 -veined; acute. Fertile lemma oblong; hyaline; without keel; 1 -veined. Lemma apex lobed; 2 -fid; incised 0.33 of lemma length; awned; 1 -awned. Principal lemma awn from a sinus; geniculate; 10–15 mm long overall; with twisted column. Column of lemma awn glabrous. Palea absent or minute.

DISTRIBUTION North America: southeast USA and Mexico. South America: Mesoamericana and Caribbean.

NOTES Andropogoneae. WDC.

Please cite this publication as detailed in How to Cite Version: 3rd February 2016.