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.

Andropogon cordatus

HABIT Perennial. Rhizomes elongated. Culms erect; robust; 200–250 cm long. Ligule an eciliate membrane. Leaf-blade base amplexicaul. Leaf-blades 10–30 cm long; 15–22 mm wide. Leaf-blade surface glabrous. Leaf-blade apex acuminate.

INFLORESCENCE Synflorescence compound; linear; 30–90 cm long. Inflorescence composed of racemes; terminal and axillary; subtended by a spatheole. Spatheole linear; 4–6 cm long.

Racemes 2–3; paired, or digitate; 2–3.5 cm long. Rhachis fragile at the nodes; villous on margins. Rhachis hairs 2–3 mm long. Rhachis internodes linear. Rhachis internode tip transverse; cupuliform; with simple rim.

Spikelets ascending, or spreading; in pairs. Fertile spikelets sessile; 1 in the cluster. Companion sterile spikelets pedicelled; 1 in the cluster. Pedicels linear; villous.

STERILE SPIKELETS Companion sterile spikelets well-developed; containing empty lemmas, or male; linear; 4–6 mm long; as long as fertile; separately deciduous. Companion sterile spikelet glumes chartaceous; glabrous; acute; muticous. Companion sterile spikelet lemmas enclosed by glumes.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets lanceolate; dorsally compressed; 4–5 mm long; falling entire; deciduous with accessory branch structures. Spikelet callus glabrous; base obtuse; inserted.

GLUMES Glumes dissimilar; exceeding apex of florets; firmer than fertile lemma. Lower glume lanceolate; 1 length of spikelet; coriaceous; 2-keeled; keeled laterally. Lower glume intercarinal veins absent. Lower glume surface concave. Upper glume linear; coriaceous; 1-keeled. Upper glume muticous.

FLORETS Basal sterile florets barren; without significant palea. Lemma of lower sterile floret oblong; hyaline. Fertile lemma lanceolate; 4–5 mm long; hyaline; without keel. Lemma apex lobed; 2 -fid; awned; 1 -awned. Principal lemma awn from a sinus; geniculate; 15–18 mm long overall; with a straight or slightly twisted column. Column of lemma awn glabrous.

DISTRIBUTION South America: western South America.

NOTES Andropogoneae. Gr Bolivia 1997.

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