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.

Sorghastrum viride

HABIT Perennial. Culms erect; 125 cm long. Culm-internodes hollow. Culm-nodes constricted; pubescent. Leaf-sheaths longer than adjacent culm internode; glabrous on surface. Ligule an eciliate membrane; 3–4 mm long. Leaf-blades 20–40 cm long; 2–4 mm wide.

INFLORESCENCE Inflorescence a panicle with branches tipped by a raceme.

Panicle open; linear to lanceolate; 22 cm long. Panicle branches capillary.

Racemes bearing few fertile spikelets. Rhachis fragile at the nodes. Rhachis internodes filiform.

Spikelets in pairs. Fertile spikelets sessile; 1 in the cluster. Companion sterile spikelets pedicelled; 1 in the cluster. Pedicels filiform; ciliate.

STERILE SPIKELETS Companion sterile spikelets represented by barren pedicels.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets lanceolate; dorsally compressed; 5.5–6 mm long; falling entire; deciduous with accessory branch structures. Spikelet callus pilose; base obtuse.

GLUMES Glumes dissimilar; firmer than fertile lemma. Lower glume oblong; 1 length of spikelet; coriaceous; without keels; 9 -veined. Lower glume surface villous. Upper glume oblong; without keels; 5 -veined. Upper glume surface glabrous. Upper glume margins ciliolate.

FLORETS Basal sterile florets barren; without significant palea. Lemma of lower sterile floret oblong; 1 length of spikelet; hyaline; 2 -veined; ciliate on margins; fringed above. Fertile lemma oblong; 4–6 mm long; hyaline; without keel; 2 -veined. Lemma apex lobed; 2 -fid; awned; 1 -awned. Principal lemma awn from a sinus; geniculate; 15 mm long overall; with twisted column. Palea absent or minute.

FLOWER Anthers 3; 3 mm long.

DISTRIBUTION South America: Brazil and southern South America.

NOTES Andropogoneae. Swallen 2004.

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