Heteropogon triticeus

HABIT Perennial; caespitose. Culms erect; 100–160 cm long; 4–8 mm diam. Culm-internodes solid. Culm-nodes constricted; brown, or black. Lateral branches fastigiate. Leaves cauline. Leaf-sheaths keeled. Ligule an eciliate membrane; 1 mm long; membranous; truncate. Collar glabrous. Leaf-blades 20–80 cm long; 3–11 mm wide. Leaf-blade midrib evident. Leaf-blade surface ribbed; scaberulous. Leaf-blade margins ciliate; hairy at base. Leaf-blade apex attenuate.

INFLORESCENCE Inflorescence composed of racemes. Peduncle smooth.

Racemes 1; single; erect; 9–14 cm long; bearing 5–7(–10) fertile spikelets on each. Rhachis fragile at the nodes; glabrous on margins. Rhachis internodes cuneate; 0.5–1 mm long. Rhachis internode tip oblique.

Spikelets appressed; in pairs. Fertile spikelets sessile; 2 in the cluster. Companion sterile spikelets pedicelled; 1 in the cluster. Pedicels 0.5–1 mm long; 0.1 length of fertile spikelet; smooth.

STERILE SPIKELETS Basal sterile spikelets well-developed; 16–40 in number; subsessile and pedicelled; larger than fertile. Basal sterile spikelet glumes coriaceous; scabrous on margins; lower glume muticous.

Companion sterile spikelets well-developed; male; elliptic; asymmetrical; dorsally compressed; 21–25 mm long; longer than fertile; separately deciduous. Companion sterile spikelet callus linear; 2–3 mm long. Companion sterile spikelet glumes herbaceous, or coriaceous; eglandular; winged on margins; distinctly veined; smooth, or tuberculate; acute; muticous. Companion sterile spikelet lemmas 2; enclosed by glumes.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets linear; subterete; 13–15 mm long; falling entire; deciduous with accessory branch structures. Spikelet callus linear; 4.5–6 mm long; bearded; base pungent; attached obliquely. Spikelet callus hairs dark brown, or red; 0.3 length of spikelet.

GLUMES Glumes dissimilar; with lower wider than upper; exceeding apex of florets; firmer than fertile lemma. Lower glume linear; 1 length of spikelet; coriaceous; dark brown; without keels; 9 -veined. Lower glume surface grooved on either side of midvein; puberulous, or pubescent. Lower glume apex obtuse. Upper glume linear; symmetrical; coriaceous; with membranous margins; dark brown; without keels; winged on margins; 3 -veined. Upper glume surface puberulous, or pubescent. Upper glume muticous.

FLORETS Basal sterile florets barren; without significant palea. Lemma of lower sterile floret elliptic; 1 length of fertile lemma; hyaline; 0 -veined; without midvein; without lateral veins. Fertile lemma linear, or oblong; membranous; 3 -veined. Lemma apex entire; awned; 1 -awned. Principal lemma awn geniculate; 120–140 mm long overall; with twisted column. Column of lemma awn hirtellous. Palea absent or minute.

FLOWER Anthers 3; 8 mm long. Stigmas 2.

DISTRIBUTION Asia-temperate: China. Asia-tropical: India, Indo-China, Malesia, and Papuasia. Australasia: Australia.

NOTES Andropogoneae. TB.

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