Trisetum phleoides

HABIT Perennial; caespitose. Culms erect; 15–60 cm long. Culm-internodes distally pubescent. Leaf-sheaths pubescent. Ligule an eciliate membrane; 2–3.5 mm long. Leaf-blades 2–3 mm wide; stiff. Leaf-blade surface pubescent; hairy on both sides. Leaf-blade margins ciliate. Leaf-blade apex acute.

INFLORESCENCE Inflorescence a panicle.

Panicle spiciform; linear; 4–9 cm long. Panicle axis pubescent. Panicle branches pubescent.

Spikelets solitary. Fertile spikelets pedicelled. Pedicels pubescent.

FERTILE SPIKELETS Spikelets comprising 2–3 fertile florets; with a barren rhachilla extension. Spikelets oblong; laterally compressed; 6–7.5 mm long; breaking up at maturity; disarticulating below each fertile floret. Rhachilla internodes pilose. Floret callus pubescent. Floret callus hairs 0.5 mm long.

GLUMES Glumes persistent; similar; exceeding apex of florets; thinner than fertile lemma; shiny; gaping. Lower glume lanceolate; 4.5–7 mm long; 0.75 length of upper glume; membranous; 1-keeled; 1 -veined. Lower glume primary vein ciliate. Lower glume lateral veins absent, or distinct. Lower glume apex setaceously attenuate. Upper glume lanceolate; 6–7.5 mm long; 1.2–1.5 length of adjacent fertile lemma; membranous; 1-keeled; 3 -veined. Upper glume primary vein ciliate. Upper glume apex setaceously attenuate.

FLORETS Fertile lemma oblong; 4–6.5 mm long; membranous; shiny; keeled; 5 -veined. Lemma apex dentate; 2 -fid; awned; 3 -awned. Principal lemma awn dorsal; arising 0.66 way up back of lemma; geniculate; 5.5–6.5 mm long overall; with twisted column. Lateral lemma awns 0.5–1 mm long. Palea gaping; hyaline. Palea apex with excurrent keel veins.

FLOWER Lodicules 2; ciliate. Anthers 3; 1–1.3 mm long. Ovary glabrous.

FRUIT Caryopsis with adherent pericarp; 2–2.5 mm long. Hilum punctiform. Endosperm liquid.

DISTRIBUTION South America: southern South America.

NOTES Aveneae. Fl Pat 1995.

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