GrassBase - The Online World Grass Flora


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

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

Trisetum curvisetum

HABIT Perennial. Rhizomes short. Culms erect; 60–150 cm long; 0.7–1.7 mm diam. Lateral branches lacking, or sparse. Leaf-sheaths mostly shorter than adjacent culm internode; glabrous on surface, or pilose. Ligule an eciliate membrane; 1.1–2.3 mm long; entire, or erose; truncate. Leaf-blades 5–19 cm long; 1.5–8.5 mm wide. Leaf-blade surface pubescent; hairy adaxially. Leaf-blade apex acuminate.

INFLORESCENCE Inflorescence a panicle.

Panicle open; lanceolate, or pyramidal; 11–229 cm long; 2–15 cm wide. Primary panicle branches ascending; 3–5 -nate; 1–14 cm long. Panicle axis with lower internodes 2–10 cm long.

Spikelets solitary. Fertile spikelets pedicelled.

FERTILE SPIKELETS Spikelets comprising 2(–3) fertile florets; with a barren rhachilla extension. Spikelets oblong; laterally compressed; 3–5.2 mm long; breaking up at maturity; disarticulating below each fertile floret. Rhachilla internodes 1–1.8 mm long; pubescent.

GLUMES Glumes persistent; similar; shorter than spikelet; thinner than fertile lemma; shiny; gaping. Lower glume lanceolate; 1.8–2.5 mm long; 0.5–0.66 length of upper glume; membranous; 1-keeled; 1 -veined. Lower glume primary vein scaberulous. Lower glume lateral veins absent. Lower glume apex acuminate. Upper glume elliptic; 2.8–3.8 mm long; 1 length of adjacent fertile lemma; membranous; 1-keeled; 3 -veined. Upper glume primary vein smooth, or scaberulous. Upper glume lateral veins all falling short of apex. Upper glume apex acuminate.

FLORETS Fertile lemma lanceolate; 2.7–4.3 mm long; membranous; shiny; without keel; 5 -veined. Lemma lateral veins obscure. Lemma apex dentate; 2 -fid; with lobes 0.1–0.2 mm long; awned; 1 -awned. Principal lemma awn dorsal; arising 0.75 way up back of lemma; flexuous; 1.5–5.7 mm long overall. Palea gaping; 2.3–3.1 mm long; 0.5–0.8 length of lemma; hyaline. Palea keels scaberulous.

FLOWER Lodicules 2; oblong; 0.2–0.3 mm long; truncate. Anthers 3; 0.5–0.9 mm long.

FRUIT Caryopsis with adherent pericarp; 1.7–2.2 mm long. Embryo 0.2 length of caryopsis. Endosperm soft.

DISTRIBUTION North America: Mexico.

NOTES Aveneae. Morden & Valdes 2005.

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