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.

Nassella rhizomata

HABIT Perennial; caespitose. Rhizomes elongated. Culms 50–105 cm long; 3–5 -noded. Leaf-sheaths smooth; glabrous on surface, or puberulous; outer margin hairy. Leaf-sheath oral hairs ciliate; 0.5–1 mm long. Ligule an eciliate membrane; 0.2–0.3 mm long; erose; truncate. Leaf-blades flat, or convolute; 4–35 cm long; 1–4.5 mm wide. Leaf-blade surface pubescent. Leaf-blade apex attenuate.

INFLORESCENCE Inflorescence a panicle.

Panicle open; oblong; 7–40 cm long.

Spikelets solitary. Fertile spikelets pedicelled.

FERTILE SPIKELETS Spikelets comprising 1 fertile florets; without rhachilla extension. Spikelets lanceolate; subterete; 6.3–10 mm long; breaking up at maturity; disarticulating below each fertile floret. Floret callus elongated; curved; 1–1.5 mm long; pubescent; pungent.

GLUMES Glumes persistent; similar; exceeding apex of florets; thinner than fertile lemma. Lower glume linear; 6.3–10 mm long; 1.1 length of upper glume; membranous; without keels; 3 -veined. Lower glume surface smooth, or asperulous; rough on veins. Lower glume apex acuminate. Upper glume linear; 5.5–8.5 mm long; 1.4–1.5 length of adjacent fertile lemma; membranous; without keels; 3 -veined. Upper glume surface smooth, or asperulous; rough on veins. Upper glume apex acuminate.

FLORETS Fertile lemma lanceolate; subterete; 4.5–5.5 mm long; coriaceous; dark brown; without keel; 5 -veined. Lemma surface papillose; pubescent. Lemma margins convolute; covering most of palea. Lemma apex with a membranous corona and surmounted by a ring of hairs; with this appendage 0.3–0.5 mm long; awned; 1 -awned. Principal lemma awn bigeniculate; 34–48 mm long overall; with twisted column. Column of lemma awn pubescent. Palea 0.5–1.3 mm long; 0 -veined; without keels. Palea surface glabrous, or pilose; hairy on back. Palea apex erose.

FLOWER Lodicules 2. Anthers 1; 0.3–0.5 mm long; yellow. Staminodes present (2 of them). Stigmas 2. Ovary glabrous.

FRUIT Caryopsis with adherent pericarp; linear; 2.5–3 mm long. Hilum linear.

DISTRIBUTION South America: Brazil.

NOTES Stipeae. H.L-W 1996.

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