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 trichotoma

HABIT Perennial; caespitose. Culms 30–50 cm long. Ligule an eciliate membrane; obtuse. Leaf-blades filiform; convolute; 15–45 cm long; 0.2–0.5 mm wide; coriaceous.

INFLORESCENCE Inflorescence a panicle; deciduous as a whole.

Panicle open; ovate; effuse; 8–20 cm long. Panicle branches capillary.

Spikelets solitary. Fertile spikelets pedicelled.

FERTILE SPIKELETS Spikelets comprising 1 fertile florets; without rhachilla extension. Spikelets lanceolate; subterete; 4–8.5 mm long; breaking up at maturity; disarticulating below each fertile floret. Floret callus evident; pilose; acute. Floret callus hairs 0.5 length of lemma.

GLUMES Glumes persistent; similar; exceeding apex of florets; thinner than fertile lemma. Lower glume lanceolate; 4–8.5 mm long; 1 length of upper glume; hyaline; without keels; 3 -veined. Lower glume surface scabrous. Lower glume apex attenuate. Upper glume lanceolate; 4–8.5 mm long; 2.5–3.5 length of adjacent fertile lemma; hyaline; without keels; 3 -veined. Upper glume surface scabrous; rough on veins. Upper glume apex attenuate.

FLORETS Fertile lemma oblate; laterally compressed; 1.5–2.5 mm long; coriaceous; keeled; lightly keeled. Lemma surface tuberculate. Lemma margins convolute; covering most of palea. Lemma apex truncate; surmounted by a ring of hairs (obscure); awned; 1 -awned. Principal lemma awn eccentric; geniculate; 15–32 mm long overall; with twisted column; persistent, or deciduous. Column of lemma awn glabrous. Palea 0.5 length of lemma; hyaline; 0 -veined; without keels.

FLOWER Anthers 3; 1–1.5 mm long.

FRUIT Caryopsis with adherent pericarp; oblong; 1.2 mm long; dark brown.

DISTRIBUTION Europe: southwestern and southeastern. Africa: Macaronesia and south. Australasia: Australia and New Zealand. South America: Brazil and southern South America.

NOTES Stipeae. WDC.

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