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.

Avena barbata

HABIT Annual; culms solitary, or caespitose. Culms erect, or geniculately ascending; 30–100 cm long. Culm-nodes glabrous. Lateral branches lacking. Leaf-sheaths pilose. Ligule an eciliate membrane; 1–6 mm long; obtuse. Leaf-blades 6–30 cm long; 2–20 mm wide. Leaf-blade surface glabrous, or pilose; sparsely hairy.

INFLORESCENCE Inflorescence a panicle.

Panicle open; elliptic; effuse; nodding; 15–30(–50) cm long; 6–12 cm wide. Primary panicle branches 9–18 cm long. Panicle branches smooth, or scaberulous.

Spikelets pendulous; solitary. Fertile spikelets pedicelled. Pedicels filiform.

FERTILE SPIKELETS Spikelets comprising 2–3 fertile florets; with a barren rhachilla extension. Spikelets lanceolate; laterally compressed; 16–26 mm long; breaking up at maturity; disarticulating below each fertile floret. Rhachilla internodes pilose. Floret callus evident; bearded; obtuse. Floret callus hairs 2–3 mm long.

GLUMES Glumes persistent; similar; exceeding apex of florets; thinner than fertile lemma; gaping. Lower glume lanceolate; 16–26 mm long; 1 length of upper glume; membranous; without keels; 5(–7) -veined. Lower glume apex acuminate. Upper glume elliptic; 16–26 mm long; 1.3 length of adjacent fertile lemma; membranous; without keels; 7(–9) -veined. Upper glume apex acuminate.

FLORETS Fertile lemma lanceolate; 12–20 mm long; coriaceous; much thinner above; without keel; 9 -veined. Lemma surface scabrous; rough above; pilose; hairy below. Lemma apex dentate; 2 -fid; awned; 3 -awned. Principal lemma awn dorsal; arising 0.5 way up back of lemma; geniculate; 30–60 mm long overall; with twisted column. Lateral lemma awns arising on apex of lobes; 3–12 mm long; shorter than principal. Palea 10–18 mm long. Palea keels ciliolate.

FLOWER Anthers 3. Ovary pubescent all over.

FRUIT Caryopsis with adherent pericarp; sulcate on hilar side; hairy all over. Hilum linear.

DISTRIBUTION Europe: central, southwestern, southeastern, and eastern. Africa: north, Macaronesia, and south. Asia-temperate: Soviet Middle Asia, Caucasus, western Asia, and Arabia. Asia-tropical: India. Australasia: Australia and New Zealand. Pacific: north-central. North America: northwest USA, southwest USA, and Mexico. South America: western South America, Brazil, and southern South America.

NOTES Aveneae. Fl Turk 1993.

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