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.

Avena clauda

HABIT Annual; culms solitary, or caespitose. Culms erect, or geniculately ascending; 13–60 cm long. Culm-internodes glaucous. Lateral branches lacking. Leaf-sheaths glabrous on surface, or pilose. Ligule an eciliate membrane; 1.8–3 mm long; obtuse. Leaf-blades 3–10 cm long; 2–4 mm wide. Leaf-blade surface glabrous, or pilose.

INFLORESCENCE Inflorescence a panicle.

Panicle open; elliptic; nodding; 6–15 cm long; 4–6 cm wide.

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

FERTILE SPIKELETS Spikelets comprising 3–5 fertile florets; with a barren rhachilla extension. Spikelets lanceolate; laterally compressed; 18–25 mm long; breaking up at maturity; disarticulating below each fertile floret. Floret callus evident; bearded; obtuse; disarticulating obliquely. Floret callus hairs 4–4.5 mm long.

GLUMES Glumes persistent; similar; exceeding apex of florets; thinner than fertile lemma; gaping. Lower glume lanceolate; 11–15 mm long; 0.5–0.66 length of upper glume; membranous; without keels; 3–5 -veined. Lower glume apex acuminate. Upper glume elliptic; 20–25 mm long; 1–1.3 length of adjacent fertile lemma; membranous; without keels; 7 -veined. Upper glume apex acuminate.

FLORETS Fertile lemma lanceolate; 20 mm long; coriaceous; much thinner above; without keel; 7 -veined. Lemma surface glabrous, or pilose; hairy above. Lemma apex dentate; 2 -fid; awned; 3 -awned. Principal lemma awn dorsal; arising 0.33–0.5 way up back of lemma; geniculate; 30 mm long overall; with twisted column. Lateral lemma awns arising on apex of lobes; 7 mm long; shorter than principal. 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: southeastern. Africa: north. Asia-temperate: Soviet Middle Asia, Caucasus, and western Asia.

NOTES Aveneae. Fl Turk 1993.

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