Avena fatua

HABIT Annual. Culms erect, or geniculately ascending; 30–150 cm long; 3–5 -noded. Leaves cauline. Ligule an eciliate membrane; 4–6 mm long. Leaf-blades 10–45 cm long; 3–15 mm wide. Leaf-blade surface scaberulous.

INFLORESCENCE Inflorescence a panicle.

Panicle open; pyramidal; nodding; 10–40 cm long; 5–20 cm wide. Primary panicle branches drooping. Panicle branches scaberulous.

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

FERTILE SPIKELETS Spikelets comprising 2–3 fertile florets; with a barren rhachilla extension. Spikelets cuneate; laterally compressed; 18–28 mm long; breaking up at maturity; disarticulating below each fertile floret. Floret callus evident; bearded; obtuse; disarticulating obliquely. Floret callus hairs 0.2 length of lemma.

GLUMES Glumes persistent; similar; exceeding apex of florets; thinner than fertile lemma; gaping. Lower glume lanceolate; 18–28 mm long; 1 length of upper glume; membranous; without keels; 7–11 -veined. Lower glume apex acuminate. Upper glume lanceolate; 18–28 mm long; 1.2–1.4 length of adjacent fertile lemma; membranous; without keels; 7–11 -veined. Upper glume apex acuminate.

FLORETS Fertile lemma lanceolate; 14–20 mm long; coriaceous; much thinner above; dark brown; without keel; 7–9 -veined. Lemma surface pilose; hairy below. Lemma apex dentate; 2–4 -fid; with irregular lobes; awned; 1 -awned. Principal lemma awn dorsal; arising 0.5 way up back of lemma; geniculate; 25–40 mm long overall; with twisted column. Palea keels ciliate.

FLOWER Anthers 3; 3 mm long. Ovary pubescent all over.

FRUIT Caryopsis with adherent pericarp; 6–8 mm long; hairy all over. Hilum linear.

DISTRIBUTION Europe: northern, central, southwestern, southeastern, and eastern. Africa: north, Macaronesia, northeast tropical, east tropical, southern tropical, and south. Asia-temperate: Siberia, Soviet far east, Soviet Middle Asia, Caucasus, western Asia, Arabia, China, Mongolia, and eastern Asia. Asia-tropical: India and Malesia. Australasia: Australia and New Zealand. Pacific: south-central, northwestern, and north-central. North America: Subarctic, western Canada, eastern Canada, northwest USA, north-central USA, northeast USA, southwest USA, south-central USA, and Mexico. South America: Mesoamericana, Caribbean, northern South America, western South America, Brazil, and southern South America. Antarctic: Subantarctic islands.

NOTES Aveneae. FTEA.

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