Oat Brome

Appearance

Habit: Annual. Culms erect, or geniculately ascending; 5-40 cm long. Leaf-sheaths tubular for much of their length; pubescent. Ligule an eciliate membrane. Leaf-blades 2-10 cm long; 2-5 mm wide. Leaf-blade surface pubescent; hairy on both sides. Leaf-blade apex acuminate.

Inflorescences: Inflorescence a panicle. Panicle open; ovate; dense; 2-10 cm long; 1-2 cm wide. Primary panicle branches simple. Panicle branches scabrous. Spikelets solitary. Fertile spikelets pedicelled.

Spikelets: Spikelets comprising 6-16 fertile florets; with diminished florets at the apex. Spikelets elliptic; laterally compressed; 10-40 mm long; 4-10 mm wide; breaking up at maturity; disarticulating below each fertile floret.
Fertile: Spikelets comprising 6-16 fertile florets; with diminished florets at the apex. Spikelets elliptic; laterally compressed; 10-40 mm long; 4-10 mm wide; breaking up at maturity; disarticulating below each fertile floret.

Glume: Glumes persistent; dissimilar; shorter than spikelet. Lower glume lanceolate; 6-8 mm long; 0.8-0.9 length of upper glume; chartaceous; without keels; 3-5 -veined. Lower glume apex acute. Upper glume elliptic; 7-9 mm long; 0.7-0.8 length of adjacent fertile lemma; chartaceous; without keels; 7-9 -veined. Upper glume apex acute.

Florets: Fertile florets all alike, or with the lowest dissimilar. Lowest fertile lemma muticous. Fertile lemma elliptic; 8-12 mm long; chartaceous; much thinner on margins; without keel; 9-11 -veined. Lemma surface glabrous, or pubescent, or pilose, or villous. Lemma apex dentate; 2 -fid; awned; 3 -awned. Principal lemma awn dorsal; arising 0.66-0.75 way up back of lemma; curved; spreading; 5-15 mm long overall. Lateral lemma awns arising dorsally; shorter than principal. Apical sterile florets resembling fertile though underdeveloped.

Flowers: Lodicules 2; membranous. Anthers 3; 1.5 mm long. Ovary with a fleshy appendage above style insertion; pubescent on apex.

Fruits: Caryopsis with adherent pericarp; hairy at apex; apex fleshy. Hilum linear.

Distribution

Asia-temperate: Soviet Middle Asia, Caucasus, western Asia, Arabia, and China. Asia-tropical: India.

Status

Least Concern