Hordeum murinum

HABIT Annual; caespitose. Culms 6–60 cm long; 3–5 -noded. Leaf-sheath oral hairs lacking. Leaf-sheath auricles falcate. Ligule an eciliate membrane; 0.5–1 mm long. Leaf-blades 2–20 cm long; 2–8 mm wide.

INFLORESCENCE Inflorescence composed of racemes.

Racemes 1; single; linear, or oblong; bilateral; 4–12 cm long. Rhachis fragile at the nodes; flattened. Spikelet packing broadside to rhachis. Rhachis internodes oblong; 3–3.5 mm long; falling with spikelet above.

Spikelets in threes. Fertile spikelets sessile; 1 in the cluster. Companion sterile spikelets pedicelled; 2 in the cluster. Pedicels oblong.

STERILE SPIKELETS Companion sterile spikelets well-developed; containing empty lemmas, or male; lanceolate; dorsally compressed; 7–11 mm long; as long as fertile; deciduous with the fertile. Companion sterile spikelet glumes subulate; 16–30 mm long; eciliate on margins, or ciliate on margins. Companion sterile spikelet lemmas 1; exserted from glumes; 7–11 mm long; 1-awned; with 10–40 mm long awn.

FERTILE SPIKELETS Spikelets comprising 1 fertile florets; without rhachilla extension. Spikelets lanceolate; dorsally compressed; 7–12 mm long; falling entire; deciduous with accessory branch structures.

GLUMES Glumes collateral; similar; gaping. Lower glume subulate; 25–30 mm long; 1 length of upper glume. Lower glume margins ciliate. Upper glume subulate; 25–30 mm long. Upper glume margins ciliate.

FLORETS Fertile lemma lanceolate; 7–12 mm long; coriaceous; without keel; 5 -veined. Lemma surface scabrous; rough above. Lemma apex acuminate; awned; 1 -awned. Principal lemma awn 18–50 mm long overall; limb scabrous.

FLOWER Anthers 3; 0.7–1.2 mm long. Ovary pubescent on apex.

FRUIT Caryopsis with adherent pericarp; ellipsoid; sulcate on hilar side; hairy at apex. Embryo 0.2 length of caryopsis. Hilum linear; 1 length of caryopsis.

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

NOTES Triticeae. CEH.

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