Apera spica-venti

HABIT Annual. Culms geniculately ascending, or decumbent; 20–100 cm long; 3–5 -noded. Ligule an eciliate membrane; 3–12 mm long. Leaf-blades 7–25 cm long; 3–10 mm wide. Leaf-blade surface scabrous; rough adaxially, or on both sides.

INFLORESCENCE Inflorescence a panicle.

Panicle open; ovate; effuse; 10–25 cm long; 3–15 cm wide. Primary panicle branches spreading; whorled at most nodes; profusely divided; 3–7 cm long.

Spikelets solitary. Fertile spikelets pedicelled. Pedicels 1–3 mm long; scaberulous.

FERTILE SPIKELETS Spikelets comprising 1 fertile florets; with a barren rhachilla extension. Spikelets oblong; laterally compressed; 2.5–3 mm long; breaking up at maturity; disarticulating below each fertile floret. Floret callus pubescent.

GLUMES Glumes persistent; similar; exceeding apex of florets; shiny. Lower glume lanceolate; 2.2–2.5 mm long; 0.75–0.9 length of upper glume; membranous; 1-keeled; 1 -veined. Lower glume primary vein scaberulous. Lower glume lateral veins absent. Lower glume apex acute. Upper glume lanceolate; 2.5–3 mm long; 1.1–1.2 length of adjacent fertile lemma; membranous; 1-keeled; 3 -veined. Upper glume primary vein scaberulous. Upper glume apex acute.

FLORETS Fertile lemma lanceolate; 2.1–2.8 mm long; membranous; without keel; 5 -veined. Lemma surface scaberulous; rough above. Lemma apex acute; awned; 1 -awned. Principal lemma awn subapical; flexuous; 5–10 mm long overall. Palea 0.9–1 length of lemma; 2 -veined.

FLOWER Anthers 3; 1–2 mm long.

FRUIT Caryopsis with adherent pericarp; ellipsoid. Endosperm liquid.

DISTRIBUTION Europe: northern, central, southwestern, southeastern, and eastern. Africa: north. Asia-temperate: Siberia, Soviet far east, Soviet Middle Asia, Caucasus, and western Asia. North America: north-central USA, northeast USA, and southeast USA.

NOTES Aveneae. FW 1995.

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