Arrhenatherum elatius

HABIT Perennial; caespitose. Culms erect; 50–180 cm long; 3–5 -noded; not swollen at the base, or swollen at the base; forming moniliform corms. Culm-nodes glabrous, or pubescent. Leaf-sheaths without keel; smooth, or scaberulous; glabrous on surface, or pilose. Ligule an eciliate membrane; 0.5–2 mm long. Leaf-blades 10–40 cm long; 4–10 mm wide. Leaf-blade surface scaberulous; pilose; sparsely hairy; hairy adaxially.

INFLORESCENCE Inflorescence a panicle.

Panicle open; lanceolate, or oblong; equilateral, or nodding; 10–30 cm long.

Spikelets solitary. Fertile spikelets pedicelled. Pedicels filiform, or linear; 1–10 mm long.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; with a barren rhachilla extension. Spikelets oblong; laterally compressed; 7–11 mm long; breaking up at maturity; disarticulating below each fertile floret. Rhachilla internodes elongated below proximal fertile floret. Floret callus pilose.

GLUMES Glumes persistent; dissimilar; reaching apex of florets; thinner than fertile lemma; shiny; gaping. Lower glume lanceolate; (3–)4–6(–7) mm long; 0.6 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 ovate; 7–11 mm long; 0.9–1 length of adjacent fertile lemma; membranous; 1-keeled; 3 -veined. Upper glume primary vein scaberulous. Upper glume apex acute.

FLORETS Basal sterile florets male; with palea; attached to and deciduous with the fertile. Lemma of lower sterile floret ovate; 0.9 length of fertile lemma; chartaceous; much thinner above; 7 -veined; glabrous, or pilose; hairy below; dentate; 2 -fid; awned. Awn of lower sterile floret dorsal (on lower third of lemma); geniculate; 10–20 mm long. Fertile lemma obovate; 7–10 mm long; chartaceous; much thinner above; without keel; 7 -veined. Lemma surface glabrous, or pilose; hairy below. Lemma apex dentate; 2 -fid; muticous, or awned; 1 -awned. Principal lemma awn subapical; straight, or geniculate; 2–10.5 mm long overall. Palea keels ciliolate.

FLOWER Anthers 3; 3.7–5.2(–5.5) mm long. Ovary pubescent all over.

DISTRIBUTION Europe: northern, central, southwestern, southeastern, and eastern. Africa: north, Macaronesia, south, and western Indian ocean. Asia-temperate: Siberia, Soviet far east, Soviet Middle Asia, Caucasus, western Asia, and eastern Asia. Australasia: Australia and New Zealand. Pacific: north-central. North America: Subarctic, western Canada, eastern Canada, northwest USA, north-central USA, northeast USA, southwest USA, and southeast USA. South America: western South America, Brazil, and southern South America.

NOTES Aveneae. TAC.

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