GrassBase - The Online World Grass Flora

Descriptions

W.D. Clayton, M. Vorontsova, K.T. Harman & H. Williamson

© Copyright The Board of Trustees, Royal Botanic Gardens, Kew.

Helictotrichon pratense

HABIT Perennial; caespitose. Butt sheaths dark brown. Culms erect; 30–85 cm long; 1–2 -noded. Leaves mostly basal. Leaf-sheaths glabrous on surface. Ligule an eciliate membrane; 2–4.5(–6) mm long. Leaf-blades 4–30 cm long; 1–5 mm wide. Leaf-blade venation distinct. Leaf-blade surface glabrous. Leaf-blade margins scaberulous.

INFLORESCENCE Inflorescence a panicle.

Panicle contracted; lanceolate; equilateral; 4–18 cm long. Primary panicle branches 1–2 -nate; 1–3.5 cm long; bearing 1–2 fertile spikelets on each lower branch. Panicle branches scaberulous.

Spikelets solitary. Fertile spikelets pedicelled.

FERTILE SPIKELETS Spikelets comprising 3–5(–8) fertile florets; with a barren rhachilla extension. Spikelets oblong; laterally compressed; 14–28 mm long; breaking up at maturity; disarticulating below each fertile floret. Rhachilla internodes pubescent; hairy all along but hairs longer above; with 1–2 mm long hairs. Floret callus pilose.

GLUMES Glumes persistent; similar; shorter than spikelet; thinner than fertile lemma; shiny. Lower glume lanceolate; 9.5–16 mm long; 0.7–0.8 length of upper glume; membranous; 1-keeled; 3 -veined. Lower glume apex acute. Upper glume lanceolate; 12–20 mm long; 1.1–1.2 length of adjacent fertile lemma; membranous; with hyaline margins; 1-keeled; 3 -veined. Upper glume apex acute.

FLORETS Fertile lemma oblong; 10–17(–20) mm long; chartaceous, or cartilaginous; without keel; 5 -veined. Lemma surface scaberulous; rough above. Lemma apex dentate; 2 -fid; awned; 1 -awned. Principal lemma awn dorsal; arising 0.5–0.6 way up back of lemma; geniculate; 12–27 mm long overall; with twisted column. Palea 0.9–1 length of lemma. Palea keels ciliolate. Rhachilla extension 0.33–0.5 length of fertile floret; pilose.

FLOWER Anthers 3; 4–7 mm long. Ovary pubescent on apex.

FRUIT Caryopsis with adherent pericarp; hairy at apex. Hilum linear.

DISTRIBUTION Europe: northern, central, southwestern, southeastern, and eastern. Africa: north. Asia-temperate: western Asia. Asia-tropical: India.

NOTES Aveneae. TAC.

Please cite this publication as detailed in How to Cite Version: 27th January 2014.