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 leve

HABIT Perennial; caespitose; clumped densely. Culms 20–50 cm long. Leaf-sheath oral hairs ciliate. Ligule an eciliate membrane; 3–7 mm long; 1–1.5 mm long on basal shoots; acute. Leaf-blades tortuous; 3–7 cm long; 2–4 mm wide; 0.2–1.2 cm long at summit of culm; glaucous; pruinose. Leaf-blade venation without layer of subepidermal sclerenchyma masking vein striation. Leaf-blade surface ungrooved.

INFLORESCENCE Inflorescence a panicle; comprising 6–8 fertile spikelets.

Panicle open; linear, or oblong; 6–13 cm long; bearing few spikelets. Primary panicle branches 1–2 -nate; 0.5–1.5 cm long. Panicle branches smooth.

Spikelets solitary. Fertile spikelets pedicelled.

FERTILE SPIKELETS Spikelets comprising 5–7 fertile florets; with diminished florets at the apex. Spikelets oblong; laterally compressed; 14–18 mm long; breaking up at maturity; disarticulating below each fertile floret. Rhachilla internodes 2 mm long; pilose; with 1.5–2.5 mm long hairs. Floret callus pilose.

GLUMES Glumes persistent; similar; shorter than spikelet; thinner than fertile lemma. Lower glume elliptic; 9–11 mm long; 0.75 length of upper glume; membranous; 1-keeled; 3 -veined. Lower glume apex acute. Upper glume elliptic; 12–14 mm long; 1.2–1.3 length of adjacent fertile lemma; membranous; 1-keeled; 3 -veined. Upper glume apex acute.

FLORETS Fertile lemma elliptic; widest at 0.75 of its length from base; 9–12 mm long; cartilaginous; without keel; 5–7 -veined. Lemma apex dentate; 2 -fid; obtuse; awned; 1 -awned. Principal lemma awn dorsal; arising 0.5 way up back of lemma; geniculate; flat below; 15–20 mm long overall; with twisted column. Palea keels ciliolate. Apical sterile florets resembling fertile though underdeveloped.

FLOWER Anthers 3. Ovary pubescent on apex.

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

DISTRIBUTION Europe: southwestern.

NOTES Aveneae. Fl Eur 1995.

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