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.

Festuca azucarica

HABIT Perennial; caespitose; clumped densely. Cataphylls evident. Butt sheaths persistent and investing base of culm; with compacted dead sheaths. Basal innovations intravaginal. Culms erect; of moderate stature; straight; 50–100 cm long; 2 -noded; with 0.5–0.66 of their length below uppermost node; without nodal roots. Culm-internodes terete; smooth. Culm-nodes without exudate; glabrous. Lateral branches lacking. Leaves mostly basal; 0–1 per branch. Leaf-sheaths tight; unthickened at base; open for most of their length; without keel; striately veined; smooth. Ligule a ciliolate membrane; 1–1.5 mm long; membranous; white; entire; obtuse. Leaf-blade base symmetrical. Leaf-blades straight; filiform; conduplicate; elliptic in section; 20–35 cm long; 0.9–1.1 mm wide; coriaceous; stiff; dark green. Leaf-blade midrib indistinct. Leaf-blade venation indistinct; comprising 11–13 vascular bundles; with 9–11 inner ridges; with 12 subepidermal sclerenchyma strands; with subepidermal sclerenchyma strands similar in size; with subepidermal sclerenchyma attached to veins above and below; with continuous uniform subepidermal sclerenchyma layer on the underside. Leaf-blade surface glabrous, or hirsute; densely hairy; hairy adaxially. Leaf-blade margins smooth; glabrous. Leaf-blade apex obtuse.

INFLORESCENCE Inflorescence a panicle; with 1 peduncles per sheath. Peduncle terete; eglandular; glabrous.

Panicle open; lanceolate, or oblong; continuous; dense; straight; 15–20 cm long. Primary panicle branches 4–8 cm long. Panicle branches scabrous.

Spikelets solitary. Fertile spikelets pedicelled.

FERTILE SPIKELETS Spikelets comprising 4–6 fertile florets; with diminished florets at the apex. Spikelets lanceolate; laterally compressed; 7.5–10 mm long; breaking up at maturity; disarticulating below each fertile floret. Spikelet callus pilose. Rhachilla internodes scaberulous. Floret callus sparsely hairy.

GLUMES Glumes persistent; dissimilar; subequal in width; shorter than spikelet. Lower glume lanceolate; 3–4 mm long; 0.75–0.9 length of upper glume; herbaceous, or coriaceous; dark green; without keels; 1 -veined. Lower glume primary vein scabrous. Lower glume lateral veins absent. Lower glume apex acute. Upper glume lanceolate; 4–5.2 mm long; 0.75–0.9 length of adjacent fertile lemma; coriaceous; dark green; without keels; 3 -veined. Upper glume primary vein scabrous. Upper glume apex acute.

FLORETS Fertile lemma lanceolate; symmetrical; 5.5–6 mm long; chartaceous; dark green; without keel; 5 -veined. Lemma surface scabrous. Lemma apex acute; awned; 1 -awned. Principal lemma awn stiff; 1.5–2 mm long overall. Palea 2 -veined. Palea keels scabrous; adorned all along. Palea apex dentate; 2 -fid. Apical sterile florets resembling fertile though underdeveloped.

FLOWER Lodicules 2. Anthers 3; 2.5–3 mm long. Ovary with a few apical hairs.

FRUIT Caryopsis with adherent pericarp. Hilum linear.

DISTRIBUTION South America: western South America.

NOTES Poeae. Stancik 2005.

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