GrassBase - The Online World Grass Flora


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

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

Festuca oroana

HABIT Caespitose; clumped densely. Cataphylls inconspicuous. Basal innovations intravaginal. Culms of moderate stature; straight; without nodal roots. Culm-internodes terete. Culm-nodes without exudate; glabrous. Lateral branches lacking. Leaves mostly basal; 0–2 per branch. Leaf-sheaths tight; unthickened at base; open for most of their length; without keel; striately veined. Ligule an eciliate membrane; membranous; white; entire; truncate. Leaf-blade base symmetrical. Leaf-blades straight; angular in section; stiff, or firm; dark green. Leaf-blade midrib indistinct, or evident. Leaf-blade venation indistinct, or distinct; with subepidermal sclerenchyma strands similar in size; with subepidermal sclerenchyma attached to veins below; without layer of subepidermal sclerenchyma masking vein striation. Leaf-blade surface glabrous. Leaf-blade margins smooth; glabrous. Leaf-blade apex attenuate.

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

Panicle open, or contracted; oblong, or ovate; continuous; loose; straight; 20 cm long; 25 cm wide. Primary panicle branches ascending, or spreading; moderately divided; naked below, or bearing spikelets almost to the base. Panicle branches straight, or arcuate.

FERTILE SPIKELETS Spikelets comprising 4–6 fertile florets; with diminished florets at the apex. Spikelets elliptic; laterally compressed; 9–10 mm long; breaking up at maturity; disarticulating below each fertile floret. Spikelet callus pilose. Rhachilla internodes scaberulous. Floret callus pilose.

GLUMES Glumes persistent; similar; subequal in width; shorter than spikelet. Lower glume lanceolate; 2.4–2.6 mm long; 0.5–0.7 length of upper glume; chartaceous, or herbaceous; dark green; without keels; 1 -veined. Lower glume apex acute. Upper glume lanceolate; 3.6–3.9 mm long; 0.66 length of adjacent fertile lemma; chartaceous, or scarious; dark green; without keels; 3 -veined. Upper glume apex obtuse, or acute.

FLORETS Fertile lemma lanceolate; symmetrical; 5.5–6(–6.5) mm long; chartaceous, or herbaceous; mid-green. Lemma apex awned; 1 -awned. Principal lemma awn stiff; 0.5–1 mm long overall.

DISTRIBUTION South America: western South America.

NOTES Poeae. Stancik 2005.

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