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 pallescens

HABIT Perennial; caespitose. Basal innovations intravaginal. Culms erect; 25–80 cm long. Lateral branches lacking. Leaf-sheaths open for most of their length; smooth, or scaberulous. Ligule a ciliolate membrane; 0.5 mm long; glabrous on abaxial surface, or pubescent on abaxial surface. Leaf-blades filiform; conduplicate; 5–35 cm long; 1–1.5 mm wide; herbaceous; glaucous. Leaf-blade surface glabrous. Leaf-blade apex acute.

INFLORESCENCE Inflorescence a panicle.

Panicle open; lanceolate; 5–15 cm long. Panicle axis scaberulous. Panicle branches scaberulous.

Spikelets solitary. Fertile spikelets pedicelled. Pedicels scaberulous.

FERTILE SPIKELETS Spikelets comprising 5–7 fertile florets; with diminished florets at the apex. Spikelets oblong; laterally compressed; 9–15 mm long; breaking up at maturity; disarticulating below each fertile floret. Rhachilla internodes 1.5–2.5 mm long.

GLUMES Glumes persistent; similar; shorter than spikelet. Lower glume lanceolate; 4.5–5 mm long; 0.75 length of upper glume; chartaceous; without keels; 1 -veined. Lower glume primary vein smooth, or scabrous. Lower glume lateral veins absent. Lower glume surface smooth, or asperulous; rough at apex. Lower glume apex acuminate. Upper glume lanceolate; 5.5–7.5 mm long; 0.66–0.75 length of adjacent fertile lemma; chartaceous; without keels; 3 -veined. Upper glume primary vein smooth, or scabrous. Upper glume surface smooth, or asperulous; rough at apex. Upper glume apex acuminate.

FLORETS Fertile lemma lanceolate; 6.5–11 mm long; chartaceous; without keel; 5 -veined. Lemma surface scaberulous; rough below. Lemma apex acute; awned; 1 -awned. Principal lemma awn 1–3 mm long overall. Palea 1 length of lemma; 2 -veined. Palea keels ciliolate. Palea surface scabrous. Apical sterile florets resembling fertile though underdeveloped.

FLOWER Lodicules 2. Anthers 3; 3.5–4.5 mm long. Ovary glabrous.

FRUIT Caryopsis with adherent pericarp. Hilum linear; 0.75 length of caryopsis.

DISTRIBUTION South America: southern South America.

NOTES Poeae. Fl Pat 1995.

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