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 valdesii

HABIT Perennial; caespitose; clumped densely. Butt sheaths persistent and investing base of culm; with fibrous dead sheaths. Basal innovations extravaginal and intravaginal. Culms geniculately ascending; 80–130 cm long; 1.5–3 mm diam. Leaf-sheaths smooth, or scaberulous. Leaf-sheath auricles absent. Ligule a ciliolate membrane; 0.5–1 mm long; truncate. Leaf-blades flat, or involute, or convolute; 25–35 cm long; 2.4–4 mm wide. Leaf-blade surface ribbed; scaberulous; rough on both sides. Leaf-blade apex attenuate.

INFLORESCENCE Inflorescence a panicle.

Panicle open; ovate; 17–25 cm long. Primary panicle branches 1–2 -nate; bearing 6–12 fertile spikelets on each lower branch.

Spikelets solitary. Fertile spikelets pedicelled.

FERTILE SPIKELETS Spikelets comprising 2–5 fertile florets; with diminished florets at the apex. Spikelets oblong; laterally compressed; 8–14.3 mm long; breaking up at maturity; disarticulating below each fertile floret.

GLUMES Glumes persistent; similar; shorter than spikelet. Lower glume lanceolate; 4–8.3 mm long; 0.8–0.9 length of upper glume; chartaceous; without keels; 1 -veined. Lower glume primary vein scabrous. Lower glume lateral veins absent. Lower glume surface scabrous; rough at apex. Lower glume apex acute. Upper glume lanceolate; 4.6–10.1 mm long; 0.8–1.1 length of adjacent fertile lemma; chartaceous; without keels; 3 -veined. Upper glume primary vein scabrous. Upper glume surface scabrous; rough at apex. Upper glume apex acute.

FLORETS Fertile lemma lanceolate; 6.2–9.9 mm long; chartaceous; without keel; 3–5 -veined. Lemma lateral veins prominent. Lemma surface scaberulous, or scabrous. Lemma apex acute; muticous. Palea 2 -veined. Apical sterile florets resembling fertile though underdeveloped.

FLOWER Lodicules 2; entire. Anthers 3; 2.8–3.5 mm long. Ovary pubescent on apex.

FRUIT Caryopsis with adherent pericarp; 4 mm long. Hilum linear.

DISTRIBUTION North America: Mexico.

NOTES Poeae. Gonz.-Ledesma 2004.

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