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 sororia

HABIT Perennial; caespitose. Rootstock evident. Culms 40–100 cm long. Lateral branches lacking. Leaf-sheaths glabrous on surface. Ligule an eciliate membrane; 0.5 mm long. Leaf-blades flat; 20–40 cm long; 3–7 mm wide. Leaf-blade surface smooth; glabrous. Leaf-blade margins scabrous.

INFLORESCENCE Inflorescence a panicle.

Panicle open; elliptic; loose; nodding; 10–15 cm long. Primary panicle branches drooping; 1–2 -nate.

Spikelets solitary. Fertile spikelets pedicelled.

FERTILE SPIKELETS Spikelets comprising 3–5 fertile florets; with diminished florets at the apex. Spikelets ovate; laterally compressed; 7–12 mm long; breaking up at maturity; disarticulating below each fertile floret.

GLUMES Glumes persistent; similar; shorter than spikelet. Lower glume lanceolate; 3 mm long; 0.6 length of upper glume; chartaceous; without keels; 1 -veined. Lower glume lateral veins absent. Lower glume apex acute. Upper glume lanceolate; 5 mm long; 0.5–0.6 length of adjacent fertile lemma; chartaceous; without keels; 3 -veined. Upper glume apex acute.

FLORETS Fertile lemma lanceolate; 6–9 mm long; chartaceous; without keel; 5 -veined. Lemma lateral veins distinct. Lemma surface smooth, or scaberulous; puberulous. Lemma apex acuminate; muticous, or awned; 1 -awned. Principal lemma awn 0–2 mm long overall. Palea 1 length of lemma; 2 -veined. Palea keels scabrous. Apical sterile florets resembling fertile though underdeveloped.

FLOWER Lodicules 2. Anthers 3. Ovary glabrous.

FRUIT Caryopsis with adherent pericarp. Hilum linear.

DISTRIBUTION North America: northwest USA, southwest USA, and south-central USA.

NOTES Poeae. Gr SW US 1994.

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