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 gigantea

HABIT Perennial; caespitose. Culms erect, or geniculately ascending; 45–150 cm long; 2–5 -noded. Culm-nodes purple. Leaf-sheaths without keel; smooth, or scaberulous; glabrous on surface. Leaf-sheath oral hairs lacking. Leaf-sheath auricles falcate. Ligule an eciliate membrane; 1–2.5 mm long. Leaf-blades drooping; flat; 30–60 cm long; 6–18 mm wide. Leaf-blade margins scaberulous. Leaf-blade apex attenuate.

INFLORESCENCE Inflorescence a panicle.

Panicle open; lanceolate, or ovate; effuse; nodding; 10–50 cm long. Primary panicle branches 2 -nate; bearing 3–8 fertile spikelets on each lower branch (on shorter branch). Panicle branches flexuous; angular; scabrous.

Spikelets solitary. Fertile spikelets pedicelled. Pedicels 1.5–6 mm long.

FERTILE SPIKELETS Spikelets comprising 3–10 fertile florets; with diminished florets at the apex. Spikelets lanceolate, or oblong; laterally compressed; 8–20 mm long; breaking up at maturity; disarticulating below each fertile floret. Rhachilla internodes definite.

GLUMES Glumes persistent; dissimilar; shorter than spikelet. Lower glume lanceolate; 4–7 mm long; 0.8–0.9 length of upper glume; chartaceous; much thinner on margins; without keels; 1–3 -veined. Lower glume apex acute. Upper glume lanceolate; 5–8 mm long; 0.8–0.9 length of adjacent fertile lemma; chartaceous; with membranous margins; without keels; 3 -veined. Upper glume apex acute.

FLORETS Fertile lemma elliptic; 6–9 mm long; chartaceous; of similar consistency on margins; without keel; 5 -veined. Lemma surface scaberulous. Lemma apex acute; awned; 1 -awned. Principal lemma awn straight, or flexuous; 10–18 mm long overall; limb scaberulous. Palea 1 length of lemma; 2 -veined. Palea keels scaberulous. Apical sterile florets resembling fertile though underdeveloped.

FLOWER Lodicules 2. Anthers 3; 2.5–3 mm long. Ovary glabrous.

FRUIT Caryopsis with adherent pericarp; fusiform; glabrous. Embryo 0.2 length of caryopsis. Hilum linear; 0.9 length of caryopsis.

DISTRIBUTION Europe: northern, central, southwestern, southeastern, and eastern. Asia-temperate: Siberia, Soviet Middle Asia, Caucasus, western Asia, and China. Asia-tropical: India.

NOTES Poeae. CEH.

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