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.

Elymus tenuis

HABIT Perennial; caespitose; clumped loosely. Basal innovations extravaginal. Culms decumbent; weak; 50–100 cm long. Ligule an eciliate membrane; truncate. Collar glabrous. Leaf-blades flat, or conduplicate; 15–30 cm long; 1–2 mm wide; flaccid. Leaf-blade surface smooth; glabrous.

INFLORESCENCE Inflorescence composed of racemes.

Racemes 1; single; bilateral; 10–15 cm long; bearing 6–10 fertile spikelets on each. Rhachis flattened; scabrous on margins. Spikelet packing broadside to rhachis. Rhachis internodes linear. Rhachis internode tip flat.

Spikelets solitary. Fertile spikelets sessile.

FERTILE SPIKELETS Spikelets comprising 5–10 fertile florets; with diminished florets at the apex. Spikelets elliptic to oblong; laterally compressed; 8–10 mm long; breaking up at maturity; disarticulating below each fertile floret. Rhachilla internodes 2–3 mm long; sparsely hairy. Floret callus bearded.

GLUMES Glumes persistent; similar; shorter than spikelet. Lower glume lanceolate; 7–10 mm long; 1 length of upper glume; coriaceous; without keels; 3–5 -veined. Lower glume apex setaceously attenuate. Upper glume lanceolate; 7–10 mm long; coriaceous; without keels; 3–5 -veined. Upper glume apex setaceously attenuate.

FLORETS Fertile lemma lanceolate; 9–11 mm long; coriaceous; 3–5 -veined. Lemma surface scaberulous; rough above. Lemma apex dentate; 2 -fid; awned; 1 -awned. Principal lemma awn from a sinus; 30–40 mm long overall. Palea 1 length of lemma. Palea keels scabrous. Apical sterile florets resembling fertile though underdeveloped.

FLOWER Lodicules 2; membranous. Anthers 3; 2–3 mm long; yellow. Stigmas 2.

FRUIT Caryopsis with adherent pericarp.

DISTRIBUTION Australasia: New Zealand.

NOTES Triticeae. Connor 1994.

ADDITIONAL CHARACTERS Callus beard in a complete ring.

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