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.

Elymus tsukushiensis

HABIT Perennial; caespitose. Rhizomes absent. Culms erect, or geniculately ascending; 70–100 cm long; 2–3.3 mm diam.; 4–6 -noded. Culm-internodes distally glabrous. Leaf-sheaths glabrous on surface; outer margin hairy. Ligule an eciliate membrane; 0.5–0.7 mm long; truncate. Leaf-blades 15–40 cm long; (3–)10–15 mm wide; glaucous. Leaf-blade surface scabrous; rough adaxially; glabrous. Leaf-blade apex acute.

INFLORESCENCE Inflorescence composed of racemes.

Racemes 1; single; ascending; bilateral; 10–25 cm long; 8–12 mm wide. Rhachis flattened; scabrous on margins. Spikelet packing broadside to rhachis; distant. Rhachis internodes linear; 10–20 mm long. Rhachis internode tip flat.

Spikelets in pairs, or in threes. Fertile spikelets sessile.

FERTILE SPIKELETS Spikelets comprising 5–10 fertile florets; with diminished florets at the apex. Spikelets elliptic to oblong; laterally compressed; 15–25 mm long; 5 mm wide; breaking up at maturity; disarticulating below each fertile floret. Rhachilla internodes 2–2.5 mm long; pubescent. Floret callus glabrous, or sparsely hairy.

GLUMES Glumes persistent; similar; shorter than spikelet. Lower glume lanceolate, or elliptic; 4–6 mm long; 0.75 length of upper glume; coriaceous; without keels; 3 -veined. Lower glume surface scabrous; rough on veins; glabrous. Lower glume apex acute; muticous, or awned; 1 -awned. Lower glume awn 2.5 mm long. Upper glume lanceolate, or elliptic; 5–8 mm long; coriaceous; without keels; 5 -veined. Upper glume surface scabrous; rough on veins; glabrous. Upper glume apex acute; awned; 1 -awned. Upper glume awn 2.5 mm long.

FLORETS Fertile lemma lanceolate, or oblong; 8–12 mm long; coriaceous; much thinner on margins; 5 -veined. Lemma surface smooth, or asperulous; rough above, or on veins; hirsute, or villous. Lemma apex acute; awned; 1 -awned. Principal lemma awn straight, or curved; ascending; 20–40 mm long overall. Palea lanceolate; 1 length of lemma. Palea keels winged; narrowly winged; scaberulous; adorned above. Palea apex emarginate. Apical sterile florets resembling fertile though underdeveloped.

FRUIT Caryopsis with adherent pericarp.

DISTRIBUTION Asia-temperate: eastern Asia.

NOTES Triticeae. Baum et al 2013.

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