Elymus sibiricus

HABIT Perennial; caespitose. Rhizomes absent. Culms erect; 40–90 cm long; 1–2 mm diam.; 3–4 -noded. Leaves basal and cauline. Leaf-sheath oral hairs lacking. Leaf-sheath auricles falcate. Ligule an eciliate membrane; 0.5–1 mm long; truncate. Leaf-blades 6–20 cm long; 3–8 mm wide. Leaf-blade surface scaberulous; rough on both sides; glabrous, or pubescent; sparsely hairy; hairy adaxially. Leaf-blade apex acute.

INFLORESCENCE Inflorescence composed of racemes.

Racemes 1; single; arcuate; bilateral; 8–18 cm long. Rhachis flattened; pubescent on surface (sparsely); ciliate on margins. Spikelet packing broadside to rhachis. Rhachis internodes oblong; 5–8 mm long.

Spikelets in pairs. Fertile spikelets sessile; 2 in the cluster.

FERTILE SPIKELETS Spikelets comprising 4–5 fertile florets; with diminished florets at the apex. Spikelets elliptic to oblong; laterally compressed; 10–13 mm long; 2–3 mm wide; breaking up at maturity; disarticulating below each fertile floret. Spikelet callus glabrous; base truncate. Rhachilla internodes 1.5–2 mm long; pubescent.

GLUMES Glumes collateral; persistent; similar; shorter than spikelet. Lower glume lanceolate; 4–5 mm long; 1 length of upper glume; coriaceous; without keels; 3–7 -veined. Lower glume lateral veins ribbed. Lower glume surface scabrous. Lower glume apex acuminate; awned; 1 -awned. Lower glume awn 4–6 mm long. Upper glume lanceolate; 4–5 mm long; 0.4–0.5 length of adjacent fertile lemma; coriaceous; without keels; 3–5 -veined. Upper glume lateral veins ribbed. Upper glume surface scabrous. Upper glume apex acuminate; awned; 1 -awned. Upper glume awn 4–6 mm long.

FLORETS Fertile lemma lanceolate; 8–11 mm long; coriaceous; without keel; 5 -veined. Lemma surface scabrous; rough on veins; glabrous, or puberulous. Lemma apex acute; awned; 1 -awned. Principal lemma awn flexuous; 15–18 mm long overall. Palea 2 -veined. Palea keels ciliolate. Palea surface glabrous, or pubescent; hairy on back. Apical sterile florets resembling fertile though underdeveloped.

FLOWER Lodicules 2; membranous. Anthers 3; 1.5–2 mm long. Stigmas 2; protandrous; laterally exserted. Ovary pubescent on apex.

FRUIT Hilum linear.

DISTRIBUTION Europe: eastern. Asia-temperate: Siberia, Soviet far east, Soviet Middle Asia, western Asia, China, Mongolia, and eastern Asia. Asia-tropical: India. North America: Subarctic, western Canada, and eastern Canada.

NOTES Triticeae. Koyama.

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