Elymus canadensis

HABIT Perennial; caespitose. Rhizomes absent. Culms decumbent; 80–150 cm long. Leaf-sheath oral hairs lacking. Leaf-sheath auricles falcate. Ligule an eciliate membrane; 0.5–1 mm long; truncate. Leaf-blades flat, or conduplicate; 15–40 cm long; 4–12 mm wide. Leaf-blade surface glabrous, or pubescent.

INFLORESCENCE Inflorescence composed of racemes.

Racemes 1; single; deflexed, or drooping; bilateral; 8–20 cm long. Rhachis flattened; pubescent on surface (sparsely). Spikelet packing broadside to rhachis; irregular. Rhachis internodes oblong.

Spikelets in pairs, or clustered at each node. Fertile spikelets sessile; 2–4 in the cluster.

FERTILE SPIKELETS Spikelets comprising 3–5 fertile florets; with diminished florets at the apex. Spikelets elliptic to oblong; laterally compressed; 12–15 mm long; breaking up at maturity; disarticulating below each fertile floret. Spikelet callus glabrous; base truncate.

GLUMES Glumes persistent; similar; shorter than spikelet. Lower glume linear; 5–7 mm long; 1 length of upper glume; coriaceous; without keels; 2–4 -veined. Lower glume lateral veins ribbed. Lower glume surface scabrous. Lower glume apex acuminate; awned; 1 -awned. Lower glume awn 5–7 mm long. Upper glume linear; 5–7 mm long; 0.6–0.7 length of adjacent fertile lemma; coriaceous; without keels; 2–4 -veined. Upper glume lateral veins ribbed. Upper glume surface scabrous. Upper glume apex acuminate; awned; 1 -awned. Upper glume awn 5–7 mm long.

FLORETS Fertile lemma lanceolate; 8–10 mm long; coriaceous; without keel; 5 -veined. Lemma surface glabrous, or hispidulous. Lemma apex acute; awned; 1 -awned. Principal lemma awn flexuous; 15–50 mm long overall. Palea 2 -veined. Apical sterile florets resembling fertile though underdeveloped.

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

FRUIT Hilum linear.

DISTRIBUTION North America: Subarctic, western Canada, eastern Canada, northwest USA, north-central USA, northeast USA, southwest USA, south-central USA, southeast USA, and Mexico.

NOTES Triticeae. Gould.

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