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 wiegandii

HABIT Perennial; caespitose. Rhizomes absent. Culms erect; 100–180(–200) cm long; 9–16 -noded. Culm-nodes glabrous. Leaves basal and cauline. Leaf-sheaths longer than adjacent culm internode; glabrous on surface, or hirsute. Leaf-sheath auricles falcate; 1–3 mm long. Ligule an eciliate membrane; 1 mm long. Leaf-blades (8–)10–20(–24) mm wide; dark green. Leaf-blade surface pilose; sparsely hairy; hairy adaxially.

INFLORESCENCE Inflorescence composed of racemes.

Racemes 1; single; drooping; bilateral; 10–30 cm long; 30–50 mm wide. Rhachis flattened; pubescent on surface (above). Spikelet packing broadside to rhachis. Rhachis internodes linear; 5–8(–12) mm long.

Spikelets in pairs. Fertile spikelets sessile.

FERTILE SPIKELETS Spikelets comprising (3–)4–6(–7) fertile florets; with diminished florets at the apex. Spikelets elliptic to oblong; laterally compressed; 12–20 mm long; breaking up at maturity; disarticulating below each fertile floret.

GLUMES Glumes persistent; similar; shorter than spikelet. Lower glume linear; 7–12 mm long; 1 length of upper glume; membranous; without keels; 1–3 -veined. Lower glume lateral veins absent, or distinct. Lower glume surface glabrous, or puberulous, or hispidulous. Lower glume apex awned; 1 -awned. Lower glume awn (5–)8–15(–18) mm long. Upper glume linear; 7–12 mm long; 0.75 length of adjacent fertile lemma; membranous; without keels; 1–3 -veined. Upper glume lateral veins absent, or distinct. Upper glume surface glabrous, or pubescent, or hispidulous. Upper glume awned; 1 -awned. Upper glume awn (5–)8–15(–18) mm long.

FLORETS Fertile lemma elliptic; 10–15 mm long; coriaceous; 5 -veined. Lemma surface glabrous, or pubescent. Lemma apex awned; 1 -awned. Principal lemma awn curved; spreading; 15–25(–30) mm long overall. Palea 9–14 mm long. Palea apex dentate; 2 -fid. Apical sterile florets resembling fertile though underdeveloped.

FLOWER Anthers 3; 2–3.5 mm long.

DISTRIBUTION North America: Subarctic, western Canada, eastern Canada, north-central USA, and northeast USA.

NOTES Triticeae. Fl N Amer 2007.

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