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 alaskanus

HABIT Perennial; caespitose. Rhizomes absent, or short. Culms erect, or geniculately ascending; 20–90 cm long. Culm-nodes glabrous, or pubescent. Leaf-sheaths smooth, or scaberulous; glabrous on surface, or puberulous. Leaf-sheath auricles absent, or falcate; 0.5 mm long. Ligule a ciliolate membrane; 0.2–1 mm long. Leaf-blades 7–15 cm long; 3–7 mm wide. Leaf-blade surface smooth, or scabrous; glabrous, or pubescent.

INFLORESCENCE Inflorescence composed of racemes.

Racemes 1; single; straight, or arcuate; bilateral; 3.5–14 cm long; 5–8 mm wide. Rhachis flattened; 0.5–0.8 mm wide; glabrous on surface; scabrous on margins. Spikelet packing broadside to rhachis. Rhachis internodes linear; 3–10 mm long; 0.4 length of fertile spikelet. Rhachis internode tip flat.

Spikelets appressed; solitary. Fertile spikelets sessile.

FERTILE SPIKELETS Spikelets comprising 3–6 fertile florets; with diminished florets at the apex. Spikelets elliptic to oblong; laterally compressed; 9–15(–20) mm long; breaking up at maturity; disarticulating below each fertile floret. Rhachilla internodes pubescent.

GLUMES Glumes persistent; similar; shorter than spikelet. Lower glume lanceolate; 4–8 mm long; 1 length of upper glume; coriaceous; without keels. Lower glume surface glabrous, or pubescent. Lower glume apex setaceously attenuate. Upper glume lanceolate; 4–8 mm long; 0.33–0.66 length of adjacent fertile lemma; coriaceous; without keels. Upper glume surface glabrous, or pubescent. Upper glume apex setaceously attenuate.

FLORETS Fertile lemma elliptic; 7–11 mm long; coriaceous; 5 -veined. Lemma surface glabrous, or pubescent. Lemma apex acute; muticous, or awned; 1 -awned. Principal lemma awn 0–7 mm long overall. Palea 1 length of lemma. Apical sterile florets resembling fertile though underdeveloped.

FLOWER Anthers 3; 1–2 mm long.

DISTRIBUTION North America: Subarctic, western Canada, and eastern Canada.

NOTES Triticeae. Fl N Amer 2007.

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