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 trachycaulus

HABIT Perennial; caespitose. Culms erect, or geniculately ascending; 40–110 cm long. Leaf-sheaths glabrous on surface, or puberulous. Ligule an eciliate membrane; 1 mm long. Leaf-blades 2–6 mm wide. Leaf-blade surface smooth, or scaberulous.

INFLORESCENCE Inflorescence composed of racemes.

Racemes 1; single; bilateral; 6–15 cm long. Rhachis flattened. Spikelet packing broadside to rhachis; 0.5 their length apart. Rhachis internodes linear; 6–20 mm long.

Spikelets solitary. Fertile spikelets sessile.

FERTILE SPIKELETS Spikelets comprising 4–7 fertile florets; with diminished florets at the apex. Spikelets elliptic to oblong; laterally compressed; 12–24 mm long; breaking up at maturity; disarticulating above glumes but not between florets. Rhachilla internodes 3 mm long.

GLUMES Glumes collateral; persistent; similar; shorter than spikelet. Lower glume lanceolate; 9–15 mm long; 1 length of upper glume; membranous; without keels; 3–7 -veined. Lower glume apex acute; muticous, or mucronate. Upper glume lanceolate; 9–15 mm long; 1 length of adjacent fertile lemma; membranous; without keels; 3–7 -veined. Upper glume apex acute; muticous, or mucronate.

FLORETS Fertile lemma lanceolate to oblong; 8–13 mm long; coriaceous; 5–7 -veined. Lemma lateral veins obscure. Lemma apex acute; muticous, or awned; 1 -awned. Principal lemma awn 1–3 mm long overall. Palea 1 length of lemma. Palea keels scabrous. Apical sterile florets resembling fertile though underdeveloped.

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

FRUIT Caryopsis with adherent pericarp.

DISTRIBUTION Europe: eastern. Asia-temperate: Siberia, Soviet far east, Soviet Middle Asia, and Mongolia. North America: Subarctic, western Canada, eastern Canada, northwest USA, north-central USA, northeast USA, southwest USA, south-central USA, and Mexico.

NOTES Triticeae. Gr Tex 1993.

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