GrassBase - The Online World Grass Flora

Descriptions

W.D. Clayton, M. Vorontsova, K.T. Harman & H. Williamson

© Copyright The Board of Trustees, Royal Botanic Gardens, Kew.

Elymus multisetus

HABIT Perennial; caespitose. Culms erect, or geniculately ascending; 25–60 cm long. Leaf-sheath oral hairs lacking. Leaf-sheath auricles falcate. Ligule an eciliate membrane. Leaf-blades 3–6 mm wide. Leaf-blade surface glabrous to hirsute; hairy on both sides.

INFLORESCENCE Inflorescence composed of racemes; exserted, or embraced at base by subtending leaf.

Racemes 1; single; oblong; bilateral; 5.5–12 cm long. Rhachis fragile at the nodes. Spikelet packing broadside to rhachis. Rhachis internodes linear; falling with spikelet above.

Spikelets ascending; in pairs. Fertile spikelets sessile; 2(–4) in the cluster; heteromorphic (one in each pair with sterile lower floret).

FERTILE SPIKELETS Spikelets comprising 0–1 basal sterile florets; 1–3 fertile florets; with diminished florets at the apex. Spikelets lanceolate; dorsally compressed; 8–10 mm long; falling entire; deciduous with accessory branch structures; readily shedding fertile florets. Floret callus evident.

GLUMES Glumes collateral; similar; exceeding apex of florets; gaping. Lower glume linear, or elliptic; 2–6 mm long; 1 length of upper glume; coriaceous; 3–9 -veined. Lower glume apex dentate; 3–9 -fid; awned; 3–9 -awned (unequally). Lower glume awn 25–100 mm long. Upper glume linear, or elliptic; 2–6 mm long; coriaceous; 3–9 -veined. Upper glume apex dentate; 3–9 -fid; awned; 3–9 -awned (unequally). Upper glume awn 25–100 mm long.

FLORETS Basal sterile florets barren; without significant palea. Lemma of lower sterile floret similar to upper glume; linear, or oblong; 2–6 mm long; coriaceous; dentate; 2–3 -fid; awned (2–3 awned). Awn of lower sterile floret 25–100 mm long. Fertile lemma lanceolate; 8–10 mm long; coriaceous; without keel; 5 -veined. Lemma surface smooth, or scabrous; rough above. Lemma apex dentate; 2 -fid; awned; 3 -awned. Principal lemma awn from a sinus; 30–100 mm long overall. Lateral lemma awns arising on apex of lobes; 1–20 mm long; shorter than principal. Palea coriaceous. Palea keels scabrous. Palea apex with excurrent keel veins. Apical sterile florets resembling fertile though underdeveloped.

FLOWER Ovary with a fleshy appendage below style insertion; pubescent on apex.

DISTRIBUTION North America: northwest USA, southwest USA, and Mexico.

NOTES Triticeae. WDC.

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