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 humidorum

HABIT Perennial; caespitose; clumped loosely. Rhizomes short. Culms geniculately ascending; 40–90 cm long; 2–3 mm diam.; 4–7 -noded. Leaves basal and cauline. Leaf-sheaths outer margin glabrous. Ligule an eciliate membrane; 0.5–0.7 mm long; truncate. Leaf-blades 10–25 cm long; 3–8 mm wide; stiff. Leaf-blade surface scabrous; rough adaxially, or on both sides.

INFLORESCENCE Inflorescence composed of racemes.

Racemes 1; single; bilateral; 8–20 cm long; 7–10 mm wide. Rhachis flattened. Spikelet packing broadside to rhachis. Rhachis internodes linear; 7–15 mm long. Rhachis internode tip flat.

Spikelets solitary. Fertile spikelets sessile.

FERTILE SPIKELETS Spikelets comprising 4–10 fertile florets; with diminished florets at the apex. Spikelets elliptic to oblong; laterally compressed; 13–22 mm long; 5–6 mm wide; breaking up at maturity; disarticulating below each fertile floret. Rhachilla internodes 1–2 mm long; pubescent. Floret callus pubescent.

GLUMES Glumes persistent; similar; shorter than spikelet. Lower glume lanceolate; 5.5–7 mm long; 0.75–0.8 length of upper glume; coriaceous; without keels; 3–5 -veined. Lower glume apex acute. Upper glume lanceolate; 7–8.5 mm long; coriaceous; without keels; 5–7 -veined. Upper glume apex acute.

FLORETS Fertile lemma oblong; 8–11 mm long; coriaceous; much thinner on margins; 5 -veined. Lemma lateral veins ribbed. Lemma margins pubescent; hairy below. Lemma apex acute; awned; 1 -awned. Principal lemma awn 12–30 mm long overall. Palea oblong; 1 length of lemma. Palea keels winged; narrowly winged; ciliate. Apical sterile florets resembling fertile though underdeveloped.

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

FRUIT Caryopsis with adherent pericarp; oblong; 5–6 mm long; hairy at apex.

DISTRIBUTION Asia-temperate: eastern Asia.

NOTES Triticeae. Koyama 1994.

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