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.

Glyceria borealis

HABIT Perennial. Rhizomes elongated. Culms geniculately ascending, or decumbent; 60–100 cm long; rooting from lower nodes. Leaf-sheaths smooth; glabrous on surface. Ligule an eciliate membrane; 5–10 mm long; acute. Leaf-blades flat, or conduplicate; 5–15 cm long; 3–5 mm wide. Leaf-blade surface scaberulous; glabrous. Leaf-blade margins scaberulous.

INFLORESCENCE Inflorescence a panicle.

Panicle open; linear; 20–45 cm long. Primary panicle branches appressed; 5–10 cm long; bearing 3–12 fertile spikelets on each lower branch.

Spikelets solitary. Fertile spikelets pedicelled.

FERTILE SPIKELETS Spikelets comprising 6–11 fertile florets; with diminished florets at the apex. Spikelets linear; subterete; 10–12 mm long; breaking up at maturity; disarticulating below each fertile floret.

GLUMES Glumes persistent; similar; shorter than spikelet. Lower glume oblong; 2–2.5 mm long; 0.66 length of upper glume; membranous; much thinner on margins; without keels; 1 -veined. Lower glume lateral veins absent. Lower glume apex obtuse. Upper glume oblong; 3 mm long; 0.9 length of adjacent fertile lemma; membranous; with hyaline margins; without keels; 1 -veined. Upper glume lateral veins absent. Upper glume apex obtuse.

FLORETS Fertile lemma oblong; 3.5 mm long; membranous; much thinner above; without keel; 7 -veined. Lemma lateral veins prominent. Lemma surface scaberulous; rough on veins. Lemma apex obtuse. Palea 1 length of lemma; 2 -veined. Apical sterile florets resembling fertile though underdeveloped.

FLOWER Lodicules 2; united; oblong; fleshy; truncate. Anthers 3.

FRUIT Caryopsis with adherent pericarp; 1.5 mm long. Hilum linear.

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

NOTES Meliceae. Fl Pac NW 1994.

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