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.

Calamagrostis canadensis

HABIT Perennial. Rhizomes elongated. Culms 40–180 cm long. Culm-internodes smooth. Lateral branches lacking. Leaf-sheaths smooth, or antrorsely scabrous; glabrous on surface. Ligule an eciliate membrane; 2–10 mm long; lacerate. Collar glabrous, or pubescent. Leaf-blades flat, or involute; 3–8 mm wide. Leaf-blade surface scabrous.

INFLORESCENCE Inflorescence a panicle.

Panicle open; lanceolate, or ovate; dense, or loose; 15–25 cm long.

Spikelets solitary. Fertile spikelets pedicelled.

FERTILE SPIKELETS Spikelets comprising 1 fertile florets; with a barren rhachilla extension. Spikelets lanceolate; laterally compressed; 2.5–6 mm long; breaking up at maturity; disarticulating below each fertile floret. Floret callus bearded. Floret callus hairs 0.75–1 length of lemma.

GLUMES Glumes persistent; similar; exceeding apex of florets; firmer than fertile lemma. Lower glume elliptic; 2.5–6 mm long; 0.75–1 length of upper glume; chartaceous; 1-keeled; 1 -veined. Lower glume lateral veins absent. Lower glume surface scabrous. Lower glume apex acute. Upper glume elliptic; 2.5–6 mm long; 1–1.5 length of adjacent fertile lemma; chartaceous; 1-keeled; 1 -veined. Upper glume lateral veins absent. Upper glume surface scabrous. Upper glume apex acute.

FLORETS Fertile lemma oblong; 2.5–6 mm long; membranous; without keel; 5 -veined. Lemma apex dentate; 2 -fid; awned; 3 -awned. Principal lemma awn dorsal; arising 0.4–0.8 way up back of lemma; 2–6 mm long overall. Lateral lemma awns arising on apex of lobes; 0.2–1 mm long. Palea 0.75–0.8 length of lemma; hyaline; 2 -veined. Palea keels scaberulous. Rhachilla extension 0.2–1.3 mm long; pilose.

FLOWER Lodicules 2. Anthers 3; 1–1.7 mm long. Stigmas 2.

FRUIT Caryopsis with adherent pericarp. Hilum punctiform.

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

NOTES Aveneae. Fl Pac NW 1993.

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