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.

Bromus porteri

HABIT Perennial. Culms 30–100 cm long. Culm-internodes distally glabrous. Culm-nodes glabrous, or pubescent. Leaf-sheaths glabrous on surface, or pilose. Ligule an eciliate membrane; 2.5 mm long; truncate, or obtuse. Leaf-blades 4–8 mm wide. Leaf-blade surface glabrous, or pilose; hairy adaxially.

INFLORESCENCE Inflorescence a panicle.

Panicle open; ovate; nodding; 7–15 cm long. Primary panicle branches drooping.

Spikelets solitary. Fertile spikelets pedicelled.

FERTILE SPIKELETS Spikelets comprising 6–10 fertile florets; with diminished florets at the apex. Spikelets oblong; laterally compressed; 12–15 mm long; breaking up at maturity; disarticulating below each fertile floret.

GLUMES Glumes persistent; shorter than spikelet. Lower glume lanceolate; membranous; without keels; 3 -veined. Lower glume surface pubescent. Upper glume lanceolate; membranous; without keels; 3 -veined. Upper glume surface pubescent.

FLORETS Fertile lemma oblong; 8–14 mm long; chartaceous; without keel; 5 -veined. Lemma surface pubescent, or pilose. Lemma apex awned; 1 -awned. Principal lemma awn subapical; 1–3.5 mm long overall. Apical sterile florets resembling fertile though underdeveloped.

FLOWER Anthers 3; 2–3 mm long. Ovary with a fleshy appendage above style insertion; pubescent on apex.

FRUIT Caryopsis with adherent pericarp; hairy at apex.

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

NOTES Bromeae. Pavlick 2004.

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