1. Family: Poaceae Barnhart
    1. Genus: Elymus L.
      1. Elymus calderi Barkworth

        This species is accepted, and its native range is Alaska to W. Canada.

    [GB]
    Habit
    Perennial. Rhizomes elongated. Culms erect; 50-100 cm long. Culm-internodes thin-walled. Culm-nodes purple. Leaves mostly basal. Leaf-sheaths glabrous on surface, or puberulous; outer margin glabrous, or hairy. Leaf-sheath auricles falcate; 2-3 mm long. Ligule an eciliate membrane; 0.2-0.8 mm long; truncate. Collar pubescent. Leaf-blades 2-4 mm wide; stiff. Leaf-blade surface scaberulous; rough adaxially; glabrous, or pubescent; sparsely hairy; hairy abaxially.
    Inflorescences
    Inflorescence composed of racemes. Racemes 1; single; bilateral; 6-10 cm long. Rhachis flattened; glabrous on surface, or pubescent on surface; pubescent on margins. Spikelet packing broadside to rhachis. Rhachis internodes linear; 3-12.5 mm long. Rhachis internode tip flat. Spikelets solitary, or in pairs. Fertile spikelets sessile.
    Spikelets
    Spikelets comprising 4-10 fertile florets; with diminished florets at the apex. Spikelets elliptic to oblong; laterally compressed; 8.5-18 mm long; breaking up at maturity; disarticulating below each fertile floret. Rhachilla internodes pubescent.
    Fertile
    Spikelets comprising 4-10 fertile florets; with diminished florets at the apex. Spikelets elliptic to oblong; laterally compressed; 8.5-18 mm long; breaking up at maturity; disarticulating below each fertile floret. Rhachilla internodes pubescent.
    Glume
    Glumes collateral; persistent; similar; shorter than spikelet. Lower glume lanceolate; 3.5-12.5 mm long; 1 length of upper glume; coriaceous; without keels; 3(-5) -veined. Lower glume surface pubescent. Lower glume apex acute. Upper glume lanceolate; 3.5-12.5 mm long; 0.6-0.9 length of adjacent fertile lemma; coriaceous; without keels; 3(-5) -veined. Upper glume surface pubescent. Upper glume apex acute.
    Florets
    Fertile lemma lanceolate to oblong; 8-10 mm long; coriaceous; 5-7 -veined. Lemma surface villous. Lemma apex acute; muticous, or mucronate, or awned; 1 -awned. Principal lemma awn 1-2 mm long overall. Palea 1 length of lemma. Palea keels ciliolate; with hairs 0.2-0.6 mm long. Palea surface pubescent; hairy on back; hairy all along, or above. Palea apex emarginate, or truncate. Apical sterile florets resembling fertile though underdeveloped.
    Flowers
    Lodicules 2; membranous. Anthers 3. Stigmas 2.
    Fruits
    Caryopsis with adherent pericarp.
    Distribution
    North America: Subarctic.
    Reference
    Triticeae. Barkworth 2002.

    Distribution

    Native to:

    Alaska, British Columbia, Northwest Territorie, Yukon

    Elymus calderi Barkworth appears in other Kew resources:

    First published in Syst. Bot. 21: 353 (1987)

    Accepted by

    • Flora of North America Editorial Committee (2007). Flora of North America North of Mexico 24: 1-908. Oxford University Press, New York, Oxford.
    • Clayton, W.D., Harman, K.T. & Williamson, H. (2006). World Grass Species - Synonymy database The Board of Trustees of the Royal Botanic Gardens, Kew.

    Literature

    Kew Backbone Distributions
    • Flora of North America Editorial Committee (2007). Flora of North America North of Mexico 24: 1-908. Oxford University Press, New York, Oxford.

    Sources

    GrassBase - The Online World Grass Flora
    http://creativecommons.org/licenses/by-nc-sa/3.0

    Kew Backbone Distributions
    The International Plant Names Index and World Checklist of Selected Plant Families 2020. Published on the Internet at http://www.ipni.org and http://apps.kew.org/wcsp/
    © Copyright 2017 World Checklist of Selected Plant Families. http://creativecommons.org/licenses/by/3.0

    Kew Names and Taxonomic Backbone
    The International Plant Names Index and World Checklist of Selected Plant Families 2020. Published on the Internet at http://www.ipni.org and http://apps.kew.org/wcsp/
    © Copyright 2017 International Plant Names Index and World Checklist of Selected Plant Families. http://creativecommons.org/licenses/by/3.0