1. Family: Poaceae Barnhart
    1. Hordeum L.

      1. This genus is accepted, and its native range is Temp. Eurasia, Macaronesia, N. & S. Africa, N. America to Guatemala, Bermuda, Peru to S. South America.

    [GB]

    nonem

    Habit
    Annual (10), or perennial (27). Rhizomes absent, or short (1). Culms erect (19/24), or geniculately ascending (14/24); slender (1/1); 3-49.84-150 cm long. Leaf-sheath auricles absent (25), or falcate (17). Ligule an eciliate membrane (34), or a ciliolate membrane (2). Leaf-blades filiform (1), or linear (35); stiff (2), or firm (34).
    Inflorescences
    Inflorescence composed of racemes; subtended by an unspecialized leaf-sheath (35), or an inflated leaf-sheath (1); exserted, or embraced at base by subtending leaf (7). Racemes single; erect (1), or ascending (35); linear (35), or oblong (3), or ovate (1); bilateral; bearing 20-44 fertile spikelets on each (1/2), or 45 fertile spikelets on each (2/2). Rhachis tough (4), or fragile at the nodes (33); wingless (33), or narrowly winged (3); flattened. Spikelet packing broadside to rhachis; 2 -rowed (2/4), or 6 -rowed (2/4). Rhachis internodes oblong (30), or cuneate (6); falling with spikelet above (33/33). Spikelets in threes. Fertile spikelets sessile, or sessile and pedicelled (1); 1 in the cluster (34), or 3 in the cluster (3). Companion sterile spikelets sessile (2/34), or pedicelled (33/34); 0 in the cluster (1/34), or 2 in the cluster (34/34). Pedicels oblong (32/32).
    Spikelets
    Companion sterile spikelets absent (3), or well-developed (34); persistent (3/34), or deciduous with the fertile (32/34). Companion sterile spikelet glumes awned (2/2). Spikelets comprising 1 fertile florets; without rhachilla extension (14), or with a barren rhachilla extension (24), or with diminished florets at the apex (2). Spikelets lanceolate (34), or ovate (1), or cuneate (1); dorsally compressed; 4-10.58-55 mm long; persistent on plant (3), or falling entire (33), or breaking up at maturity (1); deciduous with accessory branch structures (33/33); disarticulating below each fertile floret (1/1).
    Sterile
    Companion sterile spikelets absent (3), or well-developed (34); persistent (3/34), or deciduous with the fertile (32/34). Companion sterile spikelet glumes awned (2/2).
    Fertile
    Spikelets comprising 1 fertile florets; without rhachilla extension (14), or with a barren rhachilla extension (24), or with diminished florets at the apex (2). Spikelets lanceolate (34), or ovate (1), or cuneate (1); dorsally compressed; 4-10.58-55 mm long; persistent on plant (3), or falling entire (33), or breaking up at maturity (1); deciduous with accessory branch structures (33/33); disarticulating below each fertile floret (1/1).
    Glume
    Glumes collateral; shorter than spikelet (9/21), or reaching apex of florets (4/21), or exceeding apex of florets (11/21); parallel to lemmas (10), or recurved at apex (1), or gaping (25). Lower glume subulate (23), or linear (7), or lanceolate (7); 1 length of upper glume; coriaceous (12/12); 2-3 -veined (1/1). Lower glume lateral veins obscure (1), or distinct (35). Lower glume surface smooth (25), or scabrous (11); glabrous (31), or puberulous (1), or pubescent (2), or hispidulous (2). Lower glume apex acuminate (3/7), or setaceously attenuate (4/7); muticous (7/13), or awned (6/13). Upper glume subulate (23), or linear (7), or lanceolate (7); 0.3-0.7917-1.7 length of adjacent fertile lemma; coriaceous (12/12); 2-3 -veined (1/1). Upper glume surface smooth (27), or scabrous (9); glabrous (31), or puberulous (1), or pubescent (2), or hispidulous (2). Upper glume apex acuminate (3/7), or setaceously attenuate (4/7); muticous (7/13), or awned (6/13); 1 -awned (6/6).
    Florets
    Fertile lemma lanceolate (30), or elliptic (4), or ovate (3); coriaceous; without keel; 5 -veined (35), or 7-9 -veined (1). Lemma lateral veins obscure (3/4), or prominent (1/4). Lemma surface smooth (24), or asperulous (2), or scaberulous (5), or scabrous (7); glabrous (30), or puberulous (5), or pubescent (5), or pilose (1). Lemma apex entire (35), or dentate (1); 3 -fid (1/1); acuminate (34/35), or attenuate (1/35); without appendage (35), or with a trilobate appendage (1); muticous (4), or awned (35); 1 -awned (35/35). Principal lemma awn straight (34/35), or curved (1/35). Palea 1 length of lemma. Palea keels eciliate (35), or ciliate (1). Apical sterile florets rudimentary (2/2).
    Flowers
    Lodicules 2 (13/13); membranous (1/1); glabrous (4/13), or ciliate (10/13); obtuse (1/4), or acute (4/4). Anthers 3. Ovary pubescent on apex.
    Fruits
    Caryopsis with adherent pericarp; ellipsoid (4/6), or ovoid (2/6). Embryo 0.2 length of caryopsis. Hilum linear; 1 length of caryopsis.
    Distribution
    Europe (10), or Africa (9), or Temperate Asia (14), or Tropical Asia (8), or Australasia (6), or Pacific (3), or North America (10), or South America (25), or Antarctica (3).

    Images

    Distribution

    Native to:

    Afghanistan, Alabama, Alaska, Albania, Alberta, Aleutian Is., Algeria, Altay, Amur, Argentina Northeast, Argentina Northwest, Argentina South, Arizona, Arkansas, Austria, Azores, Baleares, Baltic States, Belarus, Belgium, Bermuda, Bolivia, Brazil South, British Columbia, Bulgaria, Buryatiya, California, Canary Is., Cape Provinces, Central European Rus, Chile Central, Chile North, Chile South, China North-Central, China South-Central, Chita, Colorado, Connecticut, Corse, Cyprus, Czechoslovakia, Delaware, Denmark, District of Columbia, East Aegean Is., East European Russia, Egypt, Florida, France, Free State, Georgia, Germany, Great Britain, Greece, Guatemala, Gulf States, Hungary, Idaho, Illinois, Indiana, Inner Mongolia, Iowa, Iran, Iraq, Ireland, Irkutsk, Italy, Juan Fernández Is., Kamchatka, Kansas, Kazakhstan, Kentucky, Khabarovsk, Kirgizstan, Korea, Krasnoyarsk, Kriti, Krym, Kuril Is., Kuwait, Labrador, Lebanon-Syria, Lesotho, Libya, Louisiana, Madeira, Magadan, Maine, Manchuria, Manitoba, Maryland, Masachusettes, Mauritania, Mexico Central, Mexico Northeast, Mexico Northwest, Michigan, Minnesota, Mississippi, Missouri, Mongolia, Montana, Morocco, Nebraska, Nepal, Netherlands, Nevada, New Brunswick, New Hampshire, New Jersey, New Mexico, New York, Newfoundland, North Carolina, North Caucasus, North Dakota, North European Russi, Northern Provinces, Northwest Territorie, Nova Scotia, Nunavut, Ohio, Oklahoma, Ontario, Oregon, Pakistan, Palestine, Pennsylvania, Peru, Poland, Portugal, Primorye, Prince Edward I., Qinghai, Québec, Rhode I., Romania, Sakhalin, Sardegna, Saskatchewan, Saudi Arabia, Selvagens, Sicilia, Sinai, South Carolina, South Dakota, South European Russi, Spain, Sweden, Switzerland, Tadzhikistan, Tennessee, Texas, Tibet, Transcaucasus, Tunisia, Turkey, Turkey-in-Europe, Turkmenistan, Tuva, Ukraine, Uruguay, Utah, Uzbekistan, Vermont, Virginia, Washington, West Himalaya, West Siberia, West Virginia, Wisconsin, Wyoming, Xinjiang, Yakutskiya, Yemen, Yugoslavia, Yukon

    Introduced into:

    Bangladesh, Chad, Chatham Is., China Southeast, Colombia, Cuba, Dominican Republic, East Himalaya, Easter Is., Ecuador, El Salvador, Ethiopia, Falkland Is., Fiji, Finland, Greenland, Gulf of Guinea Is., Haiti, Hawaii, Honduras, Iceland, India, Japan, Jawa, Kerguelen, Kermadec Is., KwaZulu-Natal, Mexican Pacific Is., Mexico Gulf, Mexico Southeast, Mexico Southwest, Myanmar, Nansei-shoto, New Caledonia, New South Wales, New Zealand North, New Zealand South, Niger, Nigeria, Norfolk Is., Northern Territory, Northwest European R, Norway, Oman, Queensland, Rwanda, South Australia, Sri Lanka, Taiwan, Tasmania, Victoria, Vietnam, Western Australia, Western Sahara, Windward Is.

    Hordeum L. appears in other Kew resources:

    First published in Sp. Pl.: 84 (1753)

    Accepted by

    • Govaerts, R.H.A. (2011). World checklist of selected plant families published update Facilitated by the Trustees of the Royal Botanic Gardens, Kew.

    Literature

    Flora of West Tropical Africa
    • Gen. Pl. ed. 5, 37 (1754).
    • Sp. Pl. 84 (1753)

    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 2019. 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 2019. 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