| # The Families of Angiosperms |

L. Watson and M.J. Dallwitz

### Gramineae Juss.

Alternatively Poaceae Barnhart (nom. altern.).

Including Agrostidaceae Burnett, Andropogonaceae (J. Presl) Herter, Anomochloaceae Nak., Arundinaceae (Dum.) Herter, Arundinellaceae (Stapf) Herter, Avenaceae (Kunth) Herter, Bambusaceae Nak., Chloridaceae (Reichenb.) Herter, Eragrostidaceae (Benth.) Herter, Hordeaceae Burnett, Lepturaceae (Benth.) Herter, Miliaceae Burnett, Oryzaceae (Kunth) Herter, Panicaceae (R. Br.) Herter, Pappophoraceae (Kunth) Herter, Parianaceae (Hack.) Nak., Phalaridaceae Burnett, Spartinaceae Burnett, Sporobolaceae (Stapf) Herter, Stipaceae Burnett, Streptochaetaceae (C.E. Hubb.) Nak.

Habit and leaf form. Herbs, or shrubs, or ‘arborescent’, or lianas. ‘Normal’ plants (usually), or switch-plants (occasionally, e.g. Spartochloa, Xerochloa). Leaves well developed, or much reduced (rarely). Annual, or biennial, or perennial; with a basal aggregation of leaves, or without conspicuous aggregations of leaves. Young stems breaking easily at the nodes, or not breaking easily at the nodes (in bamboos). (0.003–)0.01–30(–40) m high; when perennial, rhizomatous (or stoloniferous), or tuberous (rarely). Self supporting, or climbing (or decumbent); the climbers stem twiners, or root climbers, or scrambling. Hydrophytic to xerophytic; when hydrophytic, rooted. Leaves of hydrophytes submerged and emergent, or submerged, emergent, and floating. Not conspicuously heterophyllous (usually), or conspicuously heterophyllous (occasionally). Leaves persistent, or deciduous; minute to large; alternate; nearly always initially distichous (very rarely spiral - Micraira and the Orcuttieae); flat, or folded, or rolled, or terete (rarely); ‘herbaceous’ (usually), or leathery, or membranous (rarely); sessile, or petiolate; sheathing. Leaf sheaths tubular; with free margins, or with joined margins. Leaves not gland-dotted; without marked odour (usually), or aromatic (occasionally); simple. Lamina entire; setaceous, or acicular, or linear to obovate; parallel-veined (usually), or pinnately veined to palmately veined (rarely); without cross-venules, or cross-venulate. Leaves nearly always ligulate (though the ligule is often reduced to a fringe of hairs or even to papillae, sometimes lacking on upper leaves, as in Echinochloa, and totally absent from the lilylike leaves of Neostapfia and the Orcuttieae). Lamina margins nearly always entire; flat, or revolute, or involute. Prophylls 1. Leaf development ‘graminaceous’. Vernation conduplicate, or involute, or revolute, or convolute, or plicate (rarely).

General anatomy. Plants with silica bodies. Chlorenchyma without ‘peg cells’.

Leaf anatomy. The leaf lamina usually dorsiventral; exhibiting epidermal salt glands (rarely, these represented by highly specialised ‘chloridoid type’ microhairs with complex partitioning membranes, in some Chloridoideae only), or without epidermal salt glands (most microhairs - including ‘chloridoid type’ - secreting only polysaccharides and/or proteins). Epidermis nearly always conspicuously differentiated into ‘long’ and ‘short’ cells; nearly always containing silica bodies. Abaxial epidermis papillose, or not papillose. Mucilaginous epidermis absent. Stomata mainly confined to one surface, or on both surfaces; paracytic. Guard-cells ‘grass type’ (inevitably with an exception — Neostapfia). Hairs of some type nearly always present; eglandular (with simple macrohairs and prickles represented in all groups, including Pooideae), or eglandular and glandular (secretory microhairs lacking only in Pooideae); unicellular (macrohairs and prickles), or unicellular and multicellular (microhairs universally two-celled, and some macrohairs septate-uniseriate). Unicellular hairs simple. Multicellular hairs uniseriate; simple. Complex hairs absent. Adaxial hypodermis usually absent. Lamina usually without secretory cavities. Cystoliths absent. The mesophyll not containing mucilage cells; usually without crystals (and never with raphides). Midrib conspicuous, or not conspicuous; with a single bundle, a simple arc, or a ‘complex’. Main veins vertically transcurrent, or embedded. Foliar vessels present; with simple end-wall perforations, or with scalariform end-walls and with simple end-wall perforations. Minor leaf veins without phloem transfer cells (in an unspecified ‘large sample, including Arundinaria’).

Axial (stem, wood) anatomy. Young stems cylindrical (usually), or oval in section; with solid internodes, or with spongy internodes, or with hollow internodes (commonly). Secretory cavities absent. Cork cambium absent. Primary vascular tissues comprising two or more rings of bundles, or consisting of scattered bundles. Secondary thickening absent.

The vessel end-walls simple (usually), or scalariform and simple.

Root anatomy. Root xylem with vessels; vessel end-walls simple, or scalariform and simple (then mainly simple).

Reproductive type, pollination. Unisexual flowers present, or absent. Plants hermaphrodite, or monoecious, or andromonoecious, or gynomonoecious, or dioecious, or androdioecious, or gynodioecious, or polygamomonoecious; viviparous (occasionally), or not viviparous. Floral nectaries absent (nectaries absent). Pollination almost exclusively anemophilous (with possible exceptions in South American forest-floor Olyreae).

Inflorescence, floral, fruit and seed morphology. Flowers aggregated in ‘inflorescences’ (these consisting of at least one ‘spikelet’); in ‘spikelets’. The ultimate inflorescence units (the spikelet) cymose (e.g. Panicoideae), or racemose (e.g. Pooideae). Inflorescences terminal, or axillary; with 1–50 florets and vestiges grouped into characteristic ‘spikelets’ in association with specialised bracts termed ‘glumes’, ‘lemmas’ and ‘paleas’, the spikelets variously gathered into simple or compound panicles, racemes, spikes, heads or fascicles; with involucral bracts, or without involucral bracts; spatheate, or espatheate. Flowers bracteate (in that the spikelets normally exhibit glumes and lemmas, and the other inflorescence branches are sometimes spatheate or spatheolate); bracteolate (if the palea, when present, is interpreted as a bracteole), or ebracteolate; minute to small. Perigone tube absent. Hypogynous disk absent.

Perianth vestigial (if the lodicules are interpreted as perianth), or absent (the lodicules being sometimes absent); 0, or (1–)2–3(–6); (lodicules) free to joined; 1 whorled.

Androecium (1–)2–3, or 4 (rarely), or 6, or 6–120 (Ochlandra). Androecial members free of the perianth, or adnate; usually free of one another, or coherent (occasionally, the filaments are joined to one another or to the lodicules). Androecium exclusively of fertile stamens. Stamens (1–)2–3, or 4, or 6–120; filantherous. Anthers basifixed (sagittate); non-versatile; dehiscing via pores, or dehiscing via short slits, or dehiscing via longitudinal slits; extrorse, or introrse, or latrorse; tetrasporangiate. Endothecium developing fibrous thickenings. The endothecial thickenings girdling. Microsporogenesis successive. The initial microspore tetrads isobilateral, or T-shaped, or linear. Anther wall initially with one middle layer; of the ‘monocot’ type. Tapetum glandular. Pollen shed as single grains. Pollen grains aperturate; 1 aperturate; ulcerate. The ulcus operculate; with an annulus. Interapertural exine not scrobiculate. Interapertural interstitium columellate. Pollen grains 3-celled (recorded in 23 genera).

Gynoecium theoretically 2(–3) carpelled. The pistil 1 celled. Gynoecium syncarpous; synovarious to eu-syncarpous; superior. Ovary 1 locular. Styles 1, or 2(–3); free to partially joined; attenuate from the ovary, or from a depression at the top of the ovary; apical, or lateral. Stigmas (1–)2–3; dry type; papillate, or non-papillate; Group I type (usually), or Group II type (rarely, IIB). Placentation basal to parietal (stachysporous, the ovule fused to the adaxial wall). Ovules in the single cavity 1; sessile (usually adnate); non-arillate; (hemi-) campylotropous, or hemianatropous (see Anton de Triquell, 1887); usually bitegmic; tenuinucellate (especially Pooideae), or pseudocrassinucellate (mostly). Outer integument contributing to the micropyle (rarely?), or not contributing to the micropyle (and rarely the integuments are variously reduced or absent). Embryo-sac development Polygonum-type (the ‘Poaceae variant’, i.e. with dividing antipodals). Antipodal cells formed; characteristically proliferating (to 300 or more cells in ‘Sasa paniculata’); ephemeral. Synergids sometimes hooked; haustorial (in danthonioids), or non-haustorial (generally). Endosperm formation nuclear. Embryogeny asterad.

Fruit non-fleshy (usually), or fleshy (occasionally); indehiscent; a caryopsis (usually), or capsular-indehiscent (occasionally, a utricle), or achene-like (not infrequently), or a nut, or a berry. Dispersal unit the fruit, or the inflorescence. Seeds nearly always endospermic. Endosperm not ruminate (very rarely ruminate); not oily. Seeds with starch. Embryo well differentiated. Cotyledons (usually identified with the scutellum) 1. Embryo achlorophyllous (9/13); straight, or bent.

Seedling. Hypocotyl internode absent. Mesocotyl present (e.g. Panicoideae, Chloridoideae), or absent (e.g. Pooideae). Seedling collar conspicuous (in the form of the epiblast), or not conspicuous. Cotyledon hyperphyll compact (reduced to the haustorium within the caryopsis); non-assimilatory. Coleoptile present. Seedling cataphylls present (in some bambusoid genera), or absent (mostly). First leaf dorsiventral. Primary root ephemeral (virtually absent).

Physiology, phytochemistry. C3, or C4, or C3-C4 intermediate. C3 physiology recorded directly in 366 genera: see Watson and Dallwitz database. C4 physiology recorded directly in 335 genera: see Watson and Dallwitz database. C3-C4 intermediacy in Neurachne minor, Steinchisma (Panicum) decipiens, S. hians (= milioides), S. spathellosum (= schenckii). Anatomy C4 type (in 328 genera), or non-C4 type (in 366 genera). Accumulated starch other than exclusively ‘pteridophyte type’. Cyanogenic, or not cyanogenic. Cynogenic constituents tyrosine-derived. Alkaloids present (sometimes, isoquinoline, pyrrolizidine and indole), or absent. Arbutin absent. Saponins/sapogenins present (rarely), or absent. Proanthocyanidins present (rarely, only in Panicoideae and Chloridoideae, and there in only trace amounts), or absent; when present, cyanidin. Flavonols present (only in Glyceria and Melica), or absent (60 genera); when present, quercetin, or kaempferol and quercetin. Ellagic acid absent. Plants accumulating free oxalates (e.g. Setaria anceps), or not accumulating free oxalates. Sieve-tube plastids P-type; type II (b).

Geography, cytology. Holarctic, Paleotropical, Neotropical, Cape, Australian, and Antarctic. Frigid zone, temperate, sub-tropical, and tropical. Cosmopolitan.

Taxonomy. Subclass Monocotyledonae. Dahlgren et al. Superorder Commeliniflorae (dubiously); Poales. APG III core angiosperms; Superorder Lilianae; commelinid Monocot. APG IV Order Poales.

Species about 12000. Genera about 700; Acamptoclados, Achlaena, Achnatherum, Aciachne, Acidosasa, Acostia, Acrachne, Acritochaete, Acroceras, Actinocladum, Aegilops, Aegopogon, Aeluropus, Afrotrichloris, Agenium, Agnesia, Agropyron, Agropyropsis, Agrostis, Aira, Airopsis, Alexfloydia, Alloeochaete, Allolepis, Alloteropsis, Alopecurus, Alvimia, Amblyopyrum, Ammochloa, Ammophila, Ampelodesmos, Amphibromus, Amphicarpum, Amphipogon, Anadelphia, Anadelphia, Ancistrachne, Ancistragrostis, Andropogon, Andropterum, Anemanthele, Aniselytron, Anisopogon, Anomochloa, Anthaenantiopsis, Anthenantia, Anthephora, Anthochloa, Anthoxanthum, Antinoria, Apera, Aphanelytrum, Apluda, Apochiton, Apoclada, Apocopis, Arberella, Arctagrostis, Arctophila, Aristida, Arrhenatherum, Arthragrostis, Arthraxon, Arthropogon, Arthrostylidium, Arundinaria, Arundinella, Arundo, Arundoclaytonia, Asthenochloa, Astrebla, Athroostachys, Atractantha, Aulonemia, Australopyrum, Austrochloris, Austrodanthonia, Austrofestuca, Austrostipa, Avellinia, Avena, Axonopus, Bambusa, Baptorhachis, Bealia, Beckeropsis, Beckmannia, Bellardiochloa, Bewsia, Bhidea, Blepharidachne, Blepharoneuron, Boissiera, Boivinella, Borinda, Bothriochloa, Bouteloua, Brachiaria, Brachyachne, Brachychloa, Brachyelytrum, Brachypodium, Briza, Bromuniola, Bromus, Brylkinia, Buchloë, Buchlomimus, Buergersiochloa, Calamagrostis, Calamovilfa, Calderonella, Calosteca, Calyptochloa, Camusiella, Capillipedium, Castellia, Catabrosa, Catabrosella, Catalepis, Catapodium, Cathestechum, Cenchrus, Centotheca, Centrochloa, Centropodia, Cephalostachyum, Chaboissaea, Chaetium, Chaetobromus, Chaetopoa, Chaetopogon, Chaetostichium, Chamaeraphis, Chandrasekharania, Chasechloa, Chasmanthium, Chasmopodium, Chevalierella, Chikusichloa, Chimonobambusa, Chionachne, Chionochloa, Chloachne, Chloris, Chlorocalymma, Chrysochloa, Chrysopogon, Chumsriella, Chusquea, Cinna, Cladoraphis, Clausospicula, Cleistachne, Cleistochloa, Cliffordiochloa, Cockaynea, Coelachne, Coelachyropsis, Coelachyrum, Coelorachis, Coix, Colanthelia, Coleanthus, Colpodium, Commelinidium, Cornucopiae, Cortaderia, Corynephorus, Cottea, Craspedorhachis, Crinipes, Crithopsis, Crypsis, Cryptochloa, Ctenium, Ctenopsis, Cutandia, Cyathopus, Cyclostachya, Cymbopogon, Cymbosetaria, Cynodon, Cynosurus, Cyperochloa, Cyphochlaena, Cypholepis, Cyrtococcum, Dactylis, Dactyloctenium, Daknopholis, Dallwatsonia, Danthonia, Danthoniastrum, Danthonidium, Danthoniopsis, Dasyochloa, Dasypoa, Dasypyrum, Davidsea, Decaryella, Decaryochloa, Dendrocalamus, Dendrochloa, Deschampsia, Desmazeria, Desmostachya, Deyeuxia, Diandrochloa, Diandrolyra, Diandrostachya, Diarrhena, Dichaetaria, Dichanthelium, Dichanthium, Dichelachne, Diectomis, Dielsiochloa, Digastrium, Digitaria, Digitariopsis, Dignathia, Diheteropogon, Dilophotriche, Dimeria, Dimorphochloa, Dinebra, Dinochloa, Diplachne, Diplopogon, Dissanthelium, Dissochondrus, Distichlis, Drake-Brockmania, Dregeochloa, Dryopoa, Dupontia, Duthiea, Dybowskia, Eccoilopus, Eccoptocarpha, Echinaria, Echinochloa, Echinolaena, Echinopogon, Ectrosia, Ectrosiopsis, Ehrharta, Ekmanochloa, Eleusine, Elionurus, Elymandra, Elymus, Elytrigia, Elytrophorus, Elytrostachys, Enneapogon, Enteropogon, Entolasia, Entoplocamia, Eragrostiella, Eragrostis, Eremium, Eremochloa, Eremopoa, Eremopogon, Eremopyrum, Eriachne, Erianthecium, Erianthus, Eriochloa, Eriochrysis, Erioneuron, Euchlaena, Euclasta, Eulalia, Eulaliopsis, Eustachys, Euthryptochloa, Exotheca, Fargesia, Farrago, Fasciculochloa, Festuca, Festucella, Festucopsis, Fingerhuthia, Froesiochloa, Garnotia, Gastridium, Gaudinia, Gaudiniopsis, Germainia, Gerritea, Gigantochloa, Gilgiochloa, Glaziophyton, Glyceria, Glyphochloa, Gouinia, Gouldochloa, Graphephorum, Greslania, Griffithsochloa, Guaduella, Gymnachne, Gymnopogon, Gynerium, Habrochloa, Hackelochloa, Hainardia, Hakonechloa, Halopyrum, Harpachne, Harpochloa, Helictotrichon, Helleria, Hemarthria, Hemisorghum, Henrardia, Hesperostipa, Heterachne, Heteranthelium, Heteranthoecia, Heterocarpha, Heteropholis, Heteropogon, Hickelia, Hierochloë, Hilaria, Hitchcockella, Holcolemma, Holcus, Homolepis, Homopholis, Homozeugos, Hookerochloa, Hordelymus, Hordeum, Hubbardia, Hubbardochloa, Humbertochloa, Hyalopoa, Hydrochloa, Hydrothauma, Hygrochloa, Hygroryza, Hylebates, Hymenachne, Hyparrhenia, Hyperthelia, Hypogynium, Hypseochloa, Hystrix, Ichnanthus, Imperata, Indocalamus, Indopoa, Indosasa, Isachne, Isalus, Ischaemum, Ischnochloa, Ischnurus, Iseilema, Ixophorus, Jansenella, Jardinea, Jouvea, Joycea, Kampochloa, Kaokochloa, Karroochloa, Kengia, Kengyilia, Kerriochloa, Kinabaluchloa, Koeleria, Lagurus, Lamarckia, Lamprothyrsus, Lasiacis, Lasiorhachis, Lasiurus, Lecomtella, Leersia, Lepargochloa, Leptagrostis, Leptaspis, Leptocarydion, Leptochloa, Leptochlo‘psis, Leptocoryphium, Leptoloma, Leptosaccharum, Leptothrium, Lepturella, Lepturidium, Lepturopetium, Lepturus, Leucophrys, Leucopoa, Leymus, Libyella, Limnas, Limnodea, Limnopoa, Lindbergella, Linkagrostis, Lintonia, Lithachne, Littledalea, Loliolum, Lolium, Lombardochloa, Lophacme, Lophatherum, Lopholepis, Lophopogon, Lophopyrum, Lorenzochloa, Loudetia, Loudetiopsis, Louisiella, Loxodera, Luziola, Lycochloa, Lycurus, Lygeum, Maclurolyra, Maillea, Malacurus, Maltebrunia, Manisuris, Megalachne, Megaloprotachne, Megastachya, Melanocenchris, Melica, Melinis, Melocalamus, Melocanna, Merostachys, Merxmuellera, Mesosetum, Metasasa, Metcalfia, Mibora, Micraira, Microbriza, Microcalamus, Microchloa, Microlaena, Micropyropsis, Micropyrum, Microstegium, Mildbraediochloa, Milium, Miscanthidium, Miscanthus, Mnesithea, Mniochloa, Molinia, Monachather, Monanthochloë, Monelytrum, Monium, Monocladus, Monocymbium, Monodia, Mosdenia, Muhlenbergia, Munroa, Myriocladus, Myriostachya, Narduroides, Nardus, Narenga, Nassella, Nastus, Neeragrostis, Neesiochloa, Nematopoa, Neobouteloua, Neohouzeaua, Neostapfia, Neostapfiella, Nephelochloa, Neurachne, Neurolepis, Neyraudia, Notochloë, Notodanthonia, Ochlandra, Ochthochloa, Odontelytrum, Odyssea, Olmeca, Olyra, Ophiochloa, Ophiuros, Opizia, Oplismenopsis, Oplismenus, Orcuttia, Oreobambos, Oreochloa, Orinus, Oropetium, Ortachne, Orthoclada, Oryza, Oryzidium, Oryzopsis, Otachyrium, Otatea, Ottochloa, Oxychloris, Oxyrhachis, Oxytenanthera, Panicum, Pappophorum, Parafestuca, Parahyparrhenia, Paraneurachne, Parapholis, Paratheria, Parectenium, Pariana, Parodiolyra, Pascopyrum, Paspalidium, Paspalum, Patzkea, Pennisetum, Pentameris, Pentapogon, Pentarrhaphis, Pentaschistis, Pereilema, Periballia, Peridictyon, Perotis, Perrierbambus, Perulifera, Petriella, Peyritschia, Phacelurus, Phaenanthoecium, Phaenosperma, Phalaris, Pharus, Pheidochloa, Phippsia, Phleum, Pholiurus, Phragmites, Phyllorhachis, Phyllostachys, Pilgerochloa, Piptatherum, Piptochaetium, Piptophyllum, Piresia, Piresiella, Plagiantha, Plagiosetum, Planichloa, Plectrachne, Pleiadelphia, Pleuropogon, Plinthanthesis, Poa, Pobeguinea, Podophorus, Poecilostachys, Pogonachne, Pogonarthria, Pogonatherum, Pogoneura, Pogonochloa, Pohlidium, Poidium, Polevansia, Polliniopsis, Polypogon, Polytoca, Polytrias, Pommereulla, Porteresia, Potamophila, Pringleochloa, Prionanthium, Prosphytochloa, Psammagrostis, Psammochloa, Psathyrostachys, Pseudanthistiria, Pseudarrhenatherum, Pseudechinolaena, Pseudobromus, Pseudochaetochloa, Pseudocoix, Pseudodanthonia, Pseudodichanthium, Pseudopentameris, Pseudophleum, Pseudopogonatherum, Pseudoraphis, Pseudoroegneria, Pseudosasa, Pseudosorghum, Pseudostachyum, Pseudovossia, Pseudoxytenanthera, Pseudozoysia, Psilathera, Psilolemma, Psilurus, Pterochloris, Ptilagrostis, Puccinellia, Puelia, Racemobambos, Raddia, Raddiella, Ratzeburgia, Redfieldia, Reederochloa, Rehia, Reimarochloa, Reitzia, Relchela, Rendlia, Reynaudia, Rhipidocladum, Rhizocephalus, Rhomboelytrum, Rhynchelytrum, Rhynchoryza, Rhytachne, Richardsiella, Robynsiochloa, Rottboellia, Rytidosperma, Saccharum, Sacciolepis, Sartidia, Sasa, Saugetia, Schaffnerella, Schedonnardus, Schenckochloa, Schismus, Schizachne, Schizachyrium, Schizostachyum, Schmidtia, Schoenefeldia, Sclerachne, Sclerochloa, Sclerodactylon, Scleropogon, Sclerostachya, Scolochloa, Scribneria, Scrotochloa, Scutachne, Secale, Sehima, Semiarundinaria, Sesleria, Sesleriella, Setaria, Setariopsis, Shibataea, Silentvalleya, Simplicia, Sinarundinaria, Sinobambusa, Sinochasea, Sitanion, Snowdenia, Soderstromia, Sohnsia, Sorghastrum, Sorghum, Spartina, Spartochloa, Spathia, Sphaerobambos, Sphaerocaryum, Spheneria, Sphenopholis, Sphenopus, Spinifex, Spodiopogon, Sporobolus, Steinchisma, Steirachne, Stenotaphrum, Stephanachne, Stereochlaena, Steyermarkochloa, Stiburus, Stilpnophleum, Stipa, Stipagrostis, Streblochaete, Streptochaeta, Streptogyna, Streptolophus, Streptostachys, Styppeiochloa, Sucrea, Suddia, Swallenia, Swallenochloa, Symplectrodia, Taeniatherum, Taeniorhachis, Tarigidia, Tatianyx, Teinostachyum, Tetrachaete, Tetrachne, Tetrapogon, Tetrarrhena, Thamnocalamus, Thaumastochloa, Thelepogon, Thellungia, Themeda, Thinopyrum, Thrasya, Thrasyopsis, Thuarea, Thyridachne, Thyridolepis, Thyrsia, Thyrsostachys, Thysanolaena, Torreyochloa, Tovarochloa, Trachypogon, Trachys, Tragus, Tribolium, Tricholaena, Trichoneura, Trichopteryx, Tridens, Trikeraia, Trilobachne, Triniochloa, Triodia, Triplachne, Triplasis, Triplopogon, Tripogon, Tripsacum, Triraphis, Triscenia, Trisetum, Tristachya, Triticum, Tsvelevia, Tuctoria, Uniola, Uranthoecium, Urelytrum, Urochloa, Urochondra, Vahlodea, Vaseyochloa, Ventenata, Vetiveria, Vietnamochloa, Vietnamosasa, Viguierella, Vossia, Vulpia, Vulpiella, Wangenheimia, Whiteochloa, Willkommia, Xerochloa, Yakirra, Ystia, Yushania, Yvesia, Zea, Zenkeria, Zeugites, Zingeria, Zizania, Zizaniopsis, Zonotriche, Zoysia, Zygochloa.

General remarks. See Clayton and Renvoize (1986); Watson and Dallwitz (1994). Clifford (1987) reviewed spikelet and floral morphology. For interactive identification and information retrieval, comprehensive html generic descriptions and better illustrations, see Watson and Dallwitz (1998 on), ‘Grass Genera of the World’, at https://www.delta-intkey.com/grass/index.htm.

Economic uses, etc. Economically the most important of families — cereals, sugarcane, fodder and pasture, alcohol, thatching, matting, bamboo construction work, etc.

Quotations.

Sea-grass, Eel-grass, Nut-grass and Knot-grass
Are not Grass.
(anon)

I am no great Nebuchadnezzar, sir;
I have not much skill in grass
(‘All’s Well’, iv., 5 - but ‘grass’ here probably means green herbaceous vegetation in general)

When Phoebe doth behold
Her silvery visage in the watery glass,
Decking with liquid pearl the bladed grass
(‘Midsummer Night’s Dream’, i., 1)

Her foes shake like a field of beaten corn,
And hang their heads with sorrow
(‘Henry the Eighth’, v., 1)

When shepherds pipe on oaten straws,
And merry larks are ploughmen’s clocks
(‘Love’s Labour’s Lost’, end - these little pipes having been used from ancient times, as mentioned by Ovid and Virgil)

His tears run down his beard, like winter’s drops
From eaves of reeds
(‘Tempest’, v., 1)

Among the tawny tasseled reed
The ducks and ducklings float and feed
(John Clare c.1834, ‘The Fens’ — Phragmites)

On either side the river lie
Long fields of barley and of rye,
That clothe the wold and meet the sky
(Tennyson, ‘The Lady of Shalott’)

Illustrations. • Le Maout and Decaisne: Avena, Triticum. • Le Maout and Decaisne: Avena, Anthoxanthum, Triticum, Monandraira (= Deschampsia), Oryza, Tripsacum. • Le Maout and Decaisne: Luziola, Anomochloa, Glyceria, Panicum, Sorghum, Coix, Gynerium. • Caryopses: Bromus, Saccharum, Zea, Lolium, Secale, Sporobolus, Tragus, Rottboellia, Stipa. • Bambusa vulgaris (as B. striata): Bot. Mag. 100 (1874). • Echinopogon intermedius: Hook. Ic. Pl. 33 (1935). • Iseilema calvum: Hook. Ic. Pl. 33 (1935). • Kinabaluchloa wrayi (as Bambusa): Hook. Ic. Pl. 23 (1894). • Habit and technical details: Bambusa. • Phyllostachys nigra: Bot. Mag. 131 (1905). • Plagiosetum refractum: Hook. Ic. Pl. 13 (1877–79). • Pooideae-Triticodae (B. Ent. compilation, 1824–35). • Rye with ergot (J.E. Sowerby, 1861). • Pooideae-Aveneae (B. Ent. compilation, 1824–35). • Pooideae-Meliceae (B. Ent. compilation, 1824–35). • Pooideae-Poeae (B. Ent compilation, 1824–35). • Pooideae Poeae, Glycerieae (B. Ent. compilation, 1824–35). • Anomochloa marantoidea (Bambusoideae, Oryzodae, Anomochloeae): Bot. Mag. 88 (1862). • Arundinoideae: Sieglingia, Molinia (B. Ent. compilation, 1824–35). • Chionochloa conspicua (as Arundo): Bot. Mag. 102 (1876). • Bouteloua: spikelet clusters (photo). • Holcus: spikelet details (photo). • Chusquea abietifolia: Bot. Mag. 111 (1885). • Pollen: Bromus, Lolium, Phalaris, Phragmites, Saccharum, Tripsacum, Zea (scanning e.m.). Assorted grass pollens, exemplifying exine sculpturing and pores. 1, Bromus rigidus; 2, Tripsacum dactyloides; 3, Zea mays; 4, Phalaris arundinacea; 5, Lolium perenne; 6, Saccharum officinarum; 7, Phragmites australis. All reproduced to the same scale except Zea, which is reduced relatively by 4.5X. From Watson and Bell (1975). • Ligule of Bromus unioloides (photo). • Ligule of a Stipa (photo). • Ligule of Phragmites (photo). • Pooid: Poa annua - abaxial epidermis of leaf blade. • Danthonioid: Rytidosperma carphoides - abaxial epidermis of leaf blade. • Chloridoid: Austrochloris dichanthoides - abaxial epidermis of leaf blade. • Panicoid: Axonopus affinis - abaxial epidermis of leaf blade. • Oryzoid: Hygroryza aristata - abaxial epidermis of leaf blade. • Andropogonoid: Hyparrhenia hirta - abaxial epidermis of leaf blade. • Silica bodies (“phytoliths”) from grass leaves. Exemplifying a range of silica-bodies from grass leaf blade epidermes. The forms are generally characteristic of species and major groups, and contribute useful information for identifying vegetative material, including fossils. They are very persistent in soil, being known to geologists as "phytoliths". For numerous illustrations and details of taxonomic distributions of the different forms, see Watson and Dallwitz (1992 onwards), The grass genera of the world: https://www.delta-intkey.com. • Pennisetum villosum - T.S. of C4 leaf blade, immunofluorescing Rubisco (Hattersley et al., 1977). • Buchloe dactyloides - transverse section of C4 leaf blade. • Aristida ramosa - T.S. C4 leaf blade with immunofluorescing Rubisco (Hattersley et al., 1977). • Alloteropsis semialata - transverse section of C4 leaf blade. • Arundinella nepalensis - transverse section of C4 leaf blade. • Triodia hubbardii - transverse section of C4 leaf blade. • Triodia pungens - transverse section of C4 leaf blade. • Entolasia stricta - transverse section of C3 leaf blade. • Phragmites australis - transverse section of C3 leaf blade. • Panicum pygmaeum - transverse section of C3 leaf blade. • Poa sieberana - transverse section of C3 leaf blade. • Panicum milioides - transverse section of C3/C4 intermediate leaf blade. • Panicum milioides - T.S. of C3/C4 leaf, Rubisco fluorescing (Hattersley et al., 1977).

We advise against extracting comparative information from the descriptions. This is much more easily achieved using the DELTA data files or the interactive key, which allows access to the character list, illustrations, full and partial descriptions, diagnostic descriptions, differences and similarities between taxa, lists of taxa exhibiting or lacking specified attributes, distributions of character states within any set of taxa, geographical distribution, genera included in each family, and classifications (Dahlgren; Dahlgren, Clifford, and Yeo; Cronquist; APG). See also Guidelines for using data taken from Web publications.

Cite this publication as: ‘Watson, L., and Dallwitz, M.J. 1992 onwards. The families of flowering plants: descriptions, illustrations, identification, and information retrieval. Version: 8th June 2026. delta-intkey.com’.

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