Digitaria humifusa

• Interesting Facts
• Description
• Taxonomy
• Similar Species
• More Info
• Further Reading
• Notes

Interesting Facts

Description

Genus Digitaria

Annual or perennial . Culms erect or decumbent , occasionally stoloniferous . Leaf blades linear or linear-lanceolate; ligule membranous. Inflorescence of digitately arranged racemes , sometimes on a short axis or with secondary branchlets , very rarely paniculate ; spikelets usually in groups of 2-3(-4), imbricate to effuse, the latter often on notably long and unequal pedicels. Spikelets puberulous to villous , typically in stripes between the well-defined veins, rarely glabrous ; lower glume absent or reduced to a little scale up to 1/4 spikelet length; upper glume variable; lower lemma usually ± equal to spikelet; upper floret pallid to black, apex subacute to acuminate, rarely apiculate . x = 9.

About 250 species:tropical and warm-temperate regions of the world; 22 species (three endemic) in China.

Digitaria has been traditionally divided on the nature of the spikelet hairs, which may be clavate , capitate, verrucose (warty, appearing beaded), or with crooked tips . As good magnification is required to see these features, the grouping of the spikelets on the raceme is a more practical aid to identification. Many species have regularly paired spikelets, which present no difficulty. In those species where the spikelets are grouped in clusters of 3 or more, care must be taken, as often the longest pedicel of a group is partially fused to the rachis so that the spikelets appear alternately paired and single, or sometimes one spikelet may be vestigial, or the spikelets may be paired toward the raceme tips.

Many species are very variable in spikelet pubescence and lemma nervation, even within a single raceme. Additionally, there are a number of complexes of intergrading species, so intermediates may occasionally be encountered. This has led to the publication of many superfluous names .[1]

Taxonomy

Similar Species

Members of the genus Digitaria

ZipcodeZoo has pages for 53 species, subspecies, varieties, forms, and cultivars in this genus:

D. abyssinica (African Couchgrass) · D. arenicola (Fall Witchgrass) · D. argillacea (Tropical Crabgrass) · D. bicornis (Asia Crabgrass) · D. californica (Arizona Cottontop) · D. ciliaris (Fingergrass) · D. cognata (Carolina Cottontop) · D. cognata var. cognata (Carolina Crabgrass) · D. cognata var. pubiflora (Carolina Crabgrass) · D. cruciata (Crabgrass) · D. diagonalis (Brown-Seeded Finger Grass) · D. didactyla (Crabgrass) · D. dolichophylla (Caribbean Crabgrass) · D. eggersii (Eggers' Crabgrass) · D. eriantha (Pangola Grass) · D. eriantha subsp. eriantha (Crabgrass) · D. eriantha subsp. pentzii (Woolly Fingergrass) · D. exilis (Fonio) · D. filiformis (Slender Crabgrass) · D. floridana (Florida Crabgrass) · D. fuscescens (Yellow Crabgrass) · D. gracillima (Long-Leaf Crabgrass) · D. henryi (Henry´s Crabgrass) · D. hitchcockii (Short-Leaf Crabgrass) · D. horizontalis (Jamaica Crabgrass) · D. iburua (Black Fonio) · D. insularis (Sourgrass) · D. ischaemum (Small Crabgrass) · D. ischaemum var. ischaemum (Small Crabgrass) · D. longiflora (India Crabgrass) · D. milanjiana (Madagascar Crabgrass) · D. natalensis (Natal Crabgrass) · D. nuda (Naked Crabgrass) · D. panicea (Millet Crabgrass) · D. patens (Texas Cottontop) · D. pauciflora (Florida Pineland Crabgrass) · D. pubiflora (Carolina Crabgrass) · D. radicosa (Trailing Crabgrass) · D. sanguinalis (Crabgrass) · D. seriata (Crabgrass) · D. serotina (Blanket Crabgrass) · D. setigera (East Indian Crabgrass) · D. setivalva (Crabgrass) · D. similis (Roadside Crabgrass) · D. simpsonii (Isle-Of-Pines Crabgrass) · D. swalleniana (Swallen's Crabgrass) · D. ternata (Black-Seeded Crabgrass) · D. texana (Texas Crabgrass) · D. tomentosa (Woolly Crabgrass) · D. umfolozi (Crabgrass) · D. velutina (Annual Couchgrass) · D. villosa (Shaggy Crabgrass) · D. violascens (Violet Crabgrass)

More Info

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Further Reading

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• A compendium of the English flora. London, Longman, Rees, Orme, Brown, Green & Longman, 1836. url p. 19.
• A manual of weeds, with descriptions of all the most pernicious and troublesome plants in the United States and Canada, their habits of growth and distribution, with methods of control, by Ada E. Georgia. .. with 385 illustrations by F. Schuyler Mathews. .. New York: The Macmillan Company, 1916, c1914. url p. 27, p. 577.
• A natural history of British grasses / by E.J. Lowe. London: John C. Nimmo, 1891. url p. 221.
• A new London flora; or, Handbook to the botanical localities of the metropolitan districts. Compiled from the latest authorities, and from personal observations. London, Hardwick and Bogue, 1877. url p. 153, p. 156, p. 20.
• A student's text-book of botany, by Sydney H. Vines. With 483 illustrations. London, Macmillan & co., 1896. url .
• A text-book of grasses with especial reference to the economic species of the United States, by A. S. Hitchcock. New York, Macmillan, 1914. url p. 269.
• A text-book of grasses: with especial reference to the economic species of the United States / by A.S. Hitchock. New York: Macmillan, 1914. url p. 181, p. 269.
• An account of the flowering plants, ferns and allies of Harleston. With a sketch of the geology, climate, and natural characteristics of the neighbourhood. Compiled and edited by Francis William Galpin. To which are added Observations on the birds of the district, by Charles Candler. London, Bartlett, 1888. url p. 116.
• An elementary text-book of botany, by Sydney H. Vines. .. London: S. Sonnenschein & co., lim.;1898. url p. 489.
• An illustrated flora of the northern United States, Canada and the British possessions: from Newfoundland to the parallel of the southern boundary of Virginia, and from the Atlantic Ocean westward to the 102d meridian / by Nathaniel Lord Britton and Addison Brown. New York: C. Scribner's Sons, 1896-1898. url p. 111.
• Annotated list of the ferns and flowering plants of New York state, by Homer D. House. Albany, The University of the state of New York, 1924. url p. 69.
• Annual report / Albany: University of the State of New York, 1902-1918. url .
• Annual report of the Commissioner of Agriculture. .. Albany: State of New York, Dept. of Agriculture, 1894-1911. url p. 745.
• Annual report of the Maine Agricultural Experiment Station. [Orono, Me.: Maine State College, 1885-1953. url p. 195.
• British entomology; being illustrations and descriptions of the genera of insects found in Great Britain and Ireland: containing coloured figures from nature of the most rare and beautiful species, and in many instances By John Curtis. London, Printed for the author, 1823-40. url p. 20.
• British grasses: an introduction to the study of the Gramineae of Great Britain and Ireland / 1867 London: Reeve & co., 1867 url p. 106.
• Britton, N. L. (ed.). North American flora. [New York]New York Botanical Garden. url p. 1036.
• Bulletin of the Torrey Botanical Club. 22 1895 New York: Torrey Botanical Club, 1870-1996 url p. 420.
• Bulletin of the U.S. Department of Agriculture. [Washington, D.C.?]: Supt. of Docs., G.P.O., 1913-1923. url p. 218.
• Catalogue of the flowering plants and ferns of Connecticut growing without cultivation / by Charles Burr Graves. .. [et al.]; Committee of the Connecticut Botanical Society. Hartford: Printed for the State Geological and Natural History Survey, 1910. url p. 49.
• Contributions from the United States National Herbarium 46 2003 Washington, D.C.: Smithsonian Institution Press, 1890- url p. 203, p. 204, p. 24, p. 362, p. 476, p. 612, p. 73.
• Cybele Britannica: or British Plants and their geographical relations. London, 1847-59. url p. 149, p. 451.
• Flora metropolitana; or, Botanical rambles within thirty miles of London, being the results of numerous excursions made in 1833, 34, 35. .. intended for the student in practical botany. .. London, S. Highley, 1836. url p. 44.
• Flora of Indiana, by Charles C. Deam. Indianapolis, Wm. B. Burford printing co., contractor for state printing and binding, 1940. url p. 148.
• Flora of Japan: in English: combined, much revised and extended translation / by the author of his Flora of Japan (1953) and Flora of Japan, Pteridophyta (1957); edited by Frederick G. Meyer and Egbert H. Walker. Washington: Smithsonian Institution, 1965. url p. 183.
• Flora of Nebraska; a list of the conifers and flowering plants of the state with keys for their determination. Plainview, Neb.[c1912] url .
• Flora of Sussex; or a list of the flowering plants & ferns found in the county of Sussex, with localities of the less common species. London, Simpkin [et al.]1907. url p. 143.
• Flora of the District of Columbia and vicinity. By A.S. Hitchcock and Paul C. Standley, with the assistance of the botanists of Washington. WashingtonGovt. print. off.1919 url p. 73.
• Flora of the Indiana dunes, a handbook of the flowering plants and ferns of the lake Michigan Coast of Indiana and of the Calumet District, by Donald Culross Peattie. Chicago, Field Museum of Natural History, 1930. url p. 53.
• Flora of the U.S.S.R. 2 1934 [Springfield, Va.: Israel Program for Scientific Translations; 1968- url p. 25.
• Grasses of North America for farmers and students. .. / by W.J. Beal. Lansing: W.J. Beal, 1887-1896. url p. 110.
• Handbook of grasses, treating of their structure, classification, geographical distribution and uses, also describing the British species and their habitats. London, Macmillan, 1910. url .
• Handbook of the British flora: a description of the flowering plants and ferns indigenous to, or naturalized in, the British Isles. For the use of beginners and amateurs. By George Bentham. London: L. Reeve & Co., 1920. url p. 510.
• Hardwicke's science-gossip: an illustrated medium of interchange and gossip for students and lovers of nature. London: Robert Hardwicke, 1866- url , p. 224, p. 286.
• Illustrations of the British flora: a series of wood engravings, with dissections, of British plants. London, L. Reeve, 1919. url .
• Journal of botany, British and foreign. 1905 London: Robert Hardwicke, 1863-1942. url p. 101, p. 360.
• List of Pteridophyta and Spermatophyta growing without cultivation in northeastern North America. Prepared by a Committee of the Botanical Club, American Association for the Advancement of Science. New York, 1894. url p. 31.
• Manual of British botany, containing the flowering plants and ferns. Arranged according to the natural orders. London, J. Van Voorst, 1851. url .
• Manual of British grasses / 1907 London: Simpkin, Marshall, Hamilton, Kent, [1907] url list of british grasses, page 11, chapter II.
• Manual of the grasses of the United States / by A.S. Hitchcock. Washington: U.S. G.P.O., 1935. url p. 836.
• Memoirs of the Torrey Botanical Club. 5 1893 - 18 Durham, N.C.: Published for the Club by the Seeman Printery, 1889- url p. 31.
• Miscellaneous papers on the botany of Michigan, by C. K. Dodge. Prepared under the direction of Alexander G. Ruthven. Published as a part of the Annual report of the Board of Geological Survey for 1920. Lansing, Mich., Wynkoop Hallenbeck Crawford, State Printers, 1921. url p. 134, p. 22, p. 83.
• Miscellaneous publications / University of Michigan, Museum of Zoology. Ann Arbor, Mich.: The University, 1916- url p. 9.
• Museum bulletin / Albany, N.Y.: University of the State of New York, 1908-1916. url p. 17.
• Natural history of New York. Albany: D. Appleton: 1842-1894. url p. 423, p. 423.
• Observations on the flowering plants, ferns and fern allies growing wild in Marquette County, Michigan, in 1916 and 1917, especially in the vicinity of the Huron Mountain Club. Ann Arbor, Michigan, Published by the University, 1918. url .
• Report of the Michigan Academy of Science. Lansing, Mich.: The Academy, 1904-1916. url p. 142.
• Report of the State Botanist. Albany, N.Y.: University of the State of New York, 1898-1925. url .
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• The Canadian field-naturalist. 62 1948 Ottawa, Ottawa Field-Naturalists' Club. url p. 187, p. 81.
• The Journal of the Linnean Society. Botany. 36 1903-05 London: the Society: Longman, Green, Longman, Roberts & Green: ||Williams and Norgate, 1865-1968. url p. 324.
• The Natural history of the Toronto Region, Ontario, Canada / edited by J.H. Faull. -- Toronto: Canadian Institute, 1913. url .
• The Ottawa naturalist. Ottawa, Ottawa Field-Naturalists' Club. url p. 152.
• The Phytologist: a botanical journal. London, William Pamplin, 1855-1863. url p. 370, p. 459.
• The Phytologist: a popular botanical miscellany. London, John van Voorst, 1844-56. url p. 1076, p. 845.
• The flora of British India. London, L. Reeve & Co., 1875-97. url .
• The flora of Suffolk a topographical enumeration of the plants of the county, showing the results of former observations and of the most recent researches / by W.M. Hind; assisted by Churchill Babington; with an introductory chapter of the geology, climate and meteorology of Suffolk by Wheelton Hind. London: Gurney and Jackson, 1889. url p. 471.
• The flora of the Alps being a description of all the species of flowering plants indigenous to Switzerland; and of the Alpine species of the adjacent mountain districts of France, Italy, & Austria including the Pyrenees / by Alfred W. Bennett. London: J.C. Nimmo, 1896. url p. 179.
• The flora of the Alps; being a description of all the species of flowering plants indigenous to Switzerland; and of the Alpine species of the adjacent mountain districts of France, Italy, & Austria including the Pyrenees, London, J. C. Nimmo, 1896-1900. url .
• The gardener's magazine and register of rural & domestic improvement. London: Longman, Rees, Orme, Brown and Green, 1826-1844. url p. 291.
• The genera of grasses of the United States: with special reference to the economic species / by A.S. Hitchcock. Washington, D.C.: U.S. Dept. of Agriculture, 1920. url p. 218.
• The grasses of Britain / by Richard Parnell; drawn and engraved by the author. Edinburgh: W. Blackwood, 1845. url , .
• The grasses of Great Britain, London, R. Hardwicke[1861] url , .
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• The grasses of Illinois, by Edna Mosher. Urbana, Ill., 1918. url p. 282.
• The natural history of the Toronto region, Ontario, Canada / edited by J.H. Faull. Toronto: Canadian Institute, 1913. url p. 104.
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• The student's flora of the British islands / by Sir J.D. Hooker. London: Macmillan, 1884. url p. 544.
• The weed flora of Iowa / [by L. H. Pammel; with the collaboration of Charlotte M. King. .. et al.] Des Moines: Iowa Geological Survey, 1913. url p. 10, p. 11, p. 408, p. 409, p. 505, p. 506, p. 714, p. 789, p. 883.
• The weed flora of Iowa Des Moines, Iowa geological survey, 1913. url , , , , , , , .
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• The wild-flowers of Selborne and other papers by John Vaughan. London, J. Lane, 1906. url p. 83, p. 83.
• Topographical botany: being local and personal records towards shewing the distribution of British plants traced through the 112 counties and vice-counties of England, Wales, and Scotland. London, B. Quaritch, 1883. url .
• Torreya. Burlington, Vt., Torrey Botanical Club, 1901-1945. url p. 188, p. 219, p. 226, p. 252.
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• Transactions of the Illinois State Academy of Science. Springfield, Ill., Illinois State Academy of Science [etc.] url p. 172, p. 178.
• Weeds of the farm and garden, by L.H. Pammel. .. New York, Orange Judd, 1912. url p. 139, p. 140, p. 33.

Notes

Contributors

• Brands, S.J. (comp.) 1989-present. The Taxonomicon. Universal Taxonomic Services, Zwaag, The Netherlands. Accessed January 10, 2012.

Identifiers

• Biodiversity Heritage Library NamebankID: 10752365
• Global Biodiversity Information Facility Taxonkey: 15754045
• Globally Unique Identifier: urn:lsid:ipni.org:names:398880-1
• Zipcode Zoo Species Identifier: 733575

Footnotes

1. Shou-liang Chen & Sylvia M. Phillips "Digitaria". in Flora of China Vol. 22 Page 1, 500, 539. Published by Science Press (Beijing) and Missouri Botanical Garden Press. Online at EFloras.org. [back]

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