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Common Names in English:
Knapweed Centaurea Dealbata, Persian Cornflower, Whitewash Cornflower
Common Names in French:
The largest family of flowering plants , the Compositae (Asteraceae), comprising about 1,100 genera and more than 20,000 species and characterized by many small flowers arranged in a head looking like a single flower and subtended by an involucre of bracts. A head may consist of both ray flowers and disk flowers, as in the sunflower, of disk flowers only, as in the burdock, or of ray flowers only, as in the dandelion.
, biennials, or perennials, 20-300 cm, glabrous
. Stems erect
, or spreading
or branched. Leaves basal and cauline; petiolate
or sessile; proximal
often ± deeply lobed
in C. benedicta ), distal ± smaller, often entire, faces
glabrous or ± tomentose, sometimes also villous
, or puberulent
, often glandular-punctate. Heads discoid
, or radiant, borne singly or in corymbiform
arrays. Involucres cylindric
. Phyllaries many in 6-many series, unequal, proximal part appressed
, body margins entire. distal parts expanded into erect to spreading, usually ± dentate
, spine. tipped or spineless. Receptacles flat, epaleate, bristly
. Florets 10-many; outer usually sterile
, corollas slender and inconspicuous to much expanded, ± bilateral
; inner fertile
, corollas white to blue, pink, purple, or yellow, bilateral or radial
, often bent at junction of tubes
linear-oblong, acute; anther
, apical appendages oblong
; style branches: fused portions with minutely hairy
portions minute. Cypselae ± barrel-shaped, ± compressed
, apices entire (denticulate
benedicta ), glabrous or with fine, 1-celled hairs
, attachment scar
(with or without elaiosomes) ; pappi 0 or ± persistent
, of 1-3 series of smooth or minutely barbed
, stiff bristles
or narrow scales
. x = 8, 9, 10, 11, 12, 13, 15.
Species ca. 500: introduced ; Eurasia , n Africa, widely introduced worldwide.
Taxonomic limits of Centaurea have been controversial. The genus has great morphologic diversity , and studies have revealed much cytologic (e.g. , N. Garcia-Jacas et al. 1996) and palynologic (e.g., G. Wagenitz 1955) variation as well. During the nineteenth and twentieth centuries, various taxonomists attempted, with limited success, to divide Centaurea into smaller genera or workable infrageneric taxa. The relations of several satellite genera have been controversial as well.
Recent molecular phylogenetic studies (A. Susanna et al. 1995; N. Garcia-Jacas et al. 2000, 2001) have begun to clarify relationships within Centaurea and between Centaurea and other genera. These studies make it clear that Centaurea as traditionally defined is polyphyletic, and that generic boundaries should be realigned if monophyletic taxa are to be recognized. Some taxa traditionally included within Centaurea (e.g., the two native North American species, Centaurea americana and C. rothrockii) fall outside the redefined generic boundaries and are here treated in Plectocephalus. Others usually placed into segregate genera (e.g., Cnicus benedictus) are firmly nested within Centaurea. Because the type species of Centaurea (C. centaurium Linnaeus, an African species) falls outside the main lineage of the genus, a proposal has been made to conserve Centaurea with a different type species (W. Greuter et al. 2001), thereby maintaining the nomenclatural stability of most of the numerous species that do fall within the principal Centaurea clade.
Although several Centaurea species are widely established as members of the North American flora , and some of these are widely distributed invasive weeds , some of the taxa listed by J. T. Kartesz and C. A. Meacham (1999) are apparently waifs and not permanent members of the flora. These taxa are discussed informally immediately below.
Although Cnicus has usually been recognized as a distinctive monotypic genus, it has been merged into Centaurea by various authors (e.g., K . Bremer 1994; G. Wagenitz and F. H. Hellwig 1996) . Recent molecular systematic studies (N. Garcia-Jacas et al. 2000) provide additional evidence that it is nested within Centaurea.
Flowers: Bloom Period: April, May, June. • Flower Color: pink
Size: 18-24" tall.
Typically found at an altitude of 0 to 2,453 meters (0 to 8,048 feet).
Culture: Space 15-18" apart.
Soil: Minimum pH: 6.1 • Maximum pH: 7.8
Sunlight: Sun Exposure: Full Sun .
Moisture: Drought Tolerance: High
Temperature: Cold Hardiness: 3a, 3b, 4a, 4b, 5a, 5b, 6a, 6b, 7a, 7b, 8a, 8b. (map)
- Whittaker & Margulis,1978
- Haeckel, 1866
- Cavalier-Smith, 1981
- Sinnott, 1935 ex Cavalier-Smith, 1998
- Vascular Plants
- Brongniart, 1843
- Takhtajan, 1967
- Takhtajan Ex Reveal, 1992
- Lindley, 1833
- Giseke, 1792, nom. cons., nom. alt.
- Tribe: Cardueae ()
- Subfamily: Carduoideae ()
- Family: Compositae () - Giseke, 1792, nom. cons., nom. alt.
- Order: Asterales () - Lindley, 1833
- Superorder: Campanulanae () - Takhtajan Ex Reveal, 1992
- Subclass: Asteridae () - Takhtajan, 1967
- Class: Spermatopsida () - Brongniart, 1843
- Subphylum: Euphyllophytina ()
- Phylum: Tracheophyta () - Sinnott, 1935 ex Cavalier-Smith, 1998 - Vascular Plants
- Subkingdom: Viridaeplantae () - Cavalier-Smith, 1981
- Kingdom: Plantae () - Haeckel, 1866 - Plants
Status: Accepted Name
Comment: Data Providers: New Zealand Plant Name Database, Govaerts World Compositae Checklist A-G, IPNI, Tropicos, Euro+Med. GCC LSID: urn :lsid:compositae.org:names:0848BFAA-1FFA-42D8-9E72-75A62A9D6983
Last scrutiny: 19-Aug-09
Members of the genus Centaurea
ZipcodeZoo has pages for 82 species, subspecies, varieties, forms, and cultivars in this genus:
C. akamantis (Akamas Centaury) · C. alpestris (Greater Centaury) · C. americana (American Basketflower) · C. americana 'Aloha' (American Knapweed) · C. americana 'Jolly Joker' (American Knapweed) · C. aspera (Rough Star-Thistle) · C. atropurpurea (Centaurea) · C. bella (Knapweed) · C. benoistii (Maroon Cornflower) · C. biebersteinii (Ballast Waif Centaurea Biebersteinii) · C. bovina (Pasture Knapweed) · C. cachinalensis (Flor Del Minero) · C. calcitrapa (Big-Head Purple Starthistle) · C. calcitrapoides (Smallhead Star-Thistle) · C. cineraria (Dusty Miller) · C. cineraria 'Colchester White' (Dusty Miller) · C. crupina (Crupina) · C. cyanoides 'Blue Carpet' (Cornflower) · C. cyanus (Bachelor's Button) · C. cyanus nana 'Jubilee Gem' (Bachelors Button) · C. cyanus 'Black Ball' (Bachelors Button) · C. cyanus 'Black Boy' (Bachelors Button) · C. cyanus 'Black Gem' (Bachelors Button) · C. cyanus 'Black Magic' (Bachelors Button) · C. cyanus 'Blue Boy' (Bachelors Button) · C. cyanus 'Blue Diadem' (Bachelors Button) · C. cyanus 'Classic Blue' (Bachelors Button) · C. cyanus 'Dwarf Blue Midget' (Bachelors Button) · C. cyanus 'Frosted Queen Mix' (Bachelors Button) · C. cyanus 'Frosty Mix' (Bachelors Button) · C. cyanus 'Mauve Queen' (Bachelors Button) · C. cyanus 'Polka Dot Mix' (Bachelors Button) · C. dealbata (Knapweed Centaurea Dealbata) · C. dealbata 'Rosea' (Knapweed) · C. debeauxii (Meadow Knapweed) · C. debeauxii thuillieri (Meadow Knapweed) · C. debeauxii subsp. thuillieri (Meadow Knapweed) · C. depressa (Centaurea) · C. diffusa (Diffuse Knapweed) · C. diluta (North African Knapweed) · C. eriophora (Sand-Heath) · C. gymnocarpa (Velvet Centaurea) · C. hypoleuca DC. 'John Coutts' (Knapweed) · C. iberica (Iberian Knapweed) · C. jacea (Brown Knapweed) · C. jacea x nigra (Hybrid Knapweed Centaurea Jacea X Nigra) · C. macrocephala (Armenian Basketflower) · C. melitensis (Cockspur Thistle) · C. moncktonii (Meadow Knapweed) · C. montana (Mountain Bluet) · C. montana 'Alba' (Mountain Bluet) · C. montana 'Amethyst in Snow' (Mountain Bluet) · C. montana 'Dot Purple' (Mountain Bluet) · C. montana 'Gold Bullion' (Batchelor's Button) · C. moschata 'Dairy Maid' (Sweet Sultan) · C. moschata 'Imperialis' (Sweet Sultan) · C. moschata 'The Bride' (Sweet Sultan) · C. nigra (Black Knapweed) · C. nigrescens (Short-Fringe Starthistle) · C. orientalis (Centaurea) · C. ovina (Lilac Knapweed) · C. paniculata (Jersey Knapweed) · C. phrygia (Scandinavian Starthistle) · C. pindicola (Centaurea) · C. pulcherrima (Pink Bachelors Button) · C. 'Pulchra Major' (Bachelor's Button) · C. ragusina (Dubrovacka Zecina) · C. rothrockii (Basket Flower) · C. scabiosa (Great Starthistle) · C. solstitialis (Barnaby Star-Thistle) · C. solstitialis solstitialis (St. Barnaby's Thistle) · C. stoebe (Spotted Knapweed) · C. sulphurea (Sicilian Starthistle) · C. thuillieri (Meadow Knapweed) · C. transalpina (Alpine Knapweed) · C. trichocephala (Feather-Head Knapweed) · C. triumfetti (Squarrose Knapweed Centaurea Triumfetti) · C. triumfettii (Spreading Thistle) · C. uniflora (Single-Flower Knapweed) · C. uniflora nervosa (Singleflower Knapweed) · C. xpratensis (Meadow Knapweed) · C.'Nigra' (Bachelor Buttons)
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- A dictionary of English names of plants applied in England and among English-speaking people to cultivated and wild plants, trees, and shrubs, by William Miller; in two parts, English-Latin and Latin-English. London, J. Murray, 1884. url p. 24.
- A first report on the relations between climates and crops. By Cleveland Abbe. Washington [D.C.]: Govt. Print. Off., 1905. url p. 198.
- Alien flora of Britain. London, West, Newman, 1905. url p. 108.
- Brooklyn Botanic Garden record. 25 1936 [Brooklyn]: Brooklyn Botanic Garden, 1912-44. url p. 5.
- Bulletin of miscellaneous information /Royal Botanic Gardens, Kew. 1915 London: H.M. Stationery Office, 1900-1941. url p. 294, p. 295, p. 309.
- Cassell's dictionary of practical gardening; an illustrated encyclopædia of practical horticulture for all classes; ed. by Walter P. Wright. London, Cassell and company, limited, 1902. url p. 185.
- Colour in my garden, by Louise Beebe Wilder. Illustrated in colour, by Anna Winegar. Garden City, N.Y., Doubleday, Page, 1918. url p. 227, p. 283, p. 384, p. 385, p. 394, p. 395, p. 397.
- Cyclopedia of American horticulture, comprising suggestions for cultivation of horticultural plants, descriptions of the species of fruits, vegetables, flowers and ornamental plants sold in the United by L. H. Bailey. .. assisted by William Miller. .. and many expert cultivators and botanists. London: The Macmillan company, 1909. url p. 737.
- Flora of the U.S.S.R. [Springfield, Va.: Israel Program for Scientific Translations; 1968- url p. 418.
- Florists' review Chicago: Florists' Pub. Co. url , , .
- Garden and forest; a journal of horticulture, landscape art and forestry. New York: The Garden and forest publishing co., 1888-97. url p. 307.
- Gardening. Chicago, the Gardening Co., 1892-1925. url p. 147, p. 307, p. 314.
- Hand-list of herbaceous plants cultivated in the Royal Botanic Gardens. London, Printed for H. M. Stationery Off. by Darling, 1902. url p. 265.
- Handbook of flower pollination based upon Hermann Müller's work 'The fertilisation of flowers by insects'; tr. by J.R. Ainsworth Davis. Oxford, Clarendon Press, 1906. url p. 569.
- Hardy flowers. Descriptions of upwards of thirteen hundred of the most ornamental species, with directions for their arrangement, culture, etc.. .. By W. Robinson. London, Macmillan, 1878. url p. 87.
- Horticulture. Boston, Mass.: Horticulture Pub. Co., c1904- url p. 149, p. 451.
- International catalogue of scientific literature [Sect.] M. Botany: 1st -14th annual issues, 1901-1914. London: Published for the International Council by the Royal Society of London, 1901-1919. url .
- Johnson's Gardeners' dictionary and cultural instructor. London, A. T. De La Mare printing and publishing co., ltd. url p. 659.
- Nicholson, G. The illustrated dictionary of gardening: a practical and scientific encyclopædia of horticulture for gardeners and botanists /edited by George Nicholson; assisted by J.W.H. Trail. .. and J. Garrett. .. 9 1884 London: L.U. Gill, -88. url p. 433.
- Papers and proceedings of the Royal Society of Tasmania. Hobart, Tasmania, The Society. url p. 106.
- Practical floriculture; a guide to the successful cultivation of florists' plants, for the amateur and professional florist. New York, Orange Judd company, 1882. url p. 249, p. 249.
- The American florist: a weekly journal for the trade. Chicago: American Florist Company, [1885-1931] url p. 33, p. 469, p. 492, p. 553, p. 679.
- The Annals and magazine of natural history; zoology, botany, and geology being a continuation of the Annals combined with Loudon and Charlesworth's Magazine of Natural History. London, Taylor and Francis, Ltd. url p. 41.
- The English flower garden and home grounds: design and arrangement shown by existing examples of gardens in Great Britain and Ireland, followed by a description of the plants, shrubs, and trees for the open-air garden and their culture / by W. Robinson. London: J. Murray, 1911. url p. 486.
- The Floral world and garden guide. London, Groombridge and Sons, 1858-1880. url p. 193.
- The Florists' exchange: a weekly medium of interchange for florists, nurserymen, seedsmen and the trade in general. New York, N.Y.: [A.T. De la Mare Ptg. and Pub. Co., url p. 208, p. 401, p. 666.
- The Garden: an illustrated weekly journal of gardening in all its branches. London: [s.n., url , , p. 105, p. 111, p. 16, p. 346, p. 491.
- The Gardeners' chronicle: a weekly illustrated journal of horticulture and allied subjects. London: [Gardeners Chronicle], 1874-1955. url p. 144, p. 231, p. 330, p. 346, p. 371, p. 401, p. 422, p. 487, p. 682, p. 734, p. 787.
- The Illustrated dictionary of gardening: a practical and scientific encyclopaedia of horticulture for gardeners and botanists / edited by George Nicholson. ..; assisted by J.W.H. Trail. .. and J. Garrett. ... London: L. Upcott Gill; 1887-1889. url p. 367, p. 382, p. 411, p. 422.
- The complete home landscape, by Arthur J. Jennings, in collaboration with Leonard H. Johnson. New York, A. T. De La Mare, 1924. url p. 161, p. 165, p. 169.
- The garden month by month; describing the appearance, color, dates of bloom, height and cultivation of all desirable, hardy herbaceous perennials for the formal or wild garden with additional lists of aquatics, vines, ferns, et by Mabel Cabot Sedgwick assisted by Robert Cameron with over two hundred half-tone engravings from photographs of growing plants, and a chart in colors. New York, F.A. Stokes Co.,  url .
- The garden's story, or Pleasures and trials of an amateur gardener, New York, D. Appleton and company, 1889. url p. 331.
- The garden's story: or, Pleasures and trials of an amateur gardener / by George H. Ellwanger. .. New York: Appleton, 1891. url p. 341.
- The subtropical garden, or, Beauty of form in the flower garden / by W. Robinson London: J. Murray, 1879 url p. 113.
- The subtropical garden: or, Beauty of form in the flower garden / by W. Robinson. London: J. Murray, 1891. url p. 113.
- The wild garden; or, Our groves & shrubberies made beautiful. .. London, J. Murray, 1870. url .
- Town gardening / by Mary Hampden. New York, C.Scribner's sons, 1922 url p. 23.
- Transactions of the Massachusetts Horticultural Society. [S.l.: s.n.], 1843-1920. url p. 269.
- Travels in the central Caucasus and Bashan; including visits to Ararat and Tabreez and ascents of Kazbek and Elbruz. By Douglas W. Freshfield. London: Longmans, Green, & co., 1869. url p. 504.
- Garcia-Jacas, N., A. Susanna, V. Mozaffarian, and R. Ilarslan. 2000. The natural delimitation of Centaurea (Asteraceae: Cardueae): ITS sequence analysis of the Centaurea jacea group. Pl. Syst. Evol. 223: 185199.
- Moore, R. J. 1972. Distribution of native and introduced knapweeds (Centaurea) in Canada and the United States. Rhodora 74: 331346.
- Roché, B. F. and C. T. Roché. 1991. Identification, introduction, distribution, ecology, and economics of Centaurea species. In: L. F. James et al., eds. 1991. Noxious Range Weeds. Boulder, San Francisco, and Oxford. Pp. 274291.
- Wagenitz, G. 1955. Pollenmorphologie und Systematik in der Gattung Centaurea L. s.l. Flora 142: 213279.
- Brands, S.J. (comp.) 1989-present. The Taxonomicon. Universal Taxonomic Services, Zwaag, The Netherlands. Accessed March 27, 2012.
Accessed through GBIF Data Portal November 19, 2007:
- Missouri Botanical Garden, Missouri Botanical Garden
- Natural History Museum, University of Oslo, Vascular Plant Herbarium, Oslo
- The Swedish Museum of Natural History
- , Herbarium of Oskarshamn
- The Swedish Museum of Natural History
- , Plants
- Biodiversity Heritage Library NamebankID: 2676195
- Catalogue of Life Accepted Name Code: Ast-7581
- Global Biodiversity Information Facility Taxonkey: 13735611
- Globally Unique Identifier: urn:lsid:ipni.org:names:190330-1
- GRIN Nomen Number: 100749
- Integrated Taxonomic Information System (ITIS) Taxonomic Serial Number (TSN): 565055
- U.S.D.A. Plant Symbol: CEDE15
- Zipcode Zoo Species Identifier: 28383
- David J. Keil, Jörg Ochsmann "Centaurea". in Flora of North America Vol. 19, 20 and 21 Page 52, 57, 58, 67, 83, 84, 96, 171, 172, 176, 177, EFloras.org. [back]
- Mean = 295.800 meters (970.472 feet), Standard Deviation = 615.520 based on 15 observations. Altitude information for each observation from British Oceanographic Data Centre. [back]