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Common Names in English:
Swamp Thistle, Dunce-Nettle, Horsetops
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
, 5-400 cm, spiny
. Stems (1-several) erect
, branched or simple
, sometimes narrowly spiny-winged. Leaves basal and cauline; finely bristly-dentate to coarsely dentate
or 1-3 times pinnately lobed
, teeth and lobes
green and glabrous
or densely gray-canescent, usually eglandular
. Heads discoid
, borne singly, terminal
and in distal axils, or in racemiform
, or corymbiform
arrays. ( Peduncles with ± reduced leaflike bracts.) Involucres cylindric
or spheric, (1-6 Ã—) 1-8 cm. Phyllaries many in 5-20 series, subequal
or weakly to strongly, outer and middle
and apices spreading
to erect, usually spine-tipped, innermost usually with erect, flat, often twisted, entire or dentate, usually spineless apices (distal portion of phyllary
in many species with elongate
, usually milky
in fresh material
but dark brown to black when dry) . Receptacles flat to convex
, epaleate, covered with tawny
to white bristles
. Florets 25-200+; corollas white to pink, red, yellow or purple, ± bilateral
long, slender, distally bent, throats
short, abruptly expanded. cylindric, lobes linear
bases sharply short-tailed, apical appendages
linear-oblong; style tips
elongate (as measured in descriptions
including the slightly swollen nodes, long cylindric fused portions of style branches and very short distinct portions) . Cypselae ovoid, ± compressed
, with apical rims, smooth
, not ribbed
, glabrous, basal attachment scars
; pappi persistent
or falling in rings
, in 3-5 series of many flattened, plumose
bristles or plumose, setiform scales (longer
bristles shorter than corollas except in C. foliosum and C.
arvense) . x = 17.
Species ca. 200: North America, Eurasia , n Africa.
Only three genera in Cynareae are represented by native species in the New World, and of these Cirsium is by far the most widely distributed and diverse . Native species of Cirsium range from sea level to alpine and from boreal regions of Canada to the tropics of Central America. Members of the genus occur in a myriad of habitats including swamps , meadows, forests , prairies, sand dunes, and deserts.
Preliminary molecular phylogenetic studies by D. G. Kelch and B . G. Baldwin (2003) indicated that this diversity is the product of a rapid evolutionary diversification based upon a single initial introduction from Eurasia. Relationships among the North American species are apparently complex , and molecular studies have only begun to provide an outline of phylogeny for these plants . Although there has been a remarkable evolutionary and morphologic diversification in North American Cirsium, it has not been accompanied by very much divergence in the base sequences of genes commonly used to elucidate phylogenetic relationships. This suggests either that the diversification has been very rapid or that genetic markers in North American Cirsium mutate more slowly than in most other lineages .
Chromosomal diversification has accompanied the morphologic radiation of North American Cirsium. Many New World Cirsium species share the chromosomal base number of x = 17 that also predominates in most Eurasian species. Among the North American thistles, however, is a mostly descending dysploid series with chromosome numbers ranging from n = 18 to n = 10. Very few instances of polyploidy are known among New World Cirsium.
Cirsium species of remarkably different morphologies often are able to hybridize . Although in some hybrid combinations fertility is reduced, in others the formation of complex hybrid swarms indicates a lack of breeding barriers and the potential for emergence of novel character combinations. In the absence of adequate sampling and field observations, hybrids may go unrecognized, treated as distinct taxa or as variants of non-hybrid taxa, or left occupying the indeterminate folders of herbaria. In other cases hybridization has been invoked without much evidence as an explanation for Cirsium variants encountered in herbaria or in the field. Hybrid combinations are listed herein when evidence is convincing. Additional hybrids are likely to be found where the ranges of Cirsium species overlap. I have seen no documentation of hybridization between native American Cirsium species and introduced Eurasian taxa.
Much of the geographic range currently occupied by New World Cirsium species was greatly affected by the events of the Quaternary . Large areas were glaciated and other areas were vastly different during glacial episodes. The ancestors of thistles that currently occupy the high mountains of western North America were undoubtedly displaced elevationally and/or latitudinally during the recurrent glacial and interglacial episodes of the Pleistocene . Taxa that are currently isolated may have been in contact during glacial episodes with the opportunity for hybridization and genetic interchange. Episodes of prehistoric hybridization may have led to some of the character combinations found in modern American thistles, particularly in the western half of the continent. Current isolation and localized selection or genetic drift apparently have promoted differentiation of populations separated on mountaintop islands.
One of the most challenging aspects for a taxonomist studying New World Cirsium is the presence of species complexes that are apparently evolutionary works in progress. Some of the thistles, especially in the mountainous western part of North America, are frustratingly polymorphic with much overlapping variability and intergradation of characters. Early taxonomists, basing their work on a limited sampling of the morphologic diversity, named many of the forms as species, and the literature is rife with species names . The infilling that results from more collectors visiting more localities within the ranges of these complexes has blurred the boundaries between many of the proposed species and often added forms that do not "fit" the characteristics of named species. As I faced the challenges of preparing this treatment, I recognized that maintaining some of the named entities as species would, for consistency, require a further proliferation of species names. I have chosen to go the other way. Instead of proposing yet more ill-defined microspecies, I have chosen to recognize that the groups in question are rapidly evolving, only partially differentiated assemblages of races that have not reached the level of stability that is usually associated with the concept of species. Certainly much of such variation within the genus deserves a level of taxonomic recognition, or at least should be mentioned, but for those assemblages I think it much more prudent to recognize varieties -- entities that may be expected to freely intergrade -- rather than species.
Many problems remain to be worked out in North American Cirsium. Further investigation will undoubtedly reveal the need for refinement or major revision within some of the species groups. Studies that focus on variation within and among populations and on the biological basis for the variations are much needed. The field is open and the challenges are many.
Preparation of a workable key to Cirsium species has been frustratingly difficult. Extensive and overlapping ranges of variation in morphologic characteristics often require that a species be keyed two or more times. The resulting key is longer and more complex than I would prefer, and I have no doubt ignored, overlooked, or been completely unaware of variants that will not key out. Caveat clavitor!
The reputation of Cirsium has suffered greatly as a result of the introduction to North America of a few invasive weedy species from Eurasia. Cirsium vulgare (bull thistle) and C. arvense (Canada thistle€”a misnomer) have long been despised as noxious weeds . In recent years C. palustre (European swamp thistle) has joined their ranks . Additionally, weedy Eurasian species of Carduus, Onopordum, Centaurea, etc. , add to the public perception that all thistles are bad. Most North American native Cirsium are not at all weedy, and many are strikingly attractive plants. All are spiny plants that command respect, but they deserve a better reputation as one of North America€™s evolutionary success stories.
Native Cirsium species have come under threat from biocontrol programs instituted to suppress populations of weedy introduced thistles. Beginning in 1968 the seedhead weevil Rhinocyllus conicus has been widely introduced in various areas of the United States and Canada, primarily to control weedy species of Carduus. S. M. Louda et al. (1997) reported that R. conicus has crossed over to several native species of Cirsium. They observed that the number of viable cypselae in infested heads was greatly reduced; e.g. , heads of C. canescens infested by R. conicus produced 14.1 percent of the number of viable cypselae as in uninfested heads. Not all taxa are impacted as much as C. canescens, particularly those with later flowering phenology (Louda 1998) . R. W. Pemberton (2000) reported that 22 Cirsium taxa in North America are known hosts of R. conicus. I suspect that the number is higher. During my field work I have observed that the heads of many Cirsium species are heavily parasitized, although I have not determined which of these are infested by R. conicus and which by native seedhead parasites. The long-term impacts of R. conicus and other biocontrol agents on native thistles, particularly rare taxa, remain to be determined.
Species Cirsium muticum
Biennials, 30-230 cm; taproots
. Stems single,
, distally sometimes
; branches few-many, ascending
. Leaves ovate
to broadly elliptic
, 15-55 × 4-20 cm, deeply pinnatifid
to 7/8 to midribs
to lanceolate, acute to acuminate,
irregularly few toothed
, main spines 2-3 mm, abaxial
thinly tomentose or glabrate, villous with septate trichomes on the
faces thinly pilose
; basal usually absent at flowering,
tapered; principal cauline petiolate
or sessile, gradually reduced distally, bases sometimes ±
, not decurrent; distal cauline bractlike with narrowly linear
lobes, often spinier than the proximal
. Heads 1-many in ±
arrays. Peduncles 0-15 cm
(sometimes overtopped by distal cauline leaves, not subtended by
of bracts.. Involucres ovoid
, 1.7-3 × 1-3 cm, arachnoid
in 8-12 series, strongly imbricate, dull
green with darker subapical
, ovate (outer) to linear-lanceolate (inner), abaxial faces
with narrow glutinous
, outer and middle
, bodies minutely
, apices obtuse
to acute, spines erect (sometimes appearing
in dry specimens), 0-0.5 mm; apices of inner phyllaries
straight or ± flexuous
, flattened. Corollas lavender
or purple (white), 16-32 mm, tubes
7-15 mm, throats
4.5-10 mm (noticeably
wider than tubes., lobes 4-8 mm; style tips
dark brown, 4.5-5.5 mm, apical collars
yellow, 0.3 mm; pappi
12-20 mm. 2n = 20, 21, 22, 23, 30. [source]
Cirsium muticum is very widely distributed across the eastern half of North America from the prairies of southeastern Saskatchewan across southern Canada to Newfoundland and south in the United States from North Dakota and Maine to southeastern Texas and northern Florida. It is more common in the northern half of this range and extends from the coastal plain to the Appalachian highlands. The widely scattered populations in coastal lowlands in the southern United States may be relicts of the glacial distribution of the species. [source]
Cirsium muticum is known to hybridize with C. discolor (discussed thereunder) and C. flodmanii. Draining and modification of wetlands have affected populations of C. muticum in some areas. [source]
Flowers: Bloom Period: May, June, July, August, September. • Flower Color: magenta, pink
Size: 36-48" tall.
Wet soil in meadows, prairies, marshes, swamps , bogs , open woods ; 0-1500+ m .
Typically found at an altitude of 0 to 1,092 meters (0 to 3,583 feet).
Sunlight: Sun Exposure: Full sun .
- Whittaker & Margulis,1978
- Haeckel, 1866
- Cavalier-Smith, 1981
- Sinnott, 1935 ex Cavalier-Smith, 1998
- Vascular Plants
- Brongniart, 1843
- Takhtajan, 1967
- Takhtajan Ex Reveal, 1992
- 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
Carduus muticus (Michaux) Persoon • Carduus muticus (Michx.) Pers. • Cirsium bigelovii Dc. • Cirsium muticum var. monticola (Fernald) Fernald • Cirsium muticum var. subpinnatifidum (Britt.) Fern.
Status: Accepted Name
Comment: Data Providers: Govaerts World Compositae Checklist A-G, IPNI, Tropicos. GCC LSID: urn :lsid:compositae.org:names:1A63FE6D-C2CE-46D3-8322-A84BDCB7D914
Last scrutiny: 12-Aug-09
Members of the genus Cirsium
ZipcodeZoo has pages for 146 species, subspecies, varieties, forms, and cultivars in this genus. Here are just 100 of them:
C. altissimum (Roadside Thistle) · C. amblylepis (Mt. Tamalpais Thistle) · C. andersonii (Anderson's Thistle) · C. andrewsii (Franciscan Thistle) · C. araneans (Jeweled Thistle) · C. arcuum (Powderpuff Thistle) · C. aridum (Cedar Rim Thistle) · C. arizonicum (Arizona Thistle) · C. arizonicum var. arizonicum (Arizona Thistle) · C. arizonicum var. nidulum (Arizona Thistle) · C. arvense (Californian Thistle) · C. barnebyi (Barneby's Thistle) · C. brevifolium (Palouse Thistle) · C. brevistylum (Clustered Thistle) · C. calcareum (Cainville Thistle) · C. californicum var. californicum (California Thistle) · C. callilepis var. callilepis (Fringebract Thistle) · C. canalense (Canal Thistle) · C. canescens (Platte Thistle) · C. canovirens (Gray Green Thistle) · C. canum (Queen Anne's Thistle) · C. carolinianum (Carolina Thistle) · C. chellyense (Queen Thistle) · C. chuskaense (Monarch Thistle) · C. ciliolatum (Ashland Thistle) · C. clavatum (Fish Lake Thistle) · C. clokeyi (Charleston Mountain Thistle) · C. congdonii (Rosette Thistle) · C. crassicaule (Slough Thistle) · C. crassum (Thistle) · C. cymosum (Peregrine Thistle) · C. diacanthus (Ivory Thistle) · C. discolor (Field Thistle) · C. douglasii (Douglas Thistle) · C. douglasii var. breweri (Douglas' Thistle) · C. douglasii var. breweri (Petr.) Keil & C.Turner (Douglas' Thistle) · C. douglasii var. douglasii (Douglas' Thistle) · C. douglasii var. douglasii DC. (Douglas' Thistle) · C. drummondii (Drummond Thistle) · C. eatonii (Eaton Thistle) · C. eatonii var. eatonii (Eaton's Thistle) · C. edule (Edible Thistle) · C. engelmannii (Engelmann Thistle) · C. eriophorum (Woolly Thistle) · C. erosum (Glory Thistle) · C. flodmanii (Flodman Thistle) · C. foliosum (Drummond's Thistle) · C. fontinale (Fountain Thistle) · C. fontinale (Greene) Jeps. var. campylon (H.K.Sharsmith) Pilz ex Keil & C.Turner (Fountain Thistle) · C. fontinale var. campylon (Mt Hamilton Thistle) · C. fontinale var. fontinale (Fountain Thistle) · C. fontinale var. obispoense (Chorro Creek Bog Thistle) · C. gilense (Gila Thistle) · C. grahamii (Graham's Thistle) · C. griseum (Gray Thistle) · C. hallii (Hall's Thistle) · C. helenioides (Melancholy Thistle) · C. heterophyllum (Curly Head) · C. hillii (Hill's Thistle) · C. hookerianum (Hooker Thistle) · C. horridulum (Bristly Thistle) · C. horridulum Michx. var. vittatum (Small) R.W.Long (Yellow Thistle) · C. horridulum var. horridulum (Yellow Thistle) · C. horridulum var. vittatum (Yellow Thistle) · C. humboldtense (Humboldt County Thistle) · C. hydrophilum (Suisun Thistle) · C. hydrophilum var. hydrophilum (Suisun Thistle) · C. hydrophilum var. vaseyi (Vasey's Thistle) · C. inornatum (Cloudcroft Thistle) · C. iowense (Iowa Thistle) · C. japonicum (Japanese Thistle) · C. japonicum 'Pink Beauty' (Japanese Thistle) · C. kamtschaticum (Kamchatka Thistle) · C. laterifolium (Porcupine Thistle) · C. lecontei (Le Conte's Thistle) · C. loncholepis (La Graciosa Thistle) · C. longistylum (Long-Styled Thistle) · C. mendocinum (Mendocino Thistle) · C. mexicanum (Mexican Thistle) · C. modestum (Lacy Thistle) · C. mohavense (Mohave Thistle) · C. murdockii (Murdock's Thistle) · C. muticum (Swamp Thistle) · C. navajoense (Navajo Thistle) · C. neomexicanum (Lavender Thistle) · C. neomexicanum var. neomexicanum (New Mexico Thistle) · C. neomexicanum var. utahense (Utah Thistle) · C. nuttallii (Nutalls Thistle) · C. occidentale (Cobweb Thistle) · C. occidentale (Nutt.) Jeps. var. californicum (Gray) Keil and C.Turner (California Thistle) · C. occidentale var. californicum (Cobwebby Thistle) · C. occidentale var. compactum (Compact Cobwebby Thistle) · C. occidentale var. occidentale (Cobwebby Thistle) · C. occidentale var. venustum (Cobwebby Thistle) · C. ochrocentrum (Yellow-Spine Thistle) · C. olivescens (Summer Thistle) · C. oreophilum (Crow Thistle) · C. osterhoutii (Osterhout's Thistle) · C. ownbeyi (Ownbey's Thistle) · C. pallidum (Pale Thistle)
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- A biological survey of the sand dune region on the south shore of Saginaw Bay, Michigan. Prepared under the direction of Alexander G. Ruthven. Lansing, Mich.: Wynkoop, Hallenbeck, Crawford co., state printers, 1911. url p. 119.
- A botanical exploration of the north shore of the gulf of St. Lawrence including an annotated list of the species of vascular plants, Ottawa, F. A. Acland, printer, 1922. url p. 112.
- A catalogue of the plants found in New Bedford and its vicinity: arranged according to the season of their flowering / by E.W. Hervey. New Bedford, Mass.: Press of E. Anthony, 1860. url p. 25.
- A dictionary of American plant names / compiled by Willard N. Clute. Joliet, Ill.: W.N. Clute, 1923. url p. 80.
- A flora of the state of New-York: comprising full descriptions of all the indigenous and naturalized plants hitherto discovered in the state: with remarks on their economical and medicinal properties / by John Torrey. Albany: Carroll and Cook, printers to the Assembly, 1843. url p. 406.
- A provisional list of the parasitic fungi of Wisconsin. Madison, 1914 url p. 878, p. 933.
- An ecological characterization of Coastal Maine (north and east of Cape Elizabeth) / Stewart I. Fefer and Patricia S. Schettig: principal investigators. Newton Corner, Mass.: Department of the Interior, U.S. Fish and Wildlife Service, Northeast Region, 1980. url .
- 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 102nd meridian / by Nathaniel Lord Britton and Hon. Addison Brown. New York: Scribner, 1913. url p. 553.
- An illustrated guide to the flowering plants of the middle Atlantic and New England states (excepting the grasses and sedges) the descriptive text written in familiar language, by George T. Stevens. .. with more than 1800 illustrations from drawings by the author. New York, Dodd, Mead and company, 1910. url p. 700.
- 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. 744.
- Annual report / Albany: University of the State of New York, 1902-1918. url p. 72.
- Annual report of the Michigan Academy of Science. Lansing, Mich.: The Academy, 1916-1921. url p. 271.
- Annual report of the New Jersey State Museum. Trenton, N.J.: MacCrellish & Quigley, url p. 779.
- Annual report of the Regents of the University on the condition of the State Cabinet of Natural History, with catalogues of the same. Albany, N.Y.: The University, 1848-1873. url p. 37.
- Annual report of the Secretary of the Board of Agriculture. Boston, Mass.: The Board, 1854-1915. url p. 7.
- Aquatic and wetland plants of southwestern United States, by Donovan S. Correll and Helen B. Correll. [Washington]Environmental Protection Agency; [For sale by the Supt. of Docs., U.S. Govt. Print. Off.]1972. url p. 1695.
- Bartonia;proceedings of the Philadelphia botanical club. .. 29 - 41 1957 - 19 Philadelphia, Philadelphia Botanical Club, Academy of Natural Sciences. url p. 11, p. 47, p. 48.
- Botany of the northern and middle states, or, A description of the plants found in the United States, north of Virginia: arranged according to the natural system: with a synopsis of the genera according to the Linnaean system. .. / Albany: Printed by Webster and Skinners. .., 1833. url p. 172.
- Britton, N. L. (ed.). North American flora. [New York]New York Botanical Garden. url p. 801, p. 871, p. 880.
- Brooklyn Botanic Garden record. 23 1934 [Brooklyn]: Brooklyn Botanic Garden, 1912-44. url p. 3.
- Budd's flora of the Canadian Prairie Provinces / [Ottawa]: Research Branch, Agriculture Canada, 1987. url p. 745.
- Bulletin / Ohio Biological Survey. Columbus, Ohio: Ohio State University, 1913- url p. 235.
- Bulletin of the Illinois State Laboratory of Natural History. Bloomington, Ill.: The Laboratory, 1876-1918. url p. 339, p. 368, p. 368.
- Bulletin of the United States Geological and Geographical Survey of the Territories / Department of the Interior. Washington: Government Printing Office, 1874- url p. 816.
- Catalog of Ohio vascular plants, arranged according to the phyletic classification; with notes on the geographical distribution in the state, based mainly on specimens in the State Herbarium, Botanical Laboratory, the Ohio State Univ Columbus, The Ohio State University, 1914. url .
- Catalogue of Canadian plants. .. Montreal [etc.]1883-1902. url p. 270.
- 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. 406.
- Checklist of plants of the Ottawa District. Ottawa, 1958. url p. 87.
- Compositae newsletter. Columbus, Ohio: Dept. of Botany, Ohio State University, 1975- url p. 26.
- Contributions from the Botanical Laboratory. Philadelphia: University of Pennsylvania Press, 1892- url .
- Contributions from the Osborn Botanical Laboratory. [New Haven?]Osborn Botanical Laboratory, Yale University, url p. 367.
- Contributions from the United States National Herbarium 21 1919 Washington, D.C.: Smithsonian Institution Press, 1890- url p. 292.
- Contributions from the University of Michigan Herbarium. 23 2001 Ann Arbor: University Herbarium, University of Michigan, 1939- url p. 349.
- Elliott, S. A sketch of the botany of South Carolina and Georgia /by Stephen Elliott. Charleston, S.C.: J.R. Schenck, 1821-24. url p. 269.
- Entomological news. [Philadelphia]American Entomological Society, 1925- url p. 138, p. 139.
- Field Museum of Natural History bulletin. Chicago, Field Museum of Natural History, -c1990. url p. 13, p. 15.
- Field book of American wild flowers; being a short description of their character and habits, a concise definition of their colors, and incidental references to the insects which assist in their fertilization, by F. Schuyler Mathews. 1912 New York, Putnam,  url p. 574.
- Field book of american wild flowers; being a short description of their character and habits, a concise definition of their colors, and incidental references to the insects which assist in their fertilization, by F. Schuyler Mathews... with numerous reproductions of water colors and pen-and-ink studies from nature by the author. New York, G.P. Putnam, 1902. url p. 540.
- Field, forest, and garden botany, a simple introduction to the common plants of the United States east of the Mississippi, both wild and cultivated. New York, Ivison, Phinney, Blakeman, 1869. url p. 186.
- First biennial report of the progress of the Geological survey of Michigan, embracing observations on the geology, zoo?logy and botany of the lower peninsula. Made to the governor, December 31, 1860. Lansing, Hosmer & Kerr, printers to the state, 1861. url .
- Flora Americae Septentrionalis: or, A systematic arrangement and description of the plants of North America. Containing, besides what have been described by preceding authors, many new and rare species, collected during twelve years by Frederick Pursh. .. London: Printed for James Black and son, 1816. url p. 506.
- Flora boreali-Americana, or, The botany of the northern parts of British America compiled principally from the plants collected by Dr. Richardson & Mr. Drummond on the late northern expeditions, under command of Captain Sir John Franklin, R.N. to which are added (by permission of by Sir William Jackson Hooker. London: H.G. Bohn, 1840. url .
- Flora of Berkshire County, Massachusetts. Boston, Printed for the Society, 1922. url , , p. 188, p. 340.
- Flora of Delaware and the Eastern Shore: an annotated list of the ferns and flowering plants of the peninsula of Delaware, Maryland and Virginia. [Wilmington]: Society of Natural History of Delaware, 1946. url p. 278.
- Flora of Indiana, by Charles C. Deam. Indianapolis, Wm. B. Burford printing co., contractor for state printing and binding, 1940. url p. 1002.
- Flora of Lancaster County: being descriptions of the seed-plants growing naturally in Lancaster County, Pennsylvania / by John Kunkel Small and Joel Jackson Carter. New York: The authors, 1913. url p. 311.
- Flora of Lancaster County; being descriptions of the seed- plants growing naturally in Lancaster County, Pennsylvanial. By John Kunkel Small and Joel Jackson Carter. New York, 1913. url p. 311.
- Flora of Middlesex County, Massachusetts, Malden, Middlesex Institute, 1888. url .
- Flora of Willoughby, Vermont / George G. Kennedy. Boston: [s.n.], 1904. url p. 133.
- 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. 292.
- 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. 387, p. 397.
- Flora of the Miami Valley, Ohio /c by A.P. Morgan. Dayton, Ohio: Literary Union, 1878. url p. 27.
- Flora of the vicinity of New York; a contribution to plant geography. [New York]1915 url p. 23.
- Florula Bostoniensis. A collection of plants of Boston and its vicinity, with their generic and specific characters, principal synonyms, descriptions, places of growth, and time of flowering, and occasional remarks. Boston, C. C. Little and J. Brown, 1840. url p. 310.
- Florula bostoniensis. A collection of plants of Boston and its vicinity, with their generic and specific characters, principal synonyms, descriptions, places of growth, and time of flowering, and occasional remarks. Boston, C. C. Little and J. Brown, 1840. url p. 310.
- Florula cestrica: an essay towards a catalogue of the phænogamous plants, native and naturalized, growing in the vicinity of the borough of West-Chester, in Chester County, Pennsylvania; to which is subjoined an appen by William Darlington. West-Chester, Penn.: Printed for the author by S. Siegfried, 1826. url p. 85.
- Gray's school and field book of botany. Consisting of "Lessons in botany" and "Field, forest, and garden botany" bound in one volume. By Asa Gray. New York, Ivison, Blakeman, Taylor, & company, 1881. url p. 186.
- Handbook of plants. New York: P. Henderson, 1881. url p. 47.
- Harper's guide to wild flowers, by Mrs. Caroline A. Creevey. New York, Harper, 1912. url p. 465.
- Hooker, W. J. Flora boreali-americana, or, the botany of the northern parts of British America: compiled principally from the plants collected by Dr. Richardson & Mr. Drummond on the late northern expeditions, under command of Captain Sir John Franklin, R.N. To which are added (by permission of the Horticultural society of London, ) those of Mr. Douglas, from north-west America, and of other naturalists /by Sir William Jackson Hooker. 2 1840 London, H.G. Bohn -1840. url p. 285, p. 334.
- Illinois River Bluffs area assessment / Illinois Department of Natural Resources, Office of Scientific Research and Analysis, [and the] State Geological Survey Division. Springfield, Ill.: Illinois Dept. of Natural Resources, 1998- url p. 171, p. 178.
- International catalogue of scientific literature. London: Published for the International Council by the Royal Society of London, 1902-1919. url p. 109, p. 535.
- Iowa parks. Conservation of Iowa historic, scenic and scientific areas. Also, a description of numerous areas suitable for public state parks, with reasons for their preservation. Report of the State board of con Pub. by the state of Iowa. Des Moines url p. 171.
- Iowa parks. Des Moines url p. 171.
- Journal of the New York Botanical Garden. 27 1926 Lancaster, Pa.: Published for the Garden by the New Era Printing Co., 1900- url p. 291.
- Lake Maxinkuckee. A physical and biological survey by Barton Warren Evermann and Howard Walton Clark. [Indianapolis]Dept. of Conservation, State of Indiana [Wm. B. Burford, printer]1920. url p. 447.
- Lake Maxinkuckee. a physical and biological survey by Barton Warren Evermann and Howard Walton Clark. [Indianapolis, Wm. B. Burford, printer]1920. url p. 447.
- Lake Maxinkuckee: a physical and biological survey / by Barton Warren Evermann and Howard Walton Clark. Indianapolis: Dept. of Conservation, 1920. url p. 447.
- Life histories of North American birds, from the parrots to the grackles, with special reference to their breeding habits and eggs, Washington, Smithsonian Institution, 1895. url .
- 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. 344.
- Manual of the southeastern flora: being descriptions of the seed plants growing naturally in Florida, Alabama, Mississippi, eastern Louisiana, Tennessee, North Carolina, South Carolina and Georgia. 1933 New York: The author, 1933. url p. 1481.
- Miramichi wild flowers by R. Mackenzie. Montreal: J. Lovell, 1887. url .
- 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. 122, p. 164, p. 221, p. 73.
- Miscellaneous publications / University of Michigan, Museum of Zoology. Ann Arbor, Mich.: The University, 1916- url p. 43.
- Museum bulletin / Albany, N.Y.: University of the State of New York, 1908-1916. url p. 72.
- New York State Museum bulletin. Albany, N.Y.: University of the State of New York, 1916-1944. url p. 110, p. 21.
- 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 .
- Phytologia memoirs. Plainfield, N.J.: H.N. Moldenke and A.L. Moldenke, 1980- url p. 567.
- Phytologia. Bronx Park, New York, H.A. Gleason and H.N. Moldenke, url p. 212, p. 247, p. 68.
- Plants of Rhode Island: being an enumeration of plants growing without cultivation in the State of Rhode Island / by James L. Bennett. Providence: Providence Press, 1888. url p. 23.
- Proceedings of the Academy of Natural Sciences of Philadelphia. Philadelphia, Academy of Natural Sciences of Philadelphia url p. 546, p. 546, p. 578.
- Proceedings of the Biological Society of Washington. Washington, Biological Society of Washington url p. 46.
- Proceedings of the Boston Society of Natural History. Boston [etc.]Boston Society of Natural History. url p. 149.
- Proceedings of the Entomological Society of Washington. Washington, etc.: Entomological Society of Washington url p. 243.
- Proceedings of the Indiana Academy of Science. Indianapolis, Ind.[s.n.] url p. 159, p. 374, p. 374.
- Report of the Botanist. Albany, N.Y.: University of the State of New York, Office of the Regents, 1871-1888 url p. 37.
- Report of the State Botanist. Albany, N.Y.: University of the State of New York, 1898-1925. url , , , p. 72.
- Report of the flora of Westchester County. Prepared for Bolton's History of the County. New YorkRoper & Burdge, 1880? url p. 795.
- Rock River area assessment / Illinois Department of Natural Resources, Office of Scientific Research and Analysis, Natural History Survey Division, in conjunction with State Geological Survey Division. Springfield, IL: Illinois Dept. of Natural Resources, 1996- url p. 125, p. 88.
- Science. New York, N.Y.: [s.n.]1880- url p. 333.
- South Carolina. Resources and population. Institutions and industries. Pub. by the State Board of Agriculture of South Carolina. Charleston, S.C.Walker, Evans & Cogswell, printers, 1883. url p. 328, p. 328.
- Studies in natural history. Iowa City, Ia. url p. 28.
- Syllogeus. Ottawa, National Museum of Natural Sciences, 1972-1995. url , p. 13, p. 39, p. 43, p. 54, p. 63, p. 68.
- The American midland naturalist. Notre Dame, Ind., University of Notre Dame. url p. 302, p. 70.
- The Canadian field-naturalist. 46 1932 Ottawa, Ottawa Field-Naturalists' Club. url [fig. 1] , p. 117, p. 218, p. 227, p. 253, p. 343, p. 655, p. 74, p. 91, p. 98.
- The Canadian journal of science, literature and history. Toronto: Canadian Institute, 1868-1878. url p. 295.
- The Canadian journal; a repertory of industry, science, and art; and a record of the proceedings of the Canadian Institute. Toronto: Published by H. Scobie for the Council of the Canadian Institute. url p. 223.
- The Canadian naturalist and geologist. Montreal: B. Dawson, 1856-1868. url p. 108.
- The Canadian record of science. Montreal, Natural History Society. url p. 221, p. 59.
- The Cottage gardeners' dictionary: describing the plants, fruits, and vegetables desirable for the garden, and explaining the terms and operations employed in their cultivation; with an alphabetical list of synonymes / edited by George W. Johnson. London: Henry G. Bohn, 1863. url p. 833.
- The Journal of the Iowa Academy of Science: JIAS. Cedar Falls, Iowa: The Academy, 1988- url p. 227.
- The Metaspermae of the Minnesota Valley: a list of the higher seed-producing plants indigenous to the drainage-basin of the Minnesota River / by Conway MacMillan. Minneapolis: Geological and Natural History Survey of Minnesota, 1892. url p. 558.
- The Metaspermae of the Minnesota valley; a list of the higher seed-producing plants indigenous to the drainage-basin of the Minnesota river. Minneapolis[Harrison & Smith, State Printers]1892 url p. 558.
- The North American Pyrenomycetes. A contribution to mycologic botany, Newfield, N. J., Ellis & Everhart, 1892 [c1890] url .
- The Ottawa naturalist. Ottawa, Ottawa Field-Naturalists' Club. url p. 157, p. 46.
- The Plant world. Baltimore [etc.]Plant World Association [etc.] url p. 106.
- The commonly occurring wild plants of Canada: a flora for the use of beginners. Toronto, Gage url p. 109.
- The elements of structural botany with special reference to the study of Canadian plants. .. Toronto, W. J. Gage & Co.[1897?] url .
- The flora of Essex County, Massachusetts. Salem, Essex Institute, 1880. url .
- The flora of the town of Southold, Long Island, and Gardiner's Island / New York: Torrey Botanical Club, 1914? url p. 253, p. 32.
- The geology of New Hampshire A report comprising the results of explorations ordered by the legislature. C. H. Hitchcock, state geologist Concord, E. A. Jenks, state printer, 1874-1878 url p. 402, p. 402.
- The geology of New Hampshire. A report comprising the results of explorations ordered by the legislature. Concord, E.A. Jenks, state printer, 1874-78. url .
- The plants of Michigan; simple keys for the identification of the native seed plants of the state, by Henry Allan Gleason. Ann Arbor, G. Wahr, c1918. url p. 118.
- The plants of Prince Edward Island / Ottawa: Research Branch, Agriculture Canada, 1985. url p. 260.
- The plants of Southern New Jersey with especial reference to the flora of the pine barrens and the geographic distribution of the species. Trenton, N. J., 1911. url .
- The plants of Southern New Jersey; with especial reference to the flora of the Pine Barrens and the geographic distribution of the species. Trenton, 1911. url p. 779.
- The plants of southern New Jersey; with especial reference to the flora of the pine barrens and the geographic distribution of the species. Trenton, 1911. url p. 779.
- The principles and practice of land drainage: embracing a brief history of underdraining; a detailed examination of its operation and advantages: a description of various kinds of drains, with practical directions for their construction: the manu By John H. Klippart. Cincinnati, R. Clarke & co., 1862. url p. 184.
- The standard cyclopedia of horticulture; a discussion, for the amateur, and the professional and commercial grower, of the kinds, characteristics and methods of cultivation of the species of plants grown in the regions of the United States a Illustrated with colored plates, four thousand engravings in the text, and ninety-six full-page cuts. New York, Macmillan, 1919 [c1914] url p. 775.
- Torreya. Burlington, Vt., Torrey Botanical Club, 1901-1945. url p. 32, p. 92.
- Transactions of the Connecticut Academy of Arts and Sciences. New Haven: Published by the Academy, 1866- url p. 367, p. 367.
- Transactions. Columbus, Ohio [etc.] url p. 247.
- Tulane studies in zoology and botany. 21 1979 New Orleans: Tulane University, [1968- url p. 40.
- Wild flowers of New York, by Homer D. House. Albany, The University of the state of New York, 1918. url , p. 323, p. 340, p. 345, p. 345.
- Wild flowers; New York, Macmillan Co., 1934. url , , .
- Hsi, Y.-T. 1960. Taxonomy, Distribution and Relationships of the Species of Cirsium Belonging to the Series Undulata. Ph.D. dissertation. University of Minnesota.
- Kelch, D. G. and B. G. Baldwin. 2003. Phylogeny and ecological radiation of New World thistles (Cirsium, Cardueae-Compositae) based on ITS and ETS rDNA sequence data. Molec. Ecol. 12: 141-151.
- Moore, R. J. and C. Frankton. 1969. Cytotaxonomy of some Cirsium species of the eastern United States, with a key to eastern species. Canad. J. Bot. 47: 1257-1275.
- Petrak, F. 1917. Die nordamerikanischen Arten der Gattung Cirsium. Beih. Bot. Centralbl. 35(2): 223-567.
- Brands, S.J. (comp.) 1989-present. The Taxonomicon. Universal Taxonomic Services, Zwaag, The Netherlands. Accessed January 10, 2012.
Accessed through GBIF Data Portal November 24, 2007:
- Missouri Botanical Garden, Missouri Botanical Garden
- US National Plant Germplasm System, United States National Plant Germplasm System Collection
- USDA PLANTS, USDA PLANTS Database
- Biodiversity Heritage Library NamebankID: 2657836
- Catalogue of Life Accepted Name Code: Ast-21320
- Global Biodiversity Information Facility Taxonkey: 13748960
- Globally Unique Identifier: urn:lsid:ipni.org:names:195721-1
- GRIN Nomen Number: 449809
- Integrated Taxonomic Information System (ITIS) Taxonomic Serial Number (TSN): 36387
- Natural Heritage Network Species Identifier: PDAST2E1U0
- U.S.D.A. Plant Symbol: CIMUS
- Zipcode Zoo Species Identifier: 27891
- David J. Keil "Cirsium". in Flora of North America Vol. 19, 20 and 21 Page 57, 66, 82, 83, 93, 95, 96, 97, 100, 102, 1. Oxford University Press. Online at EFloras.org. [back]
- "Cirsium muticum". in Flora of North America Vol. 19, 20 and 21 Page 98, 99, 112, 113, 120. Oxford University Press. Online at EFloras.org. ... [back]
- Mean = 291.740 meters (957.152 feet), Standard Deviation = 170.400 based on 486 observations. Altitude information for each observation from British Oceanographic Data Centre. [back]