flowering plant
Flowering plants are plants that bear flowers and fruits, and form the clade Angiospermae (), commonly called angiosperms. The term "angiosperm" is derived from the Greek words ('container, vessel') and ('seed'), and refers to those plants th ...
s in the family
Asteraceae
The family Asteraceae, alternatively Compositae, consists of over 32,000 known species of flowering plants in over 1,900 genera within the order Asterales. Commonly referred to as the aster, daisy, composite, or sunflower family, Compositae w ...
, and the tribe
Cardueae
The Cardueae are a tribe of flowering plants in the daisy family (Asteraceae) and the subfamily Carduoideae. Most of them are commonly known as thistles; four of the best known genera are '' Carduus'', '' Cynara'' (containing the widely eaten ar ...
, one of two genera considered to be true thistles, the other being '' Cirsium''. Plants of the genus are known commonly as plumeless thistles.''Carduus''. Integrated Taxonomic Information System (ITIS).''Carduus''. Flora of North America. They are native to Eurasia and Africa, and several are known elsewhere as
introduced species
An introduced species, alien species, exotic species, adventive species, immigrant species, foreign species, non-indigenous species, or non-native species is a species living outside its native distributional range, but which has arrived there ...
. This genus is noted for its disproportionately high number of
noxious weed
A noxious weed, harmful weed or injurious weed is a weed that has been designated by an agricultural or other governing authority as a plant that is injurious to agricultural or horticultural crops, natural habitats or ecosystems, or humans or liv ...
s compared to other flowering plant genera.
Etymology
The genus name ''Carduus'' is from the
Latin
Latin (, or , ) is a classical language belonging to the Italic branch of the Indo-European languages. Latin was originally a dialect spoken in the lower Tiber area (then known as Latium) around present-day Rome, but through the power of the ...
for "a kind of thistle"''Carduus''. The Jepson eFlora 2013. or "thistlelike plant". It is related to the word ''Cardonnacum'' ("a place of chardons or thistles"), which is the origin of
Chardonnay
Chardonnay (, , ) is a green-skinned grape variety used in the production of white wine. The variety originated in the Burgundy wine region of eastern French wine, France, but is now grown wherever wine is produced, from English wine, Englan ...
, the name of the
grape variety
This list of grape varieties includes cultivated grapes, whether used for wine, or eating as a table grape, fresh or dried (raisin, currant, sultana). For a complete list of all grape species including those unimportant to agriculture, see Viti ...
. It is also related to the word ''card'', which as a noun means a device (often a stiff-bristled brush) for aligning and cleaning fibers, and as a verb means the action of processing fibers in that way.
Description
These are usually annual or biennial herbs, sometimes perennial. Species often grow 2 meters in height but are known to reach 4 meters. The erect stems are winged and spiny, and usually have woolly hairs. The leaf blades are hairy to hairless and entire or divided into lobes, and they have spine-toothed edges. The
flower heads
A pseudanthium (Greek for "false flower"; ) is an inflorescence that resembles a flower. The word is sometimes used for other structures that are neither a true flower nor a true inflorescence. Examples of pseudanthia include flower heads, compos ...
are solitary or borne in
inflorescence
An inflorescence is a group or cluster of flowers arranged on a stem that is composed of a main branch or a complicated arrangement of branches. Morphologically, it is the modified part of the shoot of seed plants where flowers are formed o ...
s of up to 20. The head is spherical to cylindrical and covered in several layers of spreading or curving spine-tipped phyllaries. It contains long, tubular disc florets in shades of white, pink, or purple. The fruit is a cypsela tipped with a pappus of barbed bristles or scales.
Ecology
Several ''Carduus'' are notorious invasive plants outside their native range, for example, in
Australia
Australia, officially the Commonwealth of Australia, is a Sovereign state, sovereign country comprising the mainland of the Australia (continent), Australian continent, the island of Tasmania, and numerous List of islands of Australia, sma ...
and the
United States
The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 states, a federal district, five major unincorporated territorie ...
.Genus ''Carduus''. Encycloweedia. California Department of Food and Agriculture. Species such as ''C. acanthoides'', ''C. nutans'', ''C. pycnocephalus'', and ''C. tenuiflorus'' easily become weedy in disturbed habitat, such as
overgrazed
Overgrazing occurs when plants are exposed to intensive grazing for extended periods of time, or without sufficient recovery periods. It can be caused by either livestock in poorly managed agricultural applications, game reserves, or nature rese ...
pasture. ''C. nutans'' is
allelopathic
Allelopathy is a biological phenomenon by which an organism produces one or more biochemicals that influence the germination, growth, survival, and reproduction of other organisms. These biochemicals are known as allelochemicals and can have ben ...
, producing compounds that inhibit the growth and development of other plants.
Agents of
biological pest control
Biological control or biocontrol is a method of controlling pests, such as insects, mites, weeds, and plant diseases, using other organisms. It relies on predation, parasitism, herbivory, or other natural mechanisms, but typically also invo ...
fungus
A fungus ( : fungi or funguses) is any member of the group of eukaryotic organisms that includes microorganisms such as yeasts and molds, as well as the more familiar mushrooms. These organisms are classified as a kingdom, separately from th ...
, may also be used against ''C. nutans''.
Diversity
File:20130413Carduus acanthoides1.jpg, '' Carduus acanthoides''
File:Partially opened flower bud of Carduus nutans.jpg, ''
Carduus nutans
''Carduus nutans'', with the common names musk thistle, nodding thistle, and nodding plumeless thistle, is a biennial plant in the daisy and sunflower family Asteraceae. It is native to regions of Eurasia.
Description
''Carduus nutans'' is usual ...
Carduus keniensis
''Carduus'' is a genus of flowering plants in the family Asteraceae, and the tribe Cardueae, one of two genera considered to be true thistles, the other being ''Cirsium''. Plants of the genus are known commonly as plumeless thistles.
Carduus acicularis
''Carduus argentatus'', sometimes known as the silver thistle, is an annual herb in the family Asteraceae. As a member of the genus ''Carduus'' it is known as a plumeless thistle.Carduus adpressus''
*'' Carduus affinis''
*''
Carduus afromontanus
''Carduus'' is a genus of flowering plants in the family Asteraceae, and the tribe Cardueae, one of two genera considered to be true thistles, the other being ''Cirsium''. Plants of the genus are known commonly as plumeless thistles.
''
*''
Carduus amanus
''Carduus'' is a genus of flowering plants in the family Asteraceae, and the tribe Cardueae, one of two genera considered to be true thistles, the other being '' Cirsium''. Plants of the genus are known commonly as plumeless thistles.
Carduus argentatus
''Carduus argentatus'', sometimes known as the silver thistle, is an annual herb in the family Asteraceae. As a member of the genus ''Carduus'' it is known as a plumeless thistle.Carduus argyroa
''Carduus'' is a genus of flowering plants in the family Asteraceae, and the tribe Cardueae, one of two genera considered to be true thistles, the other being '' Cirsium''. Plants of the genus are known commonly as plumeless thistles.
''
*''
Carduus asturicus
''Carduus'' is a genus of flowering plants in the family Asteraceae, and the tribe Cardueae, one of two genera considered to be true thistles, the other being '' Cirsium''. Plants of the genus are known commonly as plumeless thistles.
Carduus axillaris
''Carduus'' is a genus of flowering plants in the family Asteraceae, and the tribe Cardueae, one of two genera considered to be true thistles, the other being '' Cirsium''. Plants of the genus are known commonly as plumeless thistles.
Carduus bourgeanus
''Carduus'' is a genus of flowering plants in the family Asteraceae, and the tribe Cardueae, one of two genera considered to be true thistles, the other being '' Cirsium''. Plants of the genus are known commonly as plumeless thistles.
Carduus carlinoides
''Carduus'' is a genus of flowering plants in the family Asteraceae, and the tribe Cardueae, one of two genera considered to be true thistles, the other being '' Cirsium''. Plants of the genus are known commonly as plumeless thistles.
Carduus chevallieri
''Carduus'' is a genus of flowering plants in the family Asteraceae, and the tribe Cardueae, one of two genera considered to be true thistles, the other being '' Cirsium''. Plants of the genus are known commonly as plumeless thistles.
Carduus clavulatus
''Carduus'' is a genus of flowering plants in the family Asteraceae, and the tribe Cardueae, one of two genera considered to be true thistles, the other being '' Cirsium''. Plants of the genus are known commonly as plumeless thistles.
Carduus fallax
''Carduus'' is a genus of flowering plants in the family Asteraceae, and the tribe Cardueae, one of two genera considered to be true thistles, the other being '' Cirsium''. Plants of the genus are known commonly as plumeless thistles.
Carduus getulus
''Carduus'' is a genus of flowering plants in the family Asteraceae, and the tribe Cardueae, one of two genera considered to be true thistles, the other being '' Cirsium''. Plants of the genus are known commonly as plumeless thistles.
Carduus ibicensis
''Carduus'' is a genus of flowering plants in the family Asteraceae, and the tribe Cardueae, one of two genera considered to be true thistles, the other being '' Cirsium''. Plants of the genus are known commonly as plumeless thistles.
''
*''
Carduus jordanii
''Carduus'' is a genus of flowering plants in the family Asteraceae, and the tribe Cardueae, one of two genera considered to be true thistles, the other being '' Cirsium''. Plants of the genus are known commonly as plumeless thistles.
''
*''
Carduus juratzkae
''Carduus'' is a genus of flowering plants in the family Asteraceae, and the tribe Cardueae, one of two genera considered to be true thistles, the other being '' Cirsium''. Plants of the genus are known commonly as plumeless thistles.
''
*''
Carduus keniensis
''Carduus'' is a genus of flowering plants in the family Asteraceae, and the tribe Cardueae, one of two genera considered to be true thistles, the other being ''Cirsium''. Plants of the genus are known commonly as plumeless thistles.
Carduus leptocladus
''Carduus'' is a genus of flowering plants in the family Asteraceae, and the tribe Cardueae, one of two genera considered to be true thistles, the other being '' Cirsium''. Plants of the genus are known commonly as plumeless thistles.
''
*''
Carduus litigiosus
''Carduus'' is a genus of flowering plants in the family Asteraceae, and the tribe Cardueae, one of two genera considered to be true thistles, the other being '' Cirsium''. Plants of the genus are known commonly as plumeless thistles.
''
*''
Carduus lobulatus
''Carduus'' is a genus of flowering plants in the family Asteraceae, and the tribe Cardueae, one of two genera considered to be true thistles, the other being '' Cirsium''. Plants of the genus are known commonly as plumeless thistles.
''
*''
Carduus lusitanicus
''Carduus'' is a genus of flowering plants in the family Asteraceae, and the tribe Cardueae, one of two genera considered to be true thistles, the other being '' Cirsium''. Plants of the genus are known commonly as plumeless thistles.
Carduus macrocephalus
''Carduus'' is a genus of flowering plants in the family Asteraceae, and the tribe Cardueae, one of two genera considered to be true thistles, the other being '' Cirsium''. Plants of the genus are known commonly as plumeless thistles.
''
*''
Carduus malyi
''Carduus'' is a genus of flowering plants in the family Asteraceae, and the tribe Cardueae, one of two genera considered to be true thistles, the other being '' Cirsium''. Plants of the genus are known commonly as plumeless thistles.
Carduus membranaceus
''Carduus'' is a genus of flowering plants in the family Asteraceae, and the tribe Cardueae, one of two genera considered to be true thistles, the other being '' Cirsium''. Plants of the genus are known commonly as plumeless thistles.
Carduus millefolius
''Carduus'' is a genus of flowering plants in the family Asteraceae, and the tribe Cardueae, one of two genera considered to be true thistles, the other being '' Cirsium''. Plants of the genus are known commonly as plumeless thistles.
Carduus myriacanthus
''Carduus'' is a genus of flowering plants in the family Asteraceae, and the tribe Cardueae, one of two genera considered to be true thistles, the other being ''Cirsium''. Plants of the genus are known commonly as plumeless thistles.
''
*''
Carduus nervosus
''Carduus'' is a genus of flowering plants in the family Asteraceae, and the tribe Cardueae, one of two genera considered to be true thistles, the other being '' Cirsium''. Plants of the genus are known commonly as plumeless thistles.
''
*''
Carduus nigrescens
''Carduus'' is a genus of flowering plants in the family Asteraceae, and the tribe Cardueae, one of two genera considered to be true thistles, the other being '' Cirsium''. Plants of the genus are known commonly as plumeless thistles.
''
*''
Carduus nutans
''Carduus nutans'', with the common names musk thistle, nodding thistle, and nodding plumeless thistle, is a biennial plant in the daisy and sunflower family Asteraceae. It is native to regions of Eurasia.
Description
''Carduus nutans'' is usual ...
Carduus ramosissimus
''Carduus'' is a genus of flowering plants in the family Asteraceae, and the tribe Cardueae, one of two genera considered to be true thistles, the other being '' Cirsium''. Plants of the genus are known commonly as plumeless thistles.
Carduus weizensis
''Carduus'' is a genus of flowering plants in the family Asteraceae, and the tribe Cardueae, one of two genera considered to be true thistles, the other being '' Cirsium''. Plants of the genus are known commonly as plumeless thistles.
Carduus × cyrneus
''Carduus'' is a genus of flowering plants in the family Asteraceae, and the tribe Cardueae, one of two genera considered to be true thistles, the other being '' Cirsium''. Plants of the genus are known commonly as plumeless thistles.