''Onopordum'', or cottonthistle, is a genus of plants in 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 ...

within 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 ...

. They are native to southern

Europe Europe is a large peninsula conventionally considered a continent in its own right because of its great physical size and the weight of its history and traditions. Europe is also considered a subcontinent of Eurasia and it is located entirel ...

, northern

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, the Canary Islands, the

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, and southwest and central

Asia Asia (, ) is one of the world's most notable geographical regions, which is either considered a continent in its own right or a subcontinent of Eurasia, which shares the continental landmass of Afro-Eurasia with Africa. Asia covers an are ...

. They grow on disturbed land, roadsides, arable land and pastures. They are biennials (rarely short-lived

perennials A perennial plant or simply perennial is a plant that lives more than two years. The term ('' per-'' + '' -ennial'', "through the years") is often used to differentiate a plant from shorter-lived annuals and biennials. The term is also widel ...

) with branched, spinose winged stems, growing 0.5–3 m tall. In the first season they form a basal rosette of gray-green

felted A felted material is a hairy or filamentous (hairy-like) fibre that is densely packed or tangled, forming felt or felt-like structures. Anatomy and zoology The dermis is described in Gray's Anatomy as "felted connective tissue, with a varyi ...

leaves and rarely a few

flower A flower, sometimes known as a bloom or blossom, is the reproductive structure found in flowering plants (plants of the division Angiospermae). The biological function of a flower is to facilitate reproduction, usually by providing a mechani ...

heads. In the second season they grow rapidly to their final height, flowering extensively, and then die off after seed maturation.Flora of China Vol. 20-21 Page 159, 大翅蓟属 da chi ji shu ''Onopordum'' Linnaeus, Sp. Pl. 2: 827. 1753.
/ref> The leaves are dentate or shallowly lobed to compound with several pinnatifid or deeply cut leaflets, and strongly spiny. The terminal flower head is typical for thistles, a semi-spherical to ovoid

capitulum capitulum (plural capitula) may refer to: *the Latin word for chapter ** an index or list of chapters at the head of a gospel manuscript ** a short reading in the Liturgy of the Hours *** derived from which, it is the Latin for the assembly known ...

with purple (seldom white or pink) disc florets. There are no ray florets. The receptacle is glabrous with dentate margins. The tube of the corolla is slender, sac-shaped and symmetrical. The anthers have awl-shaped outgrowths on the top. The capitula have several overlapping rows of leathery basal simple linear-lanceolate spines. These are smooth to slightly pubescent. These plants propagate only by

seed A seed is an embryonic plant enclosed in a protective outer covering, along with a food reserve. The formation of the seed is a part of the process of reproduction in seed plants, the spermatophytes, including the gymnosperm and angiospe ...

. The seed heads mature in mid-summer, releasing their seeds. The

fruit In botany, a fruit is the seed-bearing structure in flowering plants that is formed from the ovary after flowering. Fruits are the means by which flowering plants (also known as angiosperms) disseminate their seeds. Edible fruits in particu ...

is a glabrous achene, 4–6 mm long and with 4-50 ribs. The pappus consists of many rows of simple, fine to minutely rough hairs, united in a circular base. ''Onopordum'' species are used as food plants by the

larva A larva (; plural larvae ) is a distinct juvenile form many animals undergo before metamorphosis into adults. Animals with indirect development such as insects, amphibians, or cnidarians typically have a larval phase of their life cycle. ...

e of some Lepidoptera species including '' Coleophora onopordiella'' (feeds exclusively on ''O. acanthium''). In the

Greek Greek may refer to: Greece Anything of, from, or related to Greece, a country in Southern Europe: *Greeks, an ethnic group. *Greek language, a branch of the Indo-European language family. **Proto-Greek language, the assumed last common ancestor ...

island of

Crete Crete ( el, Κρήτη, translit=, Modern: , Ancient: ) is the largest and most populous of the Greek islands, the 88th largest island in the world and the fifth largest island in the Mediterranean Sea, after Sicily, Sardinia, Cyprus, ...

a native species called agriagginara (αγριαγγινάρα) or koufoti (κουφωτοί) has its heads (flowers) and tender leaves eaten raw by the locals. ; Species * '' Onopordum acanthium'' L. - Cotton thistle, Scotch thistle, Scotch common-thistle, heraldic thistle, woolly thistle - widespread across Europe and temperate Asia * ''

Onopordum acaulon ''Onopordum'', or cottonthistle, is a genus of plants in the tribe Cardueae within the family Asteraceae. They are native to southern Europe, northern Africa, the Canary Islands, the Caucasus, and southwest and central Asia. They grow on disturb ...

'' L. - Stemless thistle, horse thistle - France, Spain, Algeria, Morocco, Tunisia * ''

Onopordum alexandrinum ''Onopordum'', or cottonthistle, is a genus of plants in the tribe Cardueae within the family Asteraceae. They are native to southern Europe, northern Africa, the Canary Islands, the Caucasus, and southwest and central Asia. They grow on disturb ...

'' Boiss. - Egypt, Palestine, Lebanon, Syria, Israel, Jordan * '' Onopordum algeriense'' (Munby) Pomel - Algeria * '' Onopordum ambiguum'' Fresen. - Egypt, Palestine, Lebanon, Syria, Israel, Jordan * '' Onopordum anatolicum'' (Boiss.) Eig. - Turkey * '' Onopordum arenarium'' M.Hossain & M.A.A.Al-Sarraf - Algeria, Morocco, Tunisia, Libya * '' Onopordum armenum'' Grossh. - Caucasus, Iran, Turkey * '' Onopordum blancheanum'' (Eig) Danin - Israel, Palestine, Jordan, Syria, Lebanon * '' Onopordum boissierianum'' Raab-Straube & Greuter - Turkey * '' Onopordum bracteatum'' Boiss. & Heldr. - Greece, Turkey, Cyprus * '' Onopordum canum'' Eig - Iran, Jordan, Israel, Turkey * '' Onopordum carduchorum'' Bornm. & Beauverd - Lebanon, Syria, Turkey, Iran * '' Onopordum carduelium'' Bolle - Canary Islands * '' Onopordum carduiforme'' Boiss. - Egypt, Palestine, Lebanon, Syria, Israel, Jordan * '' Onopordum carmanicum'' (Bornm.) Bornm. - Iran * '' Onopordum caulescens'' d'Urv. - Greece * '' Onopordum cinereum'' Grossh. - Caucasus, Turkey, Iran, Turkmenistan, Afghanistan * '' Onopordum corymbosum'' Willk. - France, Spain * '' Onopordum cynarocephalum'' Boiss. & Blanche - Palestine, Lebanon, Syria, Israel, Jordan * ''

Onopordum cyrenaicum ''Onopordum'', or cottonthistle, is a genus of plants in the tribe Cardueae within the family Asteraceae. They are native to southern Europe, northern Africa, the Canary Islands, the Caucasus, and southwest and central Asia. They grow on disturb ...

'' Maire & Weiller - Libya * '' Onopordum dissectum'' Murb. - Spain, Morocco * '' Onopordum dyris'' Maire - Morocco * '' Onopordum elongatum'' Lam. * '' Onopordum eriocephalum'' Rouy - France * '' Onopordum espinae'' Coss. * '' Onopordum heteracanthum'' C.A.Mey. - Caucasus, Lebanon, Turkey, Syria, Palestine, Iran, Afghanistan, Saudi Arabia * '' Onopordum horridum'' Viv. - Italy * ''

Onopordum illyricum ''Onopordum illyricum'' is a species of thistle known by the common name Illyrian thistle, or Illyrian cottonthistle. It is native to southwestern Europe, but has been introduced into Australia and California, where it has become a noxious weed. ...

'' L. - Illyrian thistle, Illyrian cottonthistle - Mediterranean * '' Onopordum leptolepis'' DC. - from Palestine to Altay + Xinjiang * '' Onopordum macracanthum''

Schousb Peter Schousboe (1766–1832) was a Danish botanist. Biography Peder Kofod Anker Schousboe was born in Rønne, Denmark and died in Tangier, Morocco, having served as Danish consul general in Tangier from 1800 onwards. He conducted a botanic ...

. - Spain, Portugal, Italy, Morocco, Algeria * '' Onopordum macrocanthum'' d'Urv. * '' Onopordum macrocephalum'' Eig - Palestine, Lebanon, Syria, Israel, Jordan * '' Onopordum mesatlanticum'' Emb. & Maire - Morocco * '' Onopordum micropterum'' Pau - Spain, Canary Islands * '' Onopordum minor'' L. - Iran * '' Onopordum myriacanthum'' Boiss. - Greece, Turkey, Bulgaria * '' Onopordum nervosum'' Boiss. - Moor's cottonthistle - Spain, Portugal * '' Onopordum parnassicum'' Boiss. & Heldr. - Greece, Turkey * '' Onopordum platylepis'' (Coss. ex Murb.) Murb. - Libya, Tunisia * '' Onopordum polycephalum'' Boiss. - Turkey * '' Onopordum prjachinii'' Tamamsch. - Uzbekistan, Kyrgyzstan, Tajikistan * '' Onopordum seravschanicum'' Tamamsch. - Uzbekistan, Kyrgyzstan, Tajikistan * '' Onopordum sibthorpianum'' Boiss. & Heldr. - Greece, Sicily, Malta, Turkey, North Macedonia, Saudi Arabia * '' Onopordum tauricum'' Willd. - Turkish thistle, Taurian thistle, Taurus cottonthistle, bull cottonthistle - southern + central Europe, Ukraine, Middle East * '' Onopordum turcicum'' Danin - Turkey * '' Onopordum wallianum'' Maire - Morocco ; Natural hybrids * ''Onopordum'' × ''brevicaule'' (''Onopordum acaulon'' × ''Onopordum acanthium'' ) * ''Onopordum'' × ''erectum'' (''Onopordum nervosum'' ssp. ''castellanum'' × ''Onopordum tauricum'' ssp. ''corymbosum'' ) * ''Onopordum'' × ''macronervosum'' (''Onopordum nervosum'' × ''Onopordum macrocanthum'') * ''Onopordum'' × ''onubense'' (''Onopordum dissectum'' × ''Onopordum macrocanthum'') * ''Onopordum'' × ''spinosissimum'' (''Onopordum illyricum'' × ''Onopordum acanthium'')

Invasive problems

Some species of ''Onopordum'' have been introduced as

ornamental plant Ornamental plants or garden plants are plants that are primarily grown for their beauty but also for qualities such as scent or how they shape physical space. Many flowering plants and garden varieties tend to be specially bred cultivars that ...

s in the temperate regions of North America and Australia, where they have become naturalised in the wild. In most of these countries, these thistles are considered noxious

weed A weed is a plant considered undesirable in a particular situation, "a plant in the wrong place", or a plant growing where it is not wanted.Harlan, J. R., & deWet, J. M. (1965). Some thoughts about weeds. ''Economic botany'', ''19''(1), 16-24. ...

s, especially in Australia where a biological control program has been set up (using the Rosette Crown

Weevil Weevils are beetles belonging to the superfamily Curculionoidea, known for their elongated snouts. They are usually small, less than in length, and herbivorous. Approximately 97,000 species of weevils are known. They belong to several families, ...

, '' Trichosirocalus briesei''). In North America, there are also ''Trichosirocalus'' control programs, but they have proved detrimental to native thistles.

References

* Briese, D.T., Lane, D., Hyde-Wyatt, B.H., Crocker, J., Diver, R.G. (1990). Distribution of thistles of the genus ''Onopordum'' in Australia. Plant Protection Quarterly 5: 23-27. {{Taxonbar, from=Q28104 Asteraceae genera