Cirsium

Cirsium is a genus of perennial and biennial flowering plants in the Asteraceae, one of several genera known commonly as thistles. They are more precisely known as plume thistlesTemplate:Citation needed. These differ from other thistle genera (Carduus, Silybum and Onopordum) in having a seed with a pappus of feathered hairs on their achenes. The other genera have a pappus of simple unbranched hairs.<ref name="The Wild Flower Key">Template:Cite book</ref>

They are mostly native to Eurasia and northern Africa, with about 60<ref name="fna">{{#invoke:citation/CS1|citation |CitationClass=web }}</ref> species from North America (although several species have been introduced outside their native ranges). The lectotype species of the genus is Cirsium heterophyllum (L.) Hill.<ref>International Plant Names Index: Cirsium</ref>

Cirsium thistles are known for their effusive flower heads, usually purple, rose or pink, also yellow or white. The radially symmetrical disc flowers are at the end of the branches and are visited by many kinds of insects, featuring a generalised pollination syndrome.<ref>Template:Cite journal</ref> They have erect stems, with a characteristic enlarged base of the flower which is often spiny. The leaves are alternate, spiny in many (but not all) species, and in some species can be slightly to densely hairy. Extensions from the leaf base down the stem, called wings, can be lacking (Cirsium arvense), conspicuous (Cirsium vulgare), or inconspicuous. They can spread by seed, and also by rhizomes below the surface (Cirsium arvense). The seeds have a tuft of hair, or pappus, which can carry them far by wind.

Cirsium thistles are used as food plants by the larvae of some Lepidoptera species—see list of Lepidoptera that feed on Cirsium. The seeds are attractive to small finches such as American goldfinch.

Many species are considered weeds, typically by agricultural interests. Cirsium vulgare (spear thistle) is listed in the United States (where as a non-native invasive species it has been renamed "bull thistle") as a noxious weed in nine states.<ref name='USDA Plant Database'>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref> Some species in particular are cultivated in gardens and wildflower plantings for their aesthetic value and/or to support pollinators such as bees and butterflies. Some species dubbed weeds by various interest groups can also provide these benefits. Cirsium vulgare, for instance, ranked in the top 10 for nectar production in a UK plants survey conducted by the AgriLand project which is supported by the UK Insect Pollinators Initiative. Cirsium vulgare was also a top producer of nectar sugar in another study in Britain, ranked third with a production per floral unit of (2323 ± 418μg).<ref>Template:Cite journal</ref> Not only does it provide abundant nectar, it provides seeds for birds, such as the European goldfinch Carduelis carduelis, and supports the larvae of the Painted Lady butterfly Vanessa cardui.<ref name=Pollinators>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref> Some other common species are Cirsium arvense, Cirsium palustre, Cirsium oleraceum.

Some ecological organizations, such as the Xerces Society, have attempted to raise awareness of the benefits of thistles, to counteract the general agricultural and home garden labeling of thistles as unwanted weeds. The monarch butterfly (Danaus plexippus), for instance, was highlighted as relying upon thistles such as tall thistle (Cirsium altissimum) as nectar sources during its migration.<ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref> Some prairie and wildflower seed production companies in the United States supply bulk seed of native North American thistle species for wildlife habitat restoration, although availability tends to be low. Thistles are particularly valued by bumblebees for their high nectar production.

Certain species of Cirsium, like Cirsium monspessulanum, Cirsium pyrenaicum and Cirsium vulgare, have been traditionally used as food in rural areas of southern Europe. Cirsium oleraceum is cultivated as a food source in Japan and India. Cirsium setidens is used as a vegetable in Korean cuisine.

'Cirsium' is the Greek word for thistle, kirsos, likely derived from 'swollen vein'. The flower blooms April to August.

Selected species

{{#invoke:Labelled list hatnote|labelledList|Main article|Main articles|Main page|Main pages}} 383 species are accepted.<ref name = powo/> Selected species include: Template:Div col

• Cirsium acaule – dwarf thistle
• Cirsium altissimum Template:Small – roadside thistle, tall thistle
• Cirsium andersonii Template:Small – Anderson's thistle, rose thistle
• Cirsium andrewsii Template:Small – Franciscan thistle
• Cirsium arisanense Template:Small
• Cirsium arizonicum Template:Small – Arizona thistle
• Cirsium arvense Template:Small – creeping thistle, field thistle
  • Cirsium arvense var.argenteum
  • Cirsium arvense var. integrifolium
  • Cirsium arvense var. mite
  • Cirsium arvense var. vestitum
• Cirsium barnebyi Template:Small – Barneby's thistle
• Cirsium boninense Template:Small
• Cirsium brachycephalum Template:Small
• Cirsium brevifolium Template:Small – Palouse thistle
• Cirsium brevistylum Template:Small – clustered thistle
• Cirsium calcareum Template:Small – Cainville thistle
• Cirsium canescens Template:Small – Platte thistle, prairie thistle
• Cirsium canum Template:Small – Queen Anne's thistle
• Cirsium carolinianum Template:Small – Carolina thistle, soft thistle
• Cirsium centaureae Template:Small
• Cirsium chellyense Template:Small – queen thistle
• Cirsium ciliolatum Template:Small – ashland thistle
• Cirsium clavatum Template:Small – lake thistle
• Cirsium clokeyi Template:Small – Charleston Mountain thistle, whitespine thistle
• Cirsium congdonii Template:Small – rosette thistle
• Cirsium crassicaule Template:Small – slough thistle
• Cirsium creticum Template:Small
• Cirsium cymosum Template:Small – peregrine thistle
• Cirsium discolor Template:Small – field thistle, pasture thistle
• Cirsium dissectum Template:Small – meadow thistle (syn. Cirsium lanceolatum Template:Small non Template:Small)
• Cirsium douglasii Template:Small
• Cirsium drummondii Template:Small – dwarf thistle
• Cirsium durangense Template:Small
• Cirsium eatonii Template:Small – Eaton's thistle
• Cirsium edule Template:Small – edible thistle
• Cirsium engelmannii Template:Small – Engelmann thistle, Engelmann's thistle
• Cirsium erisithales Template:Small – yellow melancholy thistle
• Cirsium esculentum Template:Small
• Cirsium flodmanii Template:Small – Flodman thistle, Flodman's thistle
• Cirsium foliosum Template:Small – Drummond's thistle, elk thistle, leafy thistle, meadow thistle
• Cirsium fontinale Template:Small – fountain thistle
• Cirsium funkiae Template:Small – funky thistle
• Cirsium grahamii Template:Small – Graham's thistle
• Cirsium griseum Template:Small – gray thistle
• Cirsium helenioides Template:Small
• Cirsium heterophyllum Template:Small – melancholy thistle
• Cirsium hookerianum Template:Small – white thistle
• Cirsium horridulum Template:Small – yellow thistle
• Cirsium hydrophilum Template:Small – Suisun thistle
• Cirsium hypoleucum Template:Small
• Cirsium jaliscoense Template:Small
• Cirsium japonicum Template:Small – Japanese thistle
• Cirsium kamtschaticum Template:Small – Kamchatka thistle
• Cirsium lecontei Template:Small – Le Conte's thistle
• Cirsium leo Template:Small
• Cirsium libanoticum Template:Small
• Cirsium loncholepis Template:Small – LaGraciosa thistle
• Cirsium longistylum Template:Small – longstyle thistle
• Cirsium maritimum Template:Small
• Cirsium mexicanum Template:Small – Mexican thistle
• Cirsium mohavense Template:Small – Mojave thistle
• Cirsium muticum Template:Small – swamp thistle
• Cirsium neomexicanum Template:Small – lavender thistle, New Mexico thistle, powderpuff thistle
• Cirsium nipponicum Template:Small
• Cirsium nuttallii Template:Small – Nuttall's thistle
• Cirsium occidentale Template:Small – cobweb thistle
• Cirsium ochrocentrum Template:Small – yellowspine thistle
• Cirsium oleraceum Template:Small – cabbage thistle
• Cirsium ownbeyi Template:Small – Ownbey's thistle
• Cirsium palustre Template:Small – marsh thistle
• Cirsium parryi Template:Small – Parry's thistle or Cloudcroft thistle
• Cirsium peckii Template:Small – Steens Mountain thistle
• Cirsium pendulum Template:Small
• Cirsium perplexans Template:Small – Rocky Mountain thistle
• Cirsium pitcheri Template:Small – Pitcher's thistle, sand dune thistle
• Cirsium praeteriens Template:Small – Palo Alto thistle, lost thistle
• Cirsium pulcherrimum Template:Small – Wyoming thistle
• Cirsium pumilum Template:Small – pasture thistle
  • Cirsium pumilum var. hillii Template:Small – Hill's thistle
  • Cirsium pumilum var. pumilum
• Cirsium pyrenaicum Template:Small
• Cirsium quercetorum Template:Small – Alameda County thistle
• Cirsium remotifolium Template:Small – fewleaf thistle
  • Cirsium remotifolium var. odontolepis Template:Small
  • Cirsium remotifolium var. remotifolium – fewleaf thistle
  • Cirsium remotifolium var. rivulare Template:Small
• Cirsium repandum Template:Small – sandhill thistle
• Cirsium rhaphilepis Template:Small
• Cirsium rhinoceros Template:Small – Korean prickly thistle<ref>Template:Cite book</ref>
• Cirsium rhothophilum Template:Small – surf thistle
• Cirsium rivulare Template:Small – brook thistle
• Cirsium rydbergii Template:Small – Rydberg's thistle
• Cirsium scapanolepis Template:Small – mountain slope thistle
• Cirsium scariosum Template:Small – meadow thistle
• Cirsium scopulorum Template:Small – mountain thistle
• Cirsium setidens Template:Small – gondre or Korean thistle
• Cirsium spinosissimum Template:Small
• Cirsium texanum Template:Small – Texas thistle
• Cirsium tioganum Template:Small – stemless thistle
• †Cirsium toyoshimae Template:Small
• Cirsium tuberosum Template:Small – tuberous thistle
• Cirsium turneri Template:Small – cliff thistle
• Cirsium undulatum Template:Small – gray thistle, wavy-leaf thistle, wavyleaf thistle
  • Cirsium undulatum var. tracyi – Tracy's thistle, wavyleaf thistle
  • Cirsium undulatum var. undulatum – wavyleaf thistle
• Cirsium vinaceum Template:Small – Sacramento Mountain thistle, Sacramento Mountains thistle
• Cirsium virginianum Template:Small – Virginia thistle
• Cirsium vulgare Template:Small – spear thistle, common thistle (syn. Cirsium lanceolatum Template:Small)
• Cirsium wheeleri Template:Small – Wheeler's thistle
• Cirsium wrightii Template:Small – Wright's thistle

Hybrids

• Cirsium × canalense – canal thistle
• Cirsium × crassum – thistle
• Cirsium × erosum – glory thistle
• Cirsium × iowense – Iowa thistle
• Cirsium × vancouverense – Vancouver thistle

Formerly placed here

• Afrocirsium buchwaldii Template:Small (as Cirsium buchwaldii Template:Small)
• Afrocirsium schimperi Template:Small (as Cirsium schimperi Template:Small)
• Afrocirsium straminispinum Template:Small (Cirsium straminispinum Template:Small)
• Epitrachys italica Template:Small (as Cirsium italicum Template:Small)
• Lophiolepis eriophora Template:Small (as Cirsium eriophorum Template:Small) – woolly thistle
• Nuriaea dender Template:Small (as Cirsium dender Template:Small)
• Nuriaea engleriana Template:Small (as Cirsium englerianum Template:Small)
• Picnomon acarna Template:Small (as Cirsium acarna Template:Small) – soldier thistle

Image gallery

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Further reading

• Template:Cite book Template:ISBN

• Template:Commons category-inline