Cirsium

***Cirsium*** is a genus of flowering plants in the family Asteraceae.  It is one of many genera with the common name being **thistles**.  Other genera known as thistles include _Carduus_, _Cynara_, _Onopordon_, and _Silybum_.

They are mostly native to Eurasia and northern Africa.  There are about 60 species in North America (although many species have been naturalized outside their native ranges).

Most species are considered weeds.  _Cirsium vulgare_ is listed as a weed in nine US states.  Some species are planted in gardens for their beauty and to attract butterflies.

## Species

- _Cirsium acarna_ - Soldier Thistle
- _Cirsium acaule_ - Stemless Thistle, Dwarf Thistle
- _Cirsium altissimum_ - Roadside Thistle, Tall Thistle
- _Cirsium amblylepis_ - Mt. Tamalpais Thistle
- _Cirsium andersonii_ - Anderson's Thistle, Rose Thistle
- _Cirsium andrewsii_ - Franciscan Thistle
- _Cirsium araneans_ - Jeweled Thistle
- _Cirsium arcuum_ - Powderpuff Thistle
- _Cirsium aridum_ - Desert Thistle
- _Cirsium arizonicum_ - Arizona Thistle
- _Cirsium arvense_ - Creeping Thistle, Field Thistle, Canada Thistle
    - _Cirsium arvense_ var._argenteum_
    - _Cirsium arvense_ var. _integrifolium_
    - _Cirsium arvense_ var. _mite_
    - _Cirsium arvense_ var. _vestitum_
- _Cirsium barnebyi_ - Barneby's Thistle
- _Cirsium brachycephalum_
- _Cirsium brevifolium_ - Palouse Thistle
- _Cirsium brevistylum_ - Clustered Thistle
- _Cirsium calcareum_ - Cainville Thistle
- _Cirsium californicum_ - California Thistle
- _Cirsium callilepis_ - Fringebract Thistle
- _Cirsium campylon_ - Mount Hamilton Thistle
- _Cirsium canescens_ - Platte Thistle, Prairie Thistle
- _Cirsium canovirens_ - Graygreen Thistle
- _Cirsium canum_ - Queen Anne's Thistle
- _Cirsium carolinianum_ - Carolina Thistle, Soft Thistle
- _Cirsium caulescens_
- _Cirsium centaureae_
- _Cirsium chellyense_ - Queen Thistle
- _Cirsium chuskaense_ - Monarch Thistle
- _Cirsium ciliolatum_ - Ashland Thistle
- _Cirsium clavatum_ - Lake Thistle
- _Cirsium clokeyi_ - Charleston Mountain Thistle, Whitespine Thistle
- _Cirsium congdonii_ - Rosette Thistle
- _Cirsium costaricense_
- _Cirsium coulteri_ - Coulter’s Thistle
- _Cirsium crassicaule_ - Slough Thistle
- _Cirsium cymosum_ - Peregrine Thistle
- _Cirsium diacanthum_
- _Cirsium discolor_ - Field Thistle, Pasture Thistle
- _Cirsium dissectum_ - Meadow Thistle
- _Cirsium douglasii_
- _Cirsium drummondii_ - Dwarf Thistle
- _Cirsium durangense_
- _Cirsium eatonii_ - Eaton's Thistle
- _Cirsium edule_ - Edible Thistle
- _Cirsium engelmannii_ - Engelmann Thistle, Engelmann's Thistle
- _Cirsium eriophorum_ - Woolly Thistle
- _Cirsium erisithales_ - Yellow Melancholy Thistle
- _Cirsium esculentum_
- _Cirsium flodmanii_ - Flodman Thistle, Flodman's Thistle
- _Cirsium foliosum_ - Drummond's Thistle, Elk Thistle, Leafy Thistle, Meadow Thistle
- _Cirsium fontinale_ - Fountain Thistle
- _Cirsium gilense_ - Gila Thistle
- _Cirsium grahamii_ - Graham's Thistle
- _Cirsium griseum_ - Gray Thistle
- _Cirsium hallii_ - Hall's Thistle
- _Cirsium helenioides_ - Melancholy Thistle, Common Melancholy Thistle
- _Cirsium heterophyllum_ - Melancholy Thistle
- _Cirsium hillii_ - Hill's Thistle
- _Cirsium hookerianum_ - White Thistle
- _Cirsium horridulum_ - Yellow Thistle
- _Cirsium humboldtense_ - Humboldt County Thistle
- _Cirsium hydrophilum_ - Suisun Thistle
- _Cirsium hypoleucum_
- _Cirsium inornatum_ - Cloudcroft Thistle
- _Cirsium japonicum_ - Japanese Thistle
- _Cirsium kamtschaticum_ - Kamchatka Thistle
- _Cirsium lanatum_ - Hairy Thistle
- _Cirsium laterifolium_ - Porcupine Thistle
- _Cirsium lecontei_ - Le Conte's Thistle
- _Cirsium leo_
- _Cirsium libanoticum_
- _Cirsium loncholepis_ - LaGraciosa Thistle
- _Cirsium longistylum_ - Longstyle Thistle
- _Cirsium maritimum_
- _Cirsium mendocinum_ - Mendocino Thistle
- _Cirsium mexicanum_ - Mexican Thistle
- _Cirsium modestum_ - Lacy Thistle
- _Cirsium mohavense_ - Mojave Thistle
- _Cirsium murdockii_ - Murdock's Thistle
- _Cirsium muticum_ - Swamp Thistle
- _Cirsium navajoense_ - Navajo Thistle
- _Cirsium neomexicanum_ - Lavender Thistle, New Mexico Thistle
- _Cirsium nipponicum_
- _Cirsium nuttallii_ - Nuttall's Thistle
- _Cirsium occidentale_ -Cobweb Thistle
- _Cirsium ochrocentrum_ - Yellowspine Thistle
- _Cirsium oleraceum_ - Cabbage thistle
- _Cirsium olivescens_ - Summer Thistle
- _Cirsium oreophilum_ - Crow Thistle
- _Cirsium osterhoutii_ - Osterhout's Thistle
- _Cirsium ownbeyi_ - Ownbey's Thistle
- _Cirsium pallidum_ - Pale Thistle
- _Cirsium palustre_ - Marsh thistle, European Swamp Thistle
- _Cirsium parryi_ - Parry's Thistle
- _Cirsium pastoris_ - Snowy Thistle
- _Cirsium peckii_ - Steen Mountain Thistle
- _Cirsium pendulum_
- _Cirsium perplexans_ - Rocky Mountain Thistle
- _Cirsium pitcheri_ - Pitcher's Thistle, Sand Dune Thistle
- _Cirsium praeteriens_ - Palo Alto Thistle, Lost Thistle
- _Cirsium proteanum_ - Red Thistle
- _Cirsium pulcherrimum_ - Wyoming Thistle
- _Cirsium pumilum_ - Pasture Thistle
- _Cirsium pyrenaicum_
- _Cirsium quercetorum_ - Alameda County Thistle
- _Cirsium remotifolium_ - Fewleaf Thistle
    - _Cirsium remotifolium_ var. _remotifolium_ - Fewleaf Thistle
- _Cirsium repandum_ - Sandhill Thistle
- _Cirsium rhaphilepis_
- _Cirsium rhothophilum_ - Surf Thistle
- _Cirsium rivulare_
- _Cirsium rothrockii_ - Rothrock's Thistle
- _Cirsium rusbyi_ - Rusby's Thistle
- _Cirsium rydbergii_ - Rydberg's Thistle
- _Cirsium scabrum_ - Rough Thistle
- _Cirsium scapanolepis_ - Mountain Slope Thistle
- _Cirsium scariosum_ - Meadow Thistle
- _Cirsium scopulorum_ - Mountain Thistle
- _Cirsium segetum_
- _Cirsium serrulatum_
- _Cirsium spinosissimum_
- _Cirsium subniveum_ - Gray Thistle, Jackson Hole Thistle
- _Cirsium tanakae_
- _Cirsium texanum_ - Texas Thistle
- _Cirsium tioganum_ - Stemless Thistle
- _Cirsium tuberosum_ - Tuberous Thistle.  Similar to _Cirsium dissectum_ (Meadow Thistle).
- _Cirsium turneri_ - Cliff Thistle
- _Cirsium undulatum_ - Gray Thistle, Wavy-leaf Thistle, Wavyleaf Thistle
    - _Cirsium undulatum_ var. _tracyi_ - Tracy's Thistle, Wavyleaf Thistle
    - _Cirsium undulatum_ var. _undulatum_ - Wavyleaf Thistle
- _Cirsium validus_ - Graceful Thistle
- _Cirsium vernale_ - Spring Thistle
- _Cirsium vinaceum_ - Sacramento Mountain Thistle, Sacramento Mountains Thistle
- _Cirsium virginense_ - Virgin Thistle
- _Cirsium virginianum_ - Virginia Thistle
- _Cirsium vulgare_ - Bull Thistle, Spear Thistle, Common Thistle, Fuller's Thistle (syn. _C. lanceolatum_)
- _Cirsium wheeleri_ - Wheeler's Thistle
- _Cirsium wrightii_ - Wright's Thistle
- Hybrids
- _Cirsium × canalense_ - Canal Thistle
- _Cirsium × crassum_ - Thistle
- _Cirsium × erosum_ - Glory Thistle
- _Cirsium × iowense_ - Iowa Thistle
- _Cirsium × vancouverense_ - Vancouver Thistle