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  to Eurasia and northern Africa.  There are about 60  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

## References