Cirsium eatonii

Cirsium eatonii
Cirsium eatonii var. clokeyi in Southern Nevada
Scientific classification
Kingdom:	Plantae
(unranked):	Angiosperms
(unranked):	Eudicots
(unranked):	Asterids
Order:	Asterales
Family:	Asteraceae
Tribe:	Cynareae
Genus:	Cirsium
Species:	C. eatonii
Binomial name
Cirsium eatonii (A.Gray) B.L.Rob.
Synonyms[1]
Synonymy Carduus leiocarpus A.Heller Carduus leiocephalus (D.C.Eaton) A.Heller Cirsium eatonii var. harrisonii S.L.Welsh Cirsium eriocephalum var. leiocephalum D.C.Eaton Cnicus eatonii A.Gray Carduus hookerianus var. eriocephalus (A.Gray) A.Nelson, syn of var. eriocephalum Carduus scopulorum Greene, syn of var. eriocephalum Cirsium eriocephalum A.Gray 1864 not Wallr. 1840, syn of var. eriocephalum Cirsium hookerianum var. eriocephalum (A.Gray) A.Nelson, syn of var. eriocephalum Cirsium scopulorum (Greene) Cockerell, syn of var. eriocephalum Cirsium scopulorum (Greene) Cockerell ex Daniels , syn of var. eriocephalum Cnicus eriocephalus A.Gray, syn of var. eriocephalum Carduus hesperius A.Heller, syn of var. hesperium Carduus hookerianus var. hesperius (Eastw.) A.Nelson, syn of var. hesperium Cirsium hesperium (Eastw.) Petr., syn of var. hesperium Cnicus hesperius Eastw., syn of var. hesperium Carduus polyphyllus Rydb., syn of var. murdockii Carduus tweedyi Rydb., syn of var. murdockii Cirsium murdockii (S.L.Welsh) Cronquist, syn of var. murdockii Cirsium polyphyllum (Rydb.) Petr., syn of var. murdockii Cirsium tweedyi (Rydb.) Petr., syn of var. murdockii Cirsium peckii L.F.Hend., syn of var. peckii

Cirsium eatonii, commonly known as Eaton's thistle or mountaintop thistle, is a North American species of flowering plants in the aster family.^[2][3]

The species has been found in Idaho, Montana, New Mexico, Wyoming, Nevada, Utah and Colorado.^[4]

Description

Cirsium eatonii is an erect herb up to 150 cm (60 inches or 5 feet) tall. Leaves are generally hairless but the entire foliage is covered with many long, white spines. One plant produces several flower heads with pink to purple flowers. The species grows in grasslands, sagebrush steppes, open savannahs, etc.^[3]

Varieties^[1][3]

A number of varieties have been identified, which include:

• Cirsium eatonii var. clokeyi - Clokey thistle, Spring Mountains thistle, white-spine thistle - Nevada
• Cirsium eatonii var. eatonii - Nevada, Utah
• Cirsium eatonii var. eriocephalum - alpine thistle, mountain thistle - Colorado, New Mexico, Utah
• Cirsium eatonii var. hesperium - tall mountain thistle - Colorado
• Cirsium eatonii var. murdockii - northern mountain thistle - Colorado, Idaho, Montana, Nevada, Utah, Wyoming
• Cirsium eatonii var. peckii - ghost thistle, Steens Mountain thistle - Nevada, Oregon
• Cirsium eatonii var. viperinum - Snake Range thistle - Nevada

References

1. The Plant List, Cirsium eatonii (A.Gray) B.L.Rob.
2. "Taxon: Cirsium eatonii (A. Gray) B. L. Rob.". Germplasm Resources Information Network (GRIN). United States Department of Agriculture, Agricultural Research Service, Beltsville Area. Retrieved 11 March 2012.
3. "Cirsium eatonii". Flora of North America. efloras.org. Retrieved 11 March 2012.
4. "Cirsium eatonii (A. Gray) B.L. Rob.". USDA PLANTS database. Retrieved 11 March 2012.

External links

• Media related to Cirsium eatonii at Wikimedia Commons
• United States Department of Agriculture Plants Profile for Cirsium eatonii (Eaton's thistle)