''Cirsium eatonii'', commonly known as Eaton's thistle or mountaintop thistle, is a

North America North America is a continent in the Northern Hemisphere, Northern and Western Hemisphere, Western hemispheres. North America is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South Ameri ...

n species of flowering plants in the family

Asteraceae Asteraceae () is a large family (biology), family of flowering plants that consists of over 32,000 known species in over 1,900 genera within the Order (biology), order Asterales. The number of species in Asteraceae is rivaled only by the Orchi ...

. The species has been found in

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and

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Description

''Cirsium eatonii'' is highly variable. It is an erect herb up to 150 cm (60 inches or 5 feet) tall in some populations. The entire foliage is more or less spiny. One plant produces several flower heads with pink to purple or yellow flowers. The species grows at high elevations in grasslands, sagebrush steppes, open savannahs, etc. ;Varieties A number of varieties have been identified, which include: *''Cirsium eatonii'' var. ''clokeyi'' - Clokey thistle,

Spring Mountains The Spring Mountains are a mountain range of Southern Nevada in the United States, running generally northwest–southeast along the west side of Las Vegas and south to the border with California. Most land in the mountains is owned by the Uni ...

thistle, white-spine thistle. This variety is rare and uncommon. -

*''Cirsium eatonii'' var. ''eatonii'' -

*''Cirsium eatonii'' var. ''eriocephalum'' - alpine thistle, mountain thistle -

*''Cirsium eatonii'' var. ''hesperium'' - tall mountain thistle -

*''Cirsium eatonii'' var. ''murdockii'' - northern mountain thistle -

* ''Cirsium eatonii'' var. ''peckii'' - ghost thistle, Steens Mountain thistle -

Oregon Oregon ( , ) is a U.S. state, state in the Pacific Northwest region of the United States. It is a part of the Western U.S., with the Columbia River delineating much of Oregon's northern boundary with Washington (state), Washington, while t ...

*''Cirsium eatonii'' var. ''viperinum'' - Snake Range thistle -

Cirsium_eatonii_var_eriocephalum_habitus

References

External links

* * * * eatonii Flora of the Western United States Flora of the Great Basin Plants described in 1871 Taxa named by Asa Gray Flora without expected TNC conservation status {{Cynareae-stub