''Cirsium cymosum'' is a
North America
North America is a continent in the Northern Hemisphere and almost entirely within the Western Hemisphere. It is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South America and the Car ...
n species of
thistle known by the common name peregrine thistle. It is native to the western United States, where it has been found in
California,
Oregon,
Nevada,
Utah,
Idaho,
Wyoming, and
Montana.
''Cirsium cymosum'' is a
biennial or
perennial herb with a maximum height just . It is coated in soft and coarse hairs and sometimes cobwebby fibers. The spiny leaves may reach in length, especially toward the base of the stem. They are deeply cut into lobes which are lined with sharp teeth. The
inflorescence is a cluster of
flower heads
A pseudanthium (Greek for "false flower"; ) is an inflorescence that resembles a flower. The word is sometimes used for other structures that are neither a true flower nor a true inflorescence. Examples of pseudanthia include flower heads, compos ...
each up to 3 centimeters long and 5 wide. The head is lined with sticky, spiny
phyllaries and filled with dull white flowers. The fruit is an
achene
An achene (; ), also sometimes called akene and occasionally achenium or achenocarp, is a type of simple dry fruit produced by many species of flowering plants. Achenes are monocarpellate (formed from one carpel) and indehiscent (they do not ope ...
with a dark-colored body just under a centimeter long and a
pappus of hairs up to in length.
[Flora of North America, ''Cirsium cymosum'' (Greene) J. T. Howell]
/ref>
;Varieties[
*''Cirsium cymosum'' var. ''canovirens'' (Rydb.) D.J.Keil - most of species rangeFlora of North America: var. ''canovirens'']
/ref>
*''Cirsium cymosum'' var. ''cymosum'' - California, Nevada, Oregon
References
External links
Jepson Manual TreatmentCalphotos Photo gallery, University of California
cymosum
Flora of the Western United States
Plants described in 1897
Flora without expected TNC conservation status
{{Cynareae-stub