Carnegiea gigantea, Giant Saguaro

Southwest Desert Flora

Home to the plants of the Sonoran, Chihuahuan and Mojave Deserts

Cirsium ochrocentrum, Yellowspine Thistle

Cirsium grahamii, Graham's Thistle

Cirsium grahamii, Graham's Thistle, Southwest Desert Flora Cirsium grahamii, Graham's Thistle, Southwest Desert Flora Cirsium grahamii, Graham's Thistle, Southwest Desert Flora   Cirsium grahamii, Graham's Thistle, Southwest Desert Flora CCirsium grahamii, Graham's Thistle, Southwest Desert Florairsium grahamii, Graham's Thistle   Cirsium grahamii, Graham's Thistle, Southwest Desert Flora

Scientific Name: Cirsium grahamii
Common Name: Graham's Thistle
Also Called:
Family: Asteraceae, Sunflower Family
Synonyms: ( )
Status: Native
Duration: Perennial
Size: To 3 feet.
Growth Form: Forb/herb; erect, single stem, all parts spiny.
Leaves: Green; oblanceolate to oblong-elliptical, spiny over much of leaf, margins entire, coarsely dentate or pinnatifid, lobes with or without teeth, basal leaves sessile or with narrow wings, basal leaves remain green and healthy at bloom.
Flower Color: Deep purple; single flower head or clusters of 3 to 5, bracts (phyllaries subtending flower head are tipped with many long stiff spines; fruit is an achene.
Flowering Season: August to October, blooms following summer monsoon rainfall.
Elevation: 6,500 to 7,500 feet, a narrow range of elevation.
Habitat Preferences: Various high elevation habitats including pine forest openings, evergreen oak communities, closed grassy basins, meadows and other damp areas.
Recorded Range: A rare thistle in the United States with a very limited distribution in northern and southern Arizona and central New Mexico. Graham’s Thistle is also recorded in northern Mexico.

U.S. Weed Information: No data available.
Invasive/Noxious Weed Information: No data available.
Wetland Indicator: No data available.
Threatened/Endangered Information: No data available

Genus Information: 95 species in Cirsium throughout all of North America, Puerto Rico Newfoundland, Greenland. 19 species recorded in Arizona.

Comments: There is little botanical information for Graham’s Thistle, which, like many native thistles have limited geographic distribution and are not an aggressive or noxious weed as notorious thistles. It appears to be more specialized in its habitat requirements as suggested by its extremely limited geographic range. Like most thistles, Graham’s Thistle attracts many different insects including bees, wasps and butterflies. Superficially similar in appearance to Wheeler’s Thistle, Cirsium wheeleri.

In Southwest Desert Flora also see; Arizona Thistle, Cirsium arizonicum, New Mexico Thistle, Cirsium neomexicanum and Yellowspine Thistle, Cirsium ochrocentrum.
Date Profile Completed: 8/11/2012; Updated, 07/25/2015
References:
Integrated Taxonomic Information System, ITIS, Date Generated: Sun Jul 8 2012 02:20:45 MDT,
http://www.itis.gov/
Arizona Flora, Kearney, Thomas H., Peebles, Robert H., 1960, University of California Press, Berkley and Los Angeles
David J. Keil, FNA | Family List | FNA Vol. 19, 20 and 21 | Asteraceae | Cirsium, Flora of North America Editorial Committee, eds. 1993+. Flora of North America North of Mexico. 16+ vols. New York and Oxford. (accessed 8/11/12)
SEINet for synonyms, scientific names and recorded geographic locations, http://swbiodiversity.org/seinet/