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     There are several dozen Thistles, native and introduced, in the Four Corners area.   Some of these Thistles reproduce from rhizomes; others are biennial, reproducing from seeds.  All are spiny and have only disk flowers.  Most Thistles are large and obvious in plant and in flower.  Some non-native Thistle are serious invaders of meadows and pastures.  

    The genus name, "Cirsium", is Greek for "dilated vein" from the bygone belief that a Thistle distillate opens clogged veins.  

Cirsium tracyi
Synonym: Cirsium tracyiCirsium undulatum variety tracyi.  (Thistle)
Asteraceae (Sunflower Family)

Foothills, montane. Woodlands, openings. Spring.
Near Yellow Jacket Canyon, Canyons of the Ancients National Monument, June 12, 2005.

Cirsium tracyi is a native and very common Thistle, especially in low, semi-desert, dry, open areas.  It has numerous puffy white (sometimes pink-to-lavender purple) flowers which at first appear to be dried seed heads.

This plant was first collected for science by Charles Baker and Samuel Tracy near Mancos, Colorado in 1898 and was at first named Cardus tracyi by Per Axel Rydberg in 1905 and then renamed Cirsium tracyi by Franz Petrak (1886-1973) in 1917.  Several plant authorities, including the USDA Plant Database and Synthesis of the North American Flora now consider Cirsium Tracyi to be a variety of Cirsium undulatum.  It was so designated by Stanley Welsh (of Utah Flora fame) in 1983.  Tracy was a late nineteenth/early twentieth century plant collector. (More biographical information.)

Cirsium tracyi

Cirsium tracyi

Synonym: Cirsium tracyiCirsium undulatum variety tracyi.  (Thistle)
Asteraceae (Sunflower Family)

Foothills. Woodlands, openings. Spring.
Canyons of the Ancients National Monument, June 12, 2005 and near Hovenweep Canyon, May 17, 2004.

Cirsium tracyi
Synonym: Cirsium tracyiCirsium undulatum variety tracyi.  (Thistle)
Asteraceae (Sunflower Family)

Foothills. Woodlands, openings. Spring.
Lone Mesa State Park, August 5, 2008.

The wide spreading basal rosette of early leaves is typical of a number of plants and very typical of Thistles.

Cirsium tracyi
Synonym: Cirsium tracyiCirsium undulatum variety tracyi.  (Thistle)
Asteraceae (Sunflower Family)

Foothills. Woodlands, openings. Spring.
Little Taylor Creek Trail, July 28, 2005.

The drying and dried seed heads are as prickly as the leaves.

Range map © John Kartesz,
Floristic Synthesis of North America

State Color Key

Species present in state and native
Species present in state and exotic
Species not present in state

County Color Key

Species present and not rare
Species present and rare
Species extirpated (historic)
Species extinct
Species noxious
Species exotic and present
Native species, but adventive in state
Eradicated
Questionable presence

Range map for Cirsium tracyi (Cirsium undulatum)