Flower Color: Pink or purple, lavender or white; disk flowers only, large showy flower heads 2 or 3 inches wide, surrounded by sharp spine tipped bracts or phyllaries; solitary or 2 or 3 flower heads on tips of peduncles, loose corymb-like arrays.
Flowering Season: March to September, successful blooms following winter and spring rains and again after heavy summer monsoon rainfall.
Elevation: 1,000 to 6,500 feet.
Habitat Preferences: Plains, mesas, rocky hillsides, foothills, roadsides and washes.
Recorded Range: In the United States in AZ, CA, CO, NM, NV and UT and in northwest Mexico. New Mexico Thistle is scattered throughout most of Arizona.
Invasive/Noxious Weed Information: In North America the genus Cirsium is listed as a Noxious Weed by the States of Arkansas and Iowa. Plants included here are invasive or noxious. ∗ See Comments section below.
Wetland Indicator: No data available.
Threatened/Endangered Information: No data available
Genus Information: In North America there are 91 species for Cirsium. Worldwide, The Plant List includes 481 accepted species names and a further 812 scientific names of infraspecific rank for the genus. The genus Cirsium was published by Philip Miller in 1754.
In the Southwestern United States: Arizona and New Mexico each have 19 species of genus, California has 27 species, Nevada has 16 species, Texas has 12 species, Utah has 23 species. All data approximate and subject to revision.
Comments: A southwestern species, the geographic range of New Mexico Thistle suggests it to be a Mojave Desert species although it is native to and common in both the Mojave and Sonoran Deserts.
∗The genus Cirsium has received adverse notoriety because of the introduction of two thistles native to Europe and now widespread throughout North America. The Canadian Thistle, Cirsium arvense and and the Bull Thistle, Cirsium vulgare are both listed as noxious primarily by agricultural interests.
Most southwestern native thistles, including Mojave Thistle, are non-aggressive; non-invasive and beneficial as pollinators that have evolved to thrive without becoming weedy. Many native thistles are now threatened with some species at risk of extinction.
For a comprehensive thoroughly documented review of New Mexico Thistle see the USDA USFS Fire Effects Information System, or FEIS.
Thistles of the genus Cirsium are regularly visited by many wildlife species such as small mammals, hummingbirds and nectar-feeding bats. Also the seeds are attractive to small mammals and finches such as American goldfinch.
Special Value to Native Bees, Butterflies and Insects
Thistles of the genus Cirsium are important as a group as they are frequently visited by pollinators such as Native bees, bumblebees and a very large numbers of insects and butterflies. "Monarch butterflies visit native thistle flowers more than any other wildflowers in some regions during their migration back to Mexico". They are also heavily used as food plants by the larvae of some Lepidoptera (butterfly) species. In addition to food Cirsium also provides nesting material and structure for Native bees and other insects.
The genus Cirsium is derived from the Greek words kirsion "a kind of thistle" in turn from kirsos, "a swollen vein or welt," as thistles are used as a remedy for such issues. The genus Cirsium was published by Philip Miller in 1754.
The species epithet neomexicanum is a direct reference meaning of or from or otherwise honoring New Mexico.
New Mexico Thistle has been used for medicinal purposes by Navajo and Yavapai Indians.
Navajo Drug, Febrifuge; Plant used for chills and fevers.
Navajo, Ramah Drug, Eye Medicine; Cold infusion of root used as a wash for eye diseases.
Navajo, Ramah Drug, Panacea; Cold infusion of plant taken when one 'feels bad all over; and root used as a 'life medicine.'
Navajo, Ramah Drug, Veterinary Aid; Cold infusion of root used as a wash for livestock with eye diseases.
Yavapai Food, Unspecified; Raw, peeled stems used for food.
See species account from Native American Ethnobotany, University of Michigan, Dearborn.