Carnegiea gigantea, Giant Saguaro

Southwest Desert Flora

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

Cirsium ochrocentrum, Yellowspine Thistle

Calycoseris wrightii, White Tackstem

White Tackstem is a member of the Asteraceae and one of the prettiest spring wildflowers in the southwest United States deserts. Calycoseris wrightii White Tackstem has straw colored visible glands on the upper parts of the stems and on the flowering parts as well. Note the fine red veins on the lower side of the straps; Calycoseris wrightii White Tackstem blooms in early spring from February to June in the Mojave and Sonoran Deserts. Plants grow up to 12 inches more or less. Calycoseris wrightii White Tackstem has straw colored glands on many flowering parts, seen on a young bud. Calycoseris wrightii White Tackstem has filiform alternate leaves that may grow up to 4 inches in length. This species grows at elevations from 500 to 4,000 feet. Calycoseris wrightii

Scientific Name: Calycoseris wrightii
Common Name: White Tackstem

Also Called: Desert Chickory, Tackstem

Family: Asteraceae, Sunflower Family

Synonyms: ()

Status: Native

Duration: Annual, winter annual.

Size: Up to 12 inches 5-30 cm tall more or less.

Growth Form: Forb/herb; spring annual; low branching (1 to 3 stems); plants generally without surface ornamentation such as hairs, scales or bristles (glabrous) except for conspicuous light straw colored glands on upper part of stem and on the flowering parts; plants with milky sap.

Leaves: Green; leaves arranged alternately along stems; up to 4 inches (10 cm) long, fine, filiform and almost inconspicuous, leaves are pinnately divided, upper leaves greatly reduced to linear bracts.

Flower Color: White, purple-tinged below; showy, flowers 5-toothed strap-petals, (ligulate), fine red veins on bottom (abaxial) of strap; bracts surrounding flower heads gland dotted; fruit a brown, 5-ribbed and beaked cypsela with a pappus of smooth white hairs (bristles)

Flowering Season: March to May; March to June in California and Texas.

Elevation: 500 to 5,000 feet (150-1,600 m).

Habitat Preferences: Common on desert plains in caliche soils, desert washes, rocky mesas and slopes, stream bottoms, limestone gravels, pavement; often in creosote or mesquite associations.

Recorded Range: Calycoseris wrightii is found in the southwestern United States in AZ, CA, NV, NM, extreme western TX (El Paso County) and extreme southwest UT (Washington County). It is also native to Baja California and Sonora Mexico. In Arizona it is found in central, western and southeastern parts of the state.

North America & US County Distribution Map for Calycoseris wrightii.

North America species range map for Calycoseris wrightii:
North American range map courtesy of Virginia Tech, Dept. of Forest Resources & Environmental Conservation

North America species range map for Calycoseris wrightii: Click image for full size map
Click image for full size map

U.S. Weed Information: Unknown
Invasive/Noxious Weed Information: Unknown
Wetland Indicator: Unknown
Threatened/Endangered Information: Unknown

Genus Information: In North America there are 2 species and 2 accepted taxa overall for Calycoseris. World wide, The Plant List includes 2 accepted species names and includes a further 2 infraspecific rank for the genus.

The genus Calycoseris was published by Asa Gray in 1853.

In the Southwestern United States: Arizona, California, Nevada and Utah each have 2 species of Calycoseris, New Mexico and Texas each have 1 species. All data is approximate and subject to taxonomic changes.

Comments: White Tackstem, is considered to be one of the prettiest spring flowers in desert habitats. This species thrives in both the Mojave and Sonoran Deserts.

See White Tackstem, Calycoseris wrightii in the Sonoran Desert Naturalist, Field Guide, Arizonensis.

White Tackstem is similar in size and shape to the closely related Yellow Tackstem, Calycoseris parryi, which differs by its yellow flowers and with a greater preference for the Mojave Desert.

Importance to Wildlife, Birds and Livestock
Tiny wind-borne seeds of Calycoseris wrightii may possibly be eaten by birds and small mammals.

Special Value to Native Bees, Butterflies and Insects
Calycoseris wrightii flowers may be visited by butterflies, bees and other small insects.

The genus Calycoseris (Calycos'eris:) is from the Greek word kalux, “cup”, and seris, a chicory-like genus.

The genus Calycoseris was published by Asa Gray in 1853.

The specific epithet wrightii (wright'ii:) is named in honor of Charles Wright (1811-1885), an American botanical collector that collected plants and sending specimens to Professor Asa Gray at Harvard, eventually becoming one of his most trusted collectors. In 1851, with Gray’s help, Mr. Wright became part of the Mexican Boundary Survey, and helped collect many of the 2,600 species that were sent back to Professor John Torrey for description and identification. His name was honored by George Engelmann who gave it to a cactus, Opuntia wrightii.


Date Profile Completed: 11/18/2016, updated 06/03/2020
Arizona Flora, Kearney, Thomas H., Peebles, Robert H., 1960, University of California Press, Berkley and Los Angeles, California.
U.S. Dept. of Agriculture, Natural Resources Conservation Service on-line database and USGS ITIS search - (accessed 06/02/2020)
The Plant List (2013). Version 1.1. Published on the Internet; (accessed 06/02/2020).
L. D. Gottlieb, FNA | Family List | FNA Vol. 19, 20 and 21 | Asteraceae |Calycoseris; 2. Calycoseris wrightii A. Gray, Smithsonian Contr. Knowl. 5(6): 104, plate 14. 1853.; Flora of North America Editorial Committee, eds. 1993+. Flora of North America North of Mexico. 16+ vols. New York and Oxford.
L.D. Gottlieb 2012, Calycoseris wrightii, in Jepson Flora Project (eds.) Jepson eFlora, /eflora/eflora_display.php?tid=1892, accessed on June 03, 2020.
FNA 2006, Wiggins 1964, Kearney and Peebles 1969, McDougall 1973; Editors; S.Buckley 2010, A.Hazelton 2015 from SEINet Field Guide, on-line; (accessed 06/03/2020).
Native Plant Information Network, NPIN (2013). Published on the Internet - (accessed 06/03/2020). Lady Bird Johnson Wildflower Center at The University of Texas, Austin, TX.
Virginia Tech Dendrology; Department of Forest Resources and Environmental Conservation
SEINet synonyms, scientific names, geographic locations, general information
Michael L. Charters; California Plant Names: Latin and Greek Meanings and Derivations; A Dictionary of Botanical and Biographical Etymology; (accessed 06/03/2020)