Carnegiea gigantea, Giant Saguaro

Southwest Desert Flora

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

Cirsium ochrocentrum, Yellowspine Thistle

Encelia frutescens, Button Brittlebush

Button Brittlebush is like Brittlebush, but the flowers typically are disk only, meaning they have no ray flowers as seen on Brittlebush. The phyllaries, subtending the flower, are narrowly lanceolate. Encelia frutescens Button Brittlebush has flowers and leaves that are fed on by the Desert Blister Beetle (Lytta magister) seen here. These beetles are found in the southwestern United States. Encelia frutescens Button Brittlebush is a native perennial shrub or subshrub with green or gray-green leaves, elliptic or narrowly oval in shape. Leaves are mostly alternate and drought deciduous. Encelia frutescens Button Brittlebush blooms from January to September in Arizona and from February to May and again August to September in California. Encelia frutescens Button Brittlebush grows up to 4 or 5 feet tall in elevations up to 4,000 preferring high deserts, rocky slopes, desert washes, flats, slopes mesas and roadsides. Encelia frutescens

Scientific Name: Encelia frutescens
Common Name: Button Brittlebush

Also Called: Bush Encelia, Green Brittlebush, Rayless Encelia (Spanish: Hierba del Bazo, Rama Blanca)

Family: Asteraceae, Sunflower Family

Synonyms: (Encelia farinosa var. phenicodonta, Encelia farinosa var. radians Brandegee, Encelia frutescens var. frutescens, Encelia frutescens forma virginensis, Encelia frutescens var. virginensis, Simsia frutescens)

Status: Native

Duration: Perennial

Size: Up to 4 feet (122 cm) or more

Growth Form: Shrub or subshrub; rounded profile with slender white stems from short trunks, new stems smooth (glabrous) older stems with split or cracked bark (fissured).

Leaves: Green, dark green to gray-green; leaves alternate along stems; blades elliptic or narrowly ovate; leaves simple, generally upper leaves with short stems ( petioles), drought deciduous, rough with small stiff coarse hairs (strigose).

Flower Color: Yellow, mostly disk flowers, ray flowers less common, solitary flower heads on tips of long strigose flowering stalks (peduncles); bracts or phyllaries surrounding flowering heads not equal, linear or lanceolate; fruit an airborne cypsela.

Flowering Season: January to September in Arizona; February to May and again August to September in California.

Elevation: Sea level to 4,000 feet (0-1,219 m); up to 2,500 feet (0-800 m) in California.

Habitat Preferences: High deserts, rocky slopes, desert washes, flats, slopes, mesas and roadsides.

Recorded Range: Encelia frutescens is found in the southwestern United States in AZ, CA and NV and also in Baja California and northwest Mexico. In Arizona it is found throughout much of the state although few records for the central east and the southeast areas.

North America & US County Distribution Map for Encelia frutescens.

North America species range map for Button Brittlebush, Encelia frutescens:
North American range map courtesy of Virginia Tech, Dept. of Forest Resources & Environmental Conservation

Button Brittlebush, Encelia frutescens: 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 8 species of Encelia and includes a further 8 infraspecific rank for the genus. World wide, The Plant List includes 20 accepted species names and includes a further 29 infraspecific rank for the genus.

The genus Encelia was published in 1763 by Michel Adanson.

In the Southwestern United States: Arizona, Nevada and Utah each have 4species of Encelia, California has 5 species, New Mexico has 2 species and Texas has 1 species. Data approximate and may be revised.

Comments: Button Brittlebush is primarily a Mojave Desert species and also found in the higher elevations of the Sonoran Desert. It may start blooming early in January and continue well into September following sufficient monsoon rainfall. In burned and disturbed sites, Button Brittlebush reqcts quickly to colonize the area.

The type species for Encelia frutescens is from Agua Caliente, Maricopa County (Emory in 1846), Arizona.

For a comprehensive well documented review of Encelia frutescens see the USDA USFS Fire Effects Information System, or FEIS.

Button Brittlebush is closely related to Brittlebush which has cymose or panicled flower heads with a mostly smooth (glabrous) inflorescence and its leaves are densely whitish. Button Brittlebush has solitary heads and pubescent (strigose) stems and the leaves are not whitish.

In Southwest Desert Flora also see similar species: Brittlebush, Encelia farinosa, Virgin River Brittlebush, Encelia virginensis, Hairy Desertsunflower, Geraea canescens and Parish's Goldeneye, Bahiopsis parishii.

Importance to Wildlife, Birds and Livestock
Encelia frutescens, in arroyo habitats, is an important food source and cover for the Desert Tortoise in periods of low moisture. Seeds of similar species of Encelia (farinosa) are eaten by birds and small mammals.

Special Value to Native bees, Butterflies and Insects
Encelia frutescens flowers and plants may be visited by native bees, butterflies and/or insects in search of food, nectar or cover.

The genus Encelia (Ence'lia:) was named in honor of Christoph Entzelt (1517-1583), German physician, historian and naturalist, and early Lutheran clergyman.

The genus Encelia was published in 1763 by Michel Adanson.

The species epithet frutescens (frutes'cens:) means shrubby.


Date Profile Completed: 10/9/2012; updated 07/10/2020
Arizona Flora, Kearney, Thomas H., Peebles, Robert H., 1960, University of California Press, Berkley and Los Angeles
U.S. Dept. of Agriculture, Natural Resources Conservation Service on-line database (accessed 07/05/2020.
The Plant List (2013). Version 1.1. Published on the Internet; (accessed 07/05/2020).
Esser, Lora L. 1993. Encelia frutescens. In: Fire Effects Information System, [Online]. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory (Producer). Available: [2020, July 10].
David J. Keil & Curtis Clark 2012, Encelia frutescens, in Jepson Flora Project (eds.) Jepson eFlora, /eflora/eflora_display.php?tid=2558, accessed on July 09, 2020.
Curtis Clark, FNA | Family List | FNA Vol. 21; 3. Encelia frutescens (A. Gray) A. Gray, Proc. Amer. Acad. Arts. 8: 657. 1873. | Asteraceae; Flora of North America Editorial Committee, eds. 1993+. Flora of North America North of Mexico. 16+ vols. New York and Oxford.
Wiggins 1964, FNA 2006, Benson and Darrow; Editor; S.Buckley 2010from SEINet Field Guide, on-line; (accessed 07/10/2020).
Wikipedia contributors, 'Encelia frutescens', Wikipedia, The Free Encyclopedia, 21 March 2018, 15:22 UTC, [accessed 10 July 2020]
SEINet synonyms, scientific names, geographic locations, general information.
Etymology:Michael L. Charters California Plant Names: Latin and Greek Meanings and Derivations; A Dictionary of Botanical and Biographical Etymology - (accessed 07/05/2020)