Carnegiea gigantea, Giant Saguaro

Southwest Desert Flora

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

Cirsium ochrocentrum, Yellowspine Thistle

Agoseris heterophylla, Annual Agoseris

Agoseris heterophylla, Annual Agoseris Agoseris heterophylla, Annual Agoseris    Agoseris heterophylla, Annual Agoseris Agoseris heterophylla, Annual Agoseris    Agoseris heterophylla, Annual Agoseris

Scientific Name: Agoseris heterophylla
Common Name: Annual Agoseris
Also Called: Annual Goatsbeard and Mountain Dandelion.
Family: Asteraceae, Sunflower Family
Synonyms: (Troximon chilense, Troximon heterophyllum)
Status: Native
Duration: Annual
Size: Up to 16 inches in form of a flowering stalk (peduncle) or scape.
Growth Form: Forb/herb, erect, small dandelion like plant covered in small white-hairy pubescence, milky sap.
Leaves: Light green or greenish-whitish, basal rosette leaves, about 6 inches long and narrow, about ½ inch wide, leaf shape variable, narrow, oblanceolate, entire, toothed or pinnatifid; variable white-hairy pubescence overall.
Flower Color: Yellow; ray ligule flowers only, heads solitary borne on single erect stem, several stems from the base, fruit is an achene, pappus of white bristles like a dandelion.
Flowering Season: March to May.
Elevation: 2,500 to 5,000 feet.
Habitat Preferences:Open areas in higher elevations, drier habitats in the plains, mesas and canyons in Arizona.
Recorded Range: Western United States and British Columbia: In the United States in AZ, CA, CO, ID, MT, NM, NV, OR, UT and WA.

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: Eight species in Agoseris primarily in the western half of North America, and in Michigan and Ontario. Three species in Arizona. Three varieties in Agoseris heterophylla, one variety in Arizona;
Agoseris heterophylla var. heterophylla, Annual Agoseris.

Comments: Anual Agoseris is not a desert species. It belongs to a small genus of basal leaves plants resembling the common dandelion with their similar yellow flowers and puff ball seed heads. Adding to confusion are the common names for Agoseris such as Mountain- and False-Dandelion. (See Common Dandelion, Taraxacum officinale.

Annual Agoseris is one of three species of Agoseris native to Arizona which also includes Pale Agoseris Agoseris glauca, and Orange Agoseris, Agoseris aurantiaca.

Date Profile Completed: 6/5/2013; Updated, 07/25/2015
U.S. Dept. of Agriculture, Natural Resources Conservation Service on-line database
Arizona Flora, Kearney, Thomas H., Peebles, Robert H., 1960, University of California Press, Berkley and Los Angeles
1993, The Jepson Manual, Citation: (accessed 06/04/2013)
Gary I. Baird, FNA | Family List | FNA Vol. 19, 20 and 21 | Asteraceae | Agoseris, Page 323, 324, 331, 332, Flora of North America Editorial Committee, eds. 1993+. Flora of North America North of Mexico. 16+ vols. New York and Oxford. (accessed 06/05/2013)
SEINet for synonyms, scientific names and recorded geographic locations,