Southwest Desert Flora

Scientific Name: Eriogonum fasciculatum
Common Name: Flat-top Buckwheat
Also Called: California Buckwheat, Eastern Mojave Buckwheat, Flattop Buckwheat, Mojave Buckwheat, Yellow Buckwheat (Spanish: Maderista, Valeriana, Gordo Lobo)
Family: Polygonaceae, Buckwheat Family
Synonyms: (Eriogonum fasciculatum subsp. fasciculatum )
Status: Native
Duration: Perennial
Size: Up to 3 feet and almost 4 or 5 feet wide.
Growth Form: Shrub, subshrub; plants shrubby, stems decumbent.
Leaves: Grayish-green; decumbent; leaves pilose or villous above (adaxial); leaves often fascicled; leaves in clusters at nodes, leaf shape variable from linear to oblanceolate, rolled under (revolute), bottom (abaxial) of leaves white-tomentose.
Flower Color: White, pink; flowers slightly fragrant, flowers in flat-toped clusters (terminally); inflorescence cymemose; canescent, perianth with stalk-like base; fruit glabrous.
Flowering Season: March to June.
Elevation: 1,00 to 4,500 feet.

Habitat Preferences: Dry rocky slopes, canyons in scrub communities and washes.

Recorded Range: Eriogonum fasciculatum is found in the southwestern United States in CA, AZ, NV, UT. It also has large populations in Baja California and northwest Mexico. In Arizona it occurs throughout the western ½ of the state and in Graham county.

North America & US County Distribution Map for Eriogonum fasciculatum.

U.S. Weed Information: No information available.
Invasive/Noxious Weed Information: No information available.
Wetland Indicator: No information available.
Threatened/Endangered Information: No information available.

Eriogonum is found throughout Arizona and entire southwest with 58 species in Arizona, 115 species in California, 36 species in New Mexico, 79 species in Nevada and 67 species in California. All data is approximate and subject to taxonomic changes.

There are 4 varieties in Eriogonum fasciculatum;
Eriogonum fasciculatum var. fasciculatum, Eastern Mojave Buckwheat (CA),
Eriogonum fasciculatum var. flavoviride, Eastern Mojave Buckwheat (CA),
Eriogonum fasciculatum var. foliolosum, Eastern Mojave Buckwheat (AZ, CA),
Eriogonum fasciculatum var. polifolium, Eastern Mojave Buckwheat (AZ, CA, NV, UT).

Comments: Flat-top Buckwheat is one of the more dominant low- and high-desert species primarily in the Sonoran Desert. However, "foliolosum" and "polifolium" are prevalent in both the Mojave and Sonoran Deserts (Both of these varieties are found in Arizona). All forms are quite variable in appearance.

Various species of Eriogonum play host to the larvae (caterpillar) of several butterflies including the Mormon Metalmark butterfly (Apodemia mormo), the Rocky Mountain dotted-blue (Euphilotes ancilla) and the Lupine Blue (Aricia lupini).

In Southwest Desert Flora also see Abert's Buckwheat, Eriogonum abertianum, Skeleton Weed, Eriogonum deflexum, Desert Trumpet, Eriogonum inflatum, Little Deserttrumpet, Eriogonum trichopes, Sulphur-flower Buckwheat, Eriogonum umbellatum and Wright Buckwheat, Eriogonum wrightii.

Flat-top Buckwheat is or has been used by North American indigenous peoples. Here are a few of the many uses:
Coahuilla Drug, Analgesic, Decoction of leaves taken for headache and stomach pain;
Costanoan Drug, Urinary Aid, Decoction of plant used for urinary problems;
Diegueno Drug, Antidiarrheal, Decoction of flowers given to babies for diarrhea;
Zuni Drug, Dermatological Aid; Poultice of powdered root applied to cuts and arrow or bullet wounds.
See ethno-botanical uses at Native American Ethnobotany, University of Michigan, Dearborn.