Southwest Desert Flora

Scientific Name: Eriogonum deflexum
Common Name: Skeleton Weed
Also Called: Flatcrown Buckwheat, Flat-toped Buckwheat, Flat-topped Buckwheat, Skeletonweed, Skeletonweed Buckwheat
Family: Polygonaceae, Buckwheat Family
Synonyms: (Eriogonum deflexum subsp. deflexum)
Status: Native
Duration: Annual
Size: Up to 6 feet or more.
Growth Form: Forb/herb; erect to spreading.
Leaves: Green; basal, margins entire; leaf petiole ½ to 3 inches, leaves rounded, cordate or reniform; bottom surface of leaf (abaxial) white woolly or white-tomentose, top surface of leaf (adaxial) less tomentose to floccose, grayish to greenish.
Flower Color: White to pink or pinkish; reddish or greenish midribs; cyme-like inflorescence, flat-topped, glabrous, the calyx and corolla look very similar and are collectively referred to as a perianth; fruit a brown, smooth achene.
Flowering Season: Summer, fall or year-round with sufficient moisture.
Elevation: 4,000 and lower.

Habitat Preferences: Very abundant, roadsides sandy desert scrub and semi-desert parts of the state.

Recorded Range: Eriogonum deflexum is found in the southwest United States in AZ, CA, NV, NM, UT. In Arizona it is found throughout most of the state. It is also native to Baja California and northwest Mexico.

North America & US County Distribution Map for Eriogonum deflexum.

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. The genus Eriogonum is well represented in the southwest and in Arizona both for species numbers and individual populations.

There are 4 varieties in Eriogonum deflexum:
Eriogonum deflexum var. baratum, Flatcrown Buckwheat (CA, NV);
Eriogonum deflexum var. deflexum, Flatcrown Buckwheat (AZ, CA, NM, NV, UT);
Eriogonum deflexum var. nevadense, Nevada Buckwheat (CA, NV, UT);
Eriogonum deflexum var. rectum, Flatcrown Buckwheat (CA only);

Comments: Skeleton Weed is extremely drought resistant and in dry years when other plants will not bloom or have perished, these plants appear to thrive. According to Flora of North America, Skeleton Weed is common and weedy throughout most of its known range.

This species provides an important source of seed for birds and 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, Flat-top Buckwheat, Eriogonum fasciculatum, Desert Trumpet, Eriogonum inflatum, Little Deserttrumpet, Eriogonum trichopes, Sulphur-flower Buckwheat, Eriogonum umbellatum and Wright Buckwheat, Eriogonum wrightii.