Gutierrezia microcephala (DC.) Gray (1)

by Matthew Fry, Native Plants Class 2003
Common names: Thread leaf snake weed (1)
Family: Asteraceae (1)
Synonymy: Brachyris microcephala, Gutierrezia glomerella Green, Gutierrezia lucida (Green) Green, Gutierrezia sarothrae (Pursh), Britt. & Rusby var. microcephala (DC.) L. Benson Xanthocephalum lucidum Greene, Xanthocephalum microcephalum (DC.) Shinners.(1)
Etymology: The specific epithet means little head.

Identification
Growth form: shrub. (1)
Roots:
Stem: Yellow green stems from woody base branched above with multiple heads ca 1mm in diameter and 3-4 mm in length. (2)
Leaves: Linear to narrowly lanceolate, 2-5 cm (2)
Inflorescence/flowers: 1 or 2 ray flowers, 1or 3 disk flowers, 5-8 phyllaries, lancolate with greenish tips. (2)
Friut:
Similar species: Gutierizzia sarothrae. (1,2,3)

Ecology
Life history: Perennial. (1)
Native/introduced: Native. (1)
Photosynthetic pathway: C3
Phenology: flowers bloom June –October. (3)
Distribution: AZ CA CO NV NM TX UT MEXICO, In the Chihuahuan, Sonoran, Mojave, and Great Basin deserts of the southwestern United States and northern Mexico. It occurs from southwestern Texas; north to extreme southwestern Colorado and south-central Utah; west to southern California; and south to the Mexican states of Sonora, Chihuahua, and Coahuila

Uses
Provides little forage for livestock. (2,3)

References
1. USDA Natural Resource Conservation Service Plants Profile. http://plants.usda.gov/cgi_bin/plant_profile

2. Mcdugall, 1973. Seed Plants of Northern Arizona

3. Epple A.O., Epple L.E., 1995. A Field Guide to the Plants Of Arizona.