Gutierrezia texana (DC.) Torr. & Gray
Family: Asteraceae
Texas Snakeweed
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Annuals, 10-80(-100) cm. Stems glabrous. Leaves: proximal usually absent at flowering; cauline blades 1- or 3-nerved, linear , 1.5-4 mm wide, reduced distally. Heads in loose arrays. Involucres campanulate to obconic, 2-4.5 mm diam.. Phyllary apices flat. Ray florets 5-23; corollas yellow, 3-6 mm. Disc florets 7-48 (bisexual and fertile or functionally staminate). Cypselae 1.3-1.8 mm, faces without oil cavities, loosely strigose (hairs appressed, apices acute, microscopically 2-pronged); pappi of 1 series of spreading-erect, oblong to ovate or obovate scales 0.1-0.5 mm (bases sometimes connate, usually shorter in rays, sometimes 0 in var. texana).

Although the two varieties of Gutierrezia texana are similar, the geographic demarcation between them appears to be sharp, and a detailed investigation of their biologic interaction would be interesting.

Allred and Ivey 2012, Correll and Johnston 1970, FNA 2006

Duration: Annual

Nativity: Native

Lifeform: Forb/Herb

General: Annual herbs, 10-80 cm tall; stems smooth and glabrous, branching in the upper half.

Leaves: Alternate along the stem, the blades linear, 1-5 cm long and 1-5 mm wide, glabrous and glutinous.

Flowers: Flower heads small and yellow, located on the tips of branchlets all along the main branches; involucres top-spaped (turbinate) to campanulate (bell-shaped), 3-4 mm high; ray florets 10-15 per flower head, the laminae (ray petals) 3-6 mm long, yellow; disc florets 10-20 per flower head, yellow.

Fruits: Achenes 1.5 mm long, loosely covered with appressed hairs; topped with a pappus of several pointed scales less than 0.5 mm long; pappus is often absent on ray achenes.

Ecology: Found in grassland habitats; flowers in summer and fall.

Distribution: OK, TX, and e NM; south into MEX

Notes: This annual Gutierrezia is considered to be widespread and abundant throughout Texas, though it is quite uncommon in New Mexico where it is occasionally found as far west as Socorro. It is quite similar to G. sphaerocephala, which differs primarily in its papillate-scabrous stems (G. texana has smooth, hairless stems) and by having more disc florets per flower head (20-40 compared to G. texana's 10-20)

Ethnobotany: Unknown

Etymology: Gutierrezia is named for Pedro Gutierrez (Rodriguez), a 19th century Spanish noblemen and botanist; texana refers to the species' range in Texas.

Synonyms: Xanthocephalum texanum,

Editor: AHazelton 2017