Gutierrezia californica |
Gutierrezia arizonica |
|
---|---|---|
California matchweed, matchweed, San Joaquin snakeweed, snakeweed |
Arizona snakeweed |
|
Habit | Subshrubs, 20–70 cm. | Annuals, 12–30 cm. |
Stems | glabrous or minutely hispidulous. |
glabrous. |
Leaves | basal absent at flowering; cauline blades 1-nerved, filiform to linear, 0.5–1(–1.3) mm wide, reduced distally, often reduced in arrays to tiny, curved bracts. |
basal sometimes persistent, proximal usually absent at flowering; cauline blades 1-nerved, narrowly elliptic-oblanceolate to elliptic-lanceolate, 1–2 mm wide, reduced distally. |
Involucres | turbinate to cylindric-turbinate (longer than diams.), 2.5–4 mm diam. |
campanulate, 4–7 mm diam. |
Ray florets | 4–13; corollas yellow, 2.5–7 mm. |
8–15; corollas white, drying light yellow or reddish, 6–7.5 mm. |
Disc florets | (4–)6–13. |
(16–)20–30(–40). |
Heads | borne singly or (sometimes subsessile and in clusters of 2–3) in loose arrays. |
borne singly or in loose, open arrays. |
Cypselae | 2–2.8 mm, faces densely strigoso-sericeous; pappi of 1–2 series of lanceolate to oblanceolate scales 1.5–2.2 mm. |
0.9–1.6 mm, faces without oil cavities, densely strigoso-sericeous (hair apices prominently bulbous-capitate); pappi coroniform or of 1 series of basally connate scales 0.1–0.3 mm (obscured by cypsela indument). |
Phyllary | apices flat. |
apices flat. |
2n | = 16, 24. |
= 8. |
Gutierrezia californica |
Gutierrezia arizonica |
|
Phenology | Flowering Apr–Nov(–Dec). | Flowering (Feb–)Mar–May. |
Habitat | Grassland, chaparral, oak woods, alluvium, rocky slopes, sometimes over serpentine | Sandy or sandy-rocky plains or washes |
Elevation | 100–400 m (300–1300 ft) | 200–1300 m (700–4300 ft) |
Distribution |
CA; Mexico (Baja California)
|
AZ; Mexico (Sonora) |
Discussion | Following D. D. Keck (1960) and M. A. Lane (1985), Gutierrezia californica is treated here as a variable taxon that includes G. divergens. O. T. Solbrig (1965, 1970) considered G. californica to be a narrow endemic restricted to serpentine outcrops of the San Francisco Bay region, in which case the earliest name for the more widely distributed plants, including those of Mexico, is G. divergens Greene. Molecular evidence (Y. Suh and B. B. Simpson 1990) tentatively supports the recognition of the serpentine endemic; more detailed sampling would be needed for an objective decision. The morphologic differences are quantitative and overlapping. Intergrades between G. californica in the broad sense and G. sarothrae are said to occur in California (Lane 1993). (Discussion copyrighted by Flora of North America; reprinted with permission.) |
|
Source | FNA vol. 20, p. 93. | FNA vol. 20, p. 90. |
Parent taxa | ||
Sibling taxa | ||
Synonyms | Brachyris californica, G. bracteata, G. divergens, Xanthocephalum californicum | Greenella arizonica, Xanthocephalum arizonicum |
Name authority | (de Candolle) Torrey & A. Gray: Fl. N. Amer. 2: 193. (1842) | (A. Gray) M. A. Lane: Sida 8: 313. (1980) |
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