Gutierrezia sarothrae |
Gutierrezia texana |
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broom snakeweed, kindlingweed, matchweed, perennial matchweed |
Texas broomweed, Texas snakeweed |
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Habit | Subshrubs, 10–60(–100) cm. | Annuals, 10–80(–100) cm. | ||||
Stems | minutely hispidulous. |
glabrous. |
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Leaves | basal and proximal absent at flowering; cauline blades 1- or 3-nerved, linear to lanceolate, sometimes filiform and fascicled, 1.5–2(–3) mm wide, little reduced distally. |
proximal usually absent at flowering; cauline blades 1- or 3-nerved, linear, 1.5–4 mm wide, reduced distally. |
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Involucres | cylindric to cuneate-campanulate, 1.5–2(–3) mm diam. |
campanulate to obconic, 2–4.5 mm diam.. |
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Ray florets | (2–)3–8; corollas yellow, 3–5.5 mm. |
5–23; corollas yellow, 3–6 mm. |
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Disc florets | (2–)3–9 (usually bisexual and fertile, rarely functionally staminate, corollas tubular-funnelform, lobes erect to spreading or recurved, deltate). |
7–48 (bisexual and fertile or functionally staminate). |
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Heads | (sessile to subsessile in compact glomerules) in dense, flat-topped, corymbiform arrays. |
in loose arrays. |
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Cypselae | 0.8–1.6(–2.2) mm, faces without oil cavities, densely strigoso-sericeous; pappi of 1–2 series of narrowly oblong- to ovate-lanceolate or obovate scales (readily falling, those of discs 1/3–1/2 corollas, shorter on rays). |
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). |
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Phyllary | apices flat. |
apices flat. |
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2n | = 8, 16, 32. |
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Gutierrezia sarothrae |
Gutierrezia texana |
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Phenology | Flowering Jul–Nov(–Jan). | |||||
Habitat | Grasslands, commonly on rocky, open slopes | |||||
Elevation | 50–2900 m (200–9500 ft) | |||||
Distribution |
AZ; CA; CO; ID; KS; MN; MT; ND; NE; NM; NV; NY; OK; OR; SD; TX; UT; WA; WY; AB; MB; SK; Mexico (Baja California, Baja California Sur, Chihuahua, Coahuila, Durango, Nuevo León, San Luis Potosí, Sonora, Zacatecas)
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AR; IL; LA; MO; NM; OK; TX; Mexico
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Discussion | Gutierrezia sarothrae is often abundant in overgrazed pastures; it is naturalized in New York. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Varieties 2 (2 in the flora). 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. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
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Key |
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Source | FNA vol. 20, p. 92. | FNA vol. 20, p. 91. | ||||
Parent taxa | Asteraceae > tribe Astereae > Gutierrezia | Asteraceae > tribe Astereae > Gutierrezia | ||||
Sibling taxa | ||||||
Subordinate taxa | ||||||
Synonyms | Solidago sarothrae, Xanthocephalum sarothrae | Hemiachyris texana, Xanthocephalum texanum | ||||
Name authority | (Pursh) Britton & Rusby: Trans. New York Acad. Sci. 7: 10. (1887) | (de Candolle) Torrey & A. Gray: Fl. N. Amer. 2: 194. (1842) | ||||
Web links |
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