Solidago ptarmicoides

           
Upland White Goldenrod

G. F. Ledingham Herbarium
University of Regina

This species superficially resembles members of the Aster genus rather than appearing as a typical Solidago.  The anomalous features of S. ptarmicoides are not taken into account in the key to the Solidago genus in Budd's Flora.  Thus this key requires:
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heads small and numerous, in terminal or axillary clusters; NOT [usually solitary at ends of branches]

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ray florets yellow; NOT [pink, blue, purple, or white]

The above are clearly not true for S. ptarmicoides.  Note that S. ptarmicoides will interbreed with other Solidago species, indicating its membership in that genus.

 
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Ptarmicoides: Answers to key questions in Budd's Flora leading to this species. 
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inflorescence corymbose, with the branches slanting upward, forming a founded or flat-topped inflorescence; NOT [inflorescence a panicle or spike]

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ray florets white or pale yellow; NOT [ray florets yellow]

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ray florets large, 5-8 mm long; NOT [ray florets usually less than 5 mm long]

 

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Solidago: Answers to key questions in Budd's Flora (BF) and Flora of Alberta (FOA) leading to this genus.  These do not include the two incorrect answers described above.
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plants with fibrous roots; NOT with a taproot

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juice watery; NOT milky

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leaves alternate or basal; NOT opposite

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leaves simple; NOT pinnatifid, NOT divided

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leaves never spinescent

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involucral bracts in 2 or more series; NOT [in one series, sometimes with a few much shorter outer ones at the base]

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involucral bracts well imbricated; NOT scarcely imbricated

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receptacle naked (FOA)

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flower heads with both tubular and ray florets

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ligulate flowers pistillate or neuter; NOT perfect

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stamens united to form a tube around the pistil

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pappus composed of hairs; NOT scales, NOT bristles, NOT firm awns, NOT a crown, NOT absent, pappus NOT chaffy

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pappus single, hairs sometimes unequal but not distinctly divided into an inner and outer series of two lengths; NOT [pappus double, hairs of the outer series inconspicuous, distinctly shorter than the inner]