Mike Lyle schreef
As AUE regulars may know, but sci.bio.botany readers may not, I like
tracing the history of our words; and have a healthy suspicion of what
may seem obvious origins. "Saltcedar", for example, seems a quite
obvious name given the American tendency to use "cedar" rather
promiscuously and the genus's well-known tolerance of saline
conditions; but there are plenty of English words and expressions
which superficially look as "logical", but which turn out on
investigation to have quite different origins. I wanted to be sure.

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Common names are quite tricky. I have only limited faith in dictionaries,
although obviously they are great for a quick approximation.
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Even the name *Tamarix gallica* once had an alternative *Tamarix
anglica*, though I think the species hails from SW Europe.

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This is not the right way to put it.
Tamarix anglica is among the synonyms of Tamarix gallica.
The exact relationship between these two names may require some work to dig
out.
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And
*Tamarix germanica* is listed by Hillier as *Myricaria germanica*,
first known to have been cultivated in Britain in 1582.

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Apparently the family has four (five) genera of which Myricaria is one
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The two true
tamarisks most common in British Isles gardens are *pentandra*,
flowering in August,

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According to the Hillier you refer to (1998 edition) it now is called
T.ramosissima (introduced c 1885)
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and *tetrandra*, flowering in May, and don't
appear on the face of it to have been cultivated in Br before the 19C.

But *gallica* is naturalized on some English coasts -- though not,
perhaps, as destructively as in some US zones. I think work needs to
be done on the precise ancestry of British specimens; and I'd like to
know when the various species first arrived in the US.

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Good luck to you. Seems you have your work cut out for you!
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(AUE knows me as a word-hack; but with another hat on I've just done
an estuarine garden in which I wanted to include both the common
species, to give a longer flowering season. Material wasn't available
in the limited time I had, so *tetrandra* it was.)

Mike.

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On a practical note I was interested in seeing that the family is now judged
to belong to Caryophyllales, which is quite fitting considering the sort of
habitats it prefers.
PvR