A quick paragraph that spells it out clearly and simply.
Once again, German spruce sold to the lutherie world is often spruce sold by German dealers, and whatever species of spruce it actually is tends to come from a variety of sources, including a certain amount historically imported from the US and Canada. Engelmann spruce, for example, is very popular among luthiers and for decades has been exported to Europe where it has been sold back to Americans (among others) as—you guessed it—German spruce. And because of the lutherie trade, spruce from anywhere in Europe is pretty much identified now as German spruce.
Unless you cut the tree yourself or can be absolutely certain where that tree was harvested, it is probably safest to just call it spruce. If you’re certain it grew and was harvested in Europe, there’s no point in getting your turban in a twist over common names. If someone says German spruce, just think, “OK, Picea abies, or European spruce.”
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