SC - You think it's not period??

[Bronwynmgn at aol.com]

On a slightly different topic (the original one was tomatoes in period 
Turkish cooking), someone tried to convince me this weekend that red-skinned 
potatoes are period because a) they grow wild in North America and could have 
been found here by the Vikings who came to North America; and b) some Norse 
document or saga refers to a "foreign white root".  Needless to say, I was 
not about to accept his word as documentation, and got referred to 
"authenticity police" when I said I would like to evaluate the evidence for 
myself.
So, can anyone give me more detail on where this "documentation" might have 
come from, and what merits it might have?

Brangwayna