No Vikings needed, most bulbs from the pampas (like Rohodophiala bifda) are amazingly hardy in colder climates and probably they had a more southern colder climate original distribution and from there they expanded to their current habitats. They have the genes to survive in their original much harsher climates and here in Argentina they inhabit now deceivingly warmer regions. Inhabiting is way of saying for glyphosate and oter goodies are wiping most of the flora and the fabulous fauna that was so abundant. I know Mr. Monsanto fanciers do not like this to be known but it is the crude reality. It was surprising how accurate Eric's description of the situation time ago was: it was like an X ray of what is taking place all over South America arable regions.