What do those "schweizers" know Malcom? They are all into banking and cow bells and those big horns.
There's poplar and there is poplar. Unless you have the dendrological name for your poplar we ain't certain what the old door is made of. For one thing Europe has much less diverity of trees than North America. Also climate and habitat can make a marked difference in the characteristics of a single type of wood.
And then there is poplar. Tulip Poplar. Yellow Poplar. It's all the same thing and it ain't a member of the "populus" family. It's Lireodendrum Tulipfora. It's the "poplar" you buy at the bigbox store. It's the only species in it's family. It's a common furniture wood in North America and I don't know if it grows anywhere else.

: Check this out- a 5,000 year old door found in Schweizerland and
: it's made of Poplar. I thought you guys said that stuff wasn't
: rot resistant! It lasted 5,000 years longer than what I ever
: expected!

:
: http://edition.cnn.com/2010/WORLD/europe/10/22/switzerland.ancient.door/index.html