It's a traditional drink in areas with birch forests. Just like you would probably not hear anyone talking about consuming sumac tea if you had been living in New York for 10+ years, you would probably need to be more deeply integrated with the older indigenous culture to hear about it.
That's what strange to me, I'm friends with a Sámi, family are herders of reindeer in the north, visited them a few times and never heard of birch water.
That's interesting. I think the Sami tap birch trees, but don't know for sure. I know it's still done in Finland and Russia, but it might not be an important part of Sami culture.
