What does it mean?
If you have lived in Norway for a while, you’re probably familiar with the concept of bærtur, or berry picking, a popular activity that involves strapping on plastic boots and hitting the forests to look for berries.
But the expression helt på bærtur has little to do with the actual bærtur. Helt på bærtur is used to describe someone who does not know what they’re talking about or is lost (either literally or in a conversation).
For instance, if I say that Erna Solberg is the President of Norway you might exclaim: Er du helt på bærtur, eller? ('have you completely lost it?'), given that Solberg is not President, but Prime Minister.
Or let’s say we’re on a real bærtur, actually out picking berries in the forest, and I’ve read the map wrong for a good hour, meaning the closest T-bane (metro station) is now really far away, you could say herregud, vi er helt på bærtur, jo – ('oh my goodness, we’re really far off').
Avoid using it like this
I would advise you to avoid using it twice in the same sentence, like ABC news does here:
Randi var på bærtur og fant en drone som var helt på bærtur: 'While berry picking, Randi found a drone that was completely lost'.
It's not a great combination: most Norwegians would use the expression just once. Otherwise it would be smør på flesk, another great Norwegian expression that we'll deal with next time.
But if you did use it twice, I could say nå synes jeg er du på en språklig bærtur her: 'I think you're pretty off language-wise here, buddy'.