Old Norse bjǫrk

← Proto-Germanic *berkō (inherited)

→ Danish birk (inherited)

→ Faroese bjørk (derived)

→ Westrobothnian bjerk (inherited)

→ Icelandic björk (derived)

→ Norwegian Bokmål bjørk (derived)

→ Norwegian Bokmål bjerk (inherited)

→ Norwegian Nynorsk bjørk (derived)

→ Old Norse birkja (link)

→ Old Norse birki- (mention)

→ Swedish björk (derived)