Birke f (genitive Birke, plural Birken)
From Old High German birka, bircha, from Proto-Germanic *birkijǭ, from Proto-Indo-European *bʰerHǵs. The Old High German variant birihha would have led to modern *Birche (compare Kirche). Cognate to Dutch berk, Low German Bark, English birch, and Swedish björk.