This inscription was most probably meant to have the same message as N 364 (which you'll also find in Borgund stave church) : 'tistill', mistletoe and - the third - thistle. A magical rhyme ? It also appear here : Ög 181, N A39, Vg Fv1992;170.
My friend Ogneslav visited Borgund stave church, and he sent me the photo. Thanks !