I think "julgransplundring" is a Swedish tradition. If not please tell. However, "Julgransplundring" is a party when the christmas tree is stripped from all decorations (!).
According to tradition, this festival takes place 20 days after Christmas. The background to this is well that there was hardly any pine needles left and the Swedes are taking every opportunity for a party.
Do you think this sounds interesting then you are cordially invited to the Swedish julgransplundring on Wednesday 13 January!